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PRESENTED BY

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PQBLISHED BY THE

NEW SERIES.

Vol. III.

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HARTFORD, CONN,
1882.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY,
New Series— Vol. III. HARTFORD, CONN., JANUARY, 1882. No. 1.

Destructive Explosion of a Battery of Boilers.*

A few minutes before 5 o'clock on Sunday morning, Nov. lo, 1881, ten boilers ex-
]iloded at the Salt and Lumber Manufactory of Hamilton, McClure S: Co., situated on
the Saginaw River in the town of Zilwaukce, jNIich.

Four men who were on duty in tlie tire-room at the time were instantly killed, and
property variously estimated from !j;30,000 to $25,000 damaged or destroyed.

Fii;. 1.

The ten boilers were of the liorizonfal tubular pattern, in a one-story boiler-liouse,
apart from the other buildings. No. 1 boiler was set singly, next to tlint a batttn-y of
four, Nos. 2, '3, 4, and 5; a second battery contained five, Nos. 6, 7, 8, !», and 10; each bat-
tery having but one furnace for all, witli suitable fire doors for each boiler. Each of
these Ijoilers were 50 inclu-s in diameter l)y 21 feet long, of ^\r iron originally, but since
considerably thinned in places, single riveted. The single boiler was 50 inches in di-
ameter by 13 feet long — j^. iron.

These boilers were arranged to feed in each battery through a 2^ inch feed-pipe, which
delivered its water into two 16-inch heaters, set in the up])er part of the back connec-
tion, extending transversely across the boilers, and sui)ported at tlu; ends by the out-
side walls of each battery. From the 1 eaters, the feed passed into the nuid-drum, situ-
ated beneath the boilers in the usual way, and connected to Ihem by ample-sized
nozzles.

^Thc above report wan prepared by Mr. P. B. Allen, Bpccial agent of Llie N. Y. Dupartnicnt of tliif Co.

8605

THE LOCOMOTIVE.

[January

"When uiuliM- steam, the feed-water after its jiassage thrniiyh the heaters and niurl-
ilruiu, entered the boilers at a liigh temperature. Botli an injcictor and pump were used
for the purpose, and the feed supply seemed abundant. Above the boilers there was a
steam-drum with trn-incli nozzles connecting each l>oiler of the battery; on this drum
there was one common lever safety-valve. See Figs. 1 and 2.

The boilers were run day and night under a steam pressure of fiom 50 to 110 lbs. ;
at night they were under the charge of a head tireman, with instructions to call the en-
gineer who lived conveniently by, if his presence was needed. He was believed to be a
very trustworthy man, of whom his employers and associates spoke in the highest terms.
There was a steam-gauge, also a water-gauge glass on each battery ; the intermediate
boilers had one gauge-cock which seemed to have been from one inch below, to three
inches above the tubes on different boilers. It did not appear to me the fireman could
rely on the gauge-cocks, but would depend on the glass water-gauge ; an excellent auxil-
iary in the hands of a ca])able engineer, who verifies its indications by trying the cocks.
It may be a source of danger to others if too implicity relied upon.

.<&.

(D^

Fig 2.

A majority of these boilers were originally of the two-flue variety, with 30-inch
domes. Tlie flues were cut out and tubes put in some years ago by former owners.
Present owners had some additional tubes put in certain boilers, and supposed all were
put in thorough repair at that time, some 18 mouths before the explosion. With per-
hai>s two exceptions, these boilers were 15 or 16 years old, covered by numerous patches,
thinned down in spots by corrosion, and badly crystallized as shown by the granular
edges of the ruptured plate.

I was informed l)y the management there was a standing order, that all boilers should
be thoroughly cleaned out once a month. Besides that, they were tilled up and blown down
(part way) under pressure several times every Sunday. The river water used for feeding
the boilers was very muddy and formed a troublesome deposit of sediment on the shells
and tubes, if these precautions were not observed. The addition of the upper row of
tubes considerably lessened the steam room, thereby increasing the danger from foaming,
while the neglect to change the gauge-cocks, in all cases to conform to the altered tube
level, made their indications deceptive as in Fig. 3 — and the use of such boilers attended
with great danger.

1882.]

THE LOCOMOTIVE.

With our prescDt knowledoe of boiler construction, sheets of A inch iron, siusle
riveted for a boiler 50 inches in diameter with the iwessure required, and for the service
intended, would be considered rather light. The sliells, too, were dangerously cut away
in jiutting in the man-hole mouthpieces, the longitudinal openings of which were IS
inches across the grain, instead of girthwise. Among the wrecked fragments of tlie
seven badly shattered boilers, I coimted several that ruptured through the line of the
weak man-hole opening. After tlie lapse of so many years, witli the usage to which tliese
boilers had been sul)jected, we may prudently assume that the tensile strength of the
iron did not exceed 42,000 lbs., and I believe it would have been considerably less tlian
that, remembering that parts of the shell had been reduced by corrosion, and oilier

Fio. 3.

causes incidental to their use, so that it callipered Ijut ^ inch. We have approximately
42000 X. 25 420 _

25 ~~fj '^^ ^^^- steam as their safe working pressure, while the actual work-
ing pressure as testified l)y the engineer before the "Coroner's Inquest" was, "They car-
ried from 40 to 80 lbs. steam during the season, and sometimes wjieu the mill shut down
it would run up to 90 lbs. before it could be controlled."

With the exception of No. 1 boiler, these boilers were suspended by a 1^ incli
hanger bolted to a cross-beam al)Ove in the usual way, and also by stands under tin;
shell at the front and back ends. See Fig. 2. It is not known what conditioii those
su])ports were in, nor whether (lie load was properly distribuled; the enormous weight
of the boilers, steam-drum, pi'i)e attachments and liltings, brick covering, mud-drums.

THE LOCOMOTIVE. [January,

etc., with the c'ontiiinud water, must in the aiiHTegate have exeeedeil 52 tons in the bat-
tery of four boilers, Fig. 1, and would, if not properly distributed, have seriously endan-
gered their safety. Many explosions of hite years have been attributed to that cause.
All the suspended weight on the cross-beam was sustained by the two side walls, the
condition of whieli could not be determined at the time of my visit, after the wreck had
been cleared up, and the work of rebuilding commenced.

There were three safety valves for the ten boilers; No. 1 had a separate valve on
top of steam dome, with a free escape into fire-i'oom. The battery composed of Nos. 2,
3, 4, and 5, had one 7-inch valve on top of steam-drum ; the escape from this valve
was through a 8^ inch jiijx to the Salt lilock. Figs. 1 and 2.

According to the regulation of the U. S. Steamboat Inspection Service, which bases
the safety-valve area upon the heating surface of the boiler, this, though not alisolutely
correct, is witli the data available to an inspector, a very handy method for obtaining
approximately the required area. Assuming two-thirds of the shell and three-fourths of the
tubes as effective heating surface, gives 072.20 Sfj. ft. in each boiler, using the rule (juotcd

H. S. , 972.29

— ^.^ - we have — — 38.88 .so. in. area, or about 7 inches diameter of safety valve.

25 2o ' -^

How nearly they complied with this rule will be apparent in tlic fact as demonstrate<l,
that the battery of four boilers were dependent on a safety-valve, having an outlet of but
9.62 sij. in. It may be doultted, however, if the use of a 7-incli safety-valve would have
been advisable in this case, particularly in view of the limited steam space and tendency
to foam. Good authorities favor the application of two smalh'r valves to obtain tlie
requisite area as affording greater security than one \al\e of Luge diameter. (Loc, New
Series, vol. 1, p. 131, 148.) The other battery of five boilers, Nos. 0, 7, 8, 9, and 10 had a 6
inch safety-valve foi- all, connected to the steam-drum, same as the battery shown in Fig. 1,
Init it was better connected, the escape pipe to the salt block being the same size. It
was the custom, I was informed, to have two Aveights on safety-valve lever during the
day, one of which xhould Itarc lieen rfrnorcd at night and the remaining weiglita shifted in,
so as to l>low off at about 40 lbs. The fireman had been detected in moving out the
weights during the night, so they might accumulate jjressure, while the fires were at
their best. The watchman saw 65 lbs. on the steam-gauge an iiour before the explosion,
which would indicate they were violating orders, when th^ met their deaths. The fuel
used, wood slabs, when dry, makes an intense heat; the habit of the fireman is to fill up
the furnaces from grate to boiler bottom, and rest as long as possible between times.
Tlie watchman on his last visit to the fire-room, but ten minutes before the explosion,
noticed the men at their work; he engaged in conversation with them; everything so
far as he could see and judge from their actions was about as usual; they had just put
in their last fire, and as he expressed it, "It was a big one."

The immediate cause of explosion, and point of inital rupture, I find myself unable
to decide. It may have been due, I think, to any one of several causers which I find ex-
isted, and from which these boilers were liable to explode at any moment, or possibly a
combination of these several jii'cdisposing causes, namely : —

1. Weakness of the boilers. Primarily that of construction, 1)ut increased by long-
service under the unfavorable conditions of high pressure, bad water, and lack of skillful
sui)ervision.

2. Insufficient number and arrangement of safety-valves, to permit the free dis-
charge of steam generated in the boilers, which, should the steam outlets be suddenly
closed, would permit a dangerous accumulation of pressure until explosion occurred,
which pressure, in all probability, would not greatly have exceeded the working pressure.

3. Danger from over-heating and rupture of the exposed shell along fire line, owing
to the false position of the gauge-cocks.

1882.] THE LOCOMOTIVE. 5

4. Danger from foaming, through hick of necessary steam space, consequent ujjon
the addition of the top row of tubes. This danger was further increased by the una-
voidable use of muddy feed-water.

5. Possibility that the Itoilers might have been strained on the girth and horizon-
tal seams, by the shifting of the supports (assuming they were properly placed at first)
and uneipial distribution of the load, in whicli case they (boilers) might break in two.
This would be most likely to occur when they were pumped up to an unusual height, as
they are believed to have been on the morning of the explosion, preparatory to blowing-
down wheu the engineer came on duty.

Could I have reached the scene of the disaster immediately after the explosion, or
even before the wreck had been cleared up, important corroborative evidence might
have been ol)tained, that would have assisted in solving the problem.

I tliink the explosion occurred in the battery of four boilers (Fig. 1), for the destruc-
tion was the most complete there ; absence of water and red-hot boilers was the cause
assigned by the "coroner's inquest," but unprejudiced men, if they have experience in
such matters, will look long and, if I mistake not, fruitlessly for indications of low water
in this explosion. One of the gentlemen who testified at the inquest and attributed low
water as the cause, when re<juested to point to some evidence of it very frankly said
his only reason for thinking low water the cause was because he had always heard tiiat
given as the cause of explosion, and knew of no other. A casual inspection of the arrange-
ment of heaters and mud-drums will show that when the boilers were fired up, as they
were at the time, it would be im])Ossible to feed cold water, for the feed would have to
traverse two heaters, each about 20 ft. long, and thence into the mud-drum, before it en-
tered the boilers at a temperature nearly as high as the steam.

That ten boilers should have exploded simultaneously seemed an unfathomable
mystery. Kcally Ijut nine exploded, for No. 10 boiler was only thrown out by the force
of tile exi)losion. We do not know that nine boilers exploded simultaneously, for it was
testified before the inquest by one of the workmen that two detonations occurred in
rapid succession. In that case the second explosion would be due to the concussive jar
of the first. The setting of these boilers and size of the steam and water connections
made each hatfcnj practicaUij one hoihr with an enormous destructive energy in the event
of explosion.

In conclusion, I attribute the violence of this explosion to the liberation at time of
rupture of the mechanical energy of a large mass of water at a liigh [)ressure, and its
instantaneous vaporization at atinosplicric pressure.

Inspectors' Reports.

NoVK.MHKK, 1881.

The absence of returns from some of the larger offices ]irevents our givin<>- the com-
plete summary for the month of Novemlicr. Tlie returns as far as received show 1,394
visits of inspection, and 2,823 boilers examined, 1,217 of which were internal inspections,
and 348 others were subjected to hydrostatic pressure.

The number of defects found so far as rei)orted foots up 1,470, of whicli number
352 were regarded as dangerous, as per the following detailed summary :

THE LOCOMOTIVE,

[January,

Furnaces out of sliuix-,
Fractures,
Burned plates, -
Blistered plates,
Cases of dcpdsit of sediment,
Cases of incrustation and scale,
Cases of external corrosion.
Cases of internal corrosion,
Cases of intenia! yi'oo\ini>',
Water-gauii'cs defect i ve.
Blow-out defective,
Safety-valves ovei-hnided,
Pressure-gaui>cs defective,
Boilers without gauges.
Cases of deficiency of water, -
BrokcMi 1)races and stays.
Necks leaking.
Seams leaking,

Whole

number.

Dangerous.

103

17G

101

171

218

812

101

1,479

The instructions to l)oiler attendants issued by the Manchester Steam Cxeris' Associ-
tioii, after giving directions what to do in cases of low water, closes with the following
sensible words: " The best advice the Manchester Steam Users' Association can give to
boiler attendants with regard to shortness of water is, — do not let it occur. Keep a
sharp lookout on the water-gauge."

Tlie above is tiu; only sure way that has yet been discovered to guard against low water.
There have undoubtedly been many excellent devices invented and put to use, to give
warning to the attendant when the water gets dangerously low, ))ut none of them are
inrallil)]e. The tendency is to rely too much upon them, and under such circumstances,
when they do become imperative, they are worse than useless ; they become a very dan-
gerous thing. This is especially apt to be the case where the water is not of the very
best (juality, and the apparatus cf)nsists of anything of the nature of a whistle, connected
to the boiler with small pipe connections. Such apparatus is almost sure to be neg-
lected, so that the pipes become filled with sediment or scale, and tiien low water is tol-
erably certain to l)e the result. We could mention a case now, Avhich occiured within a
few miles of here not long ago, where implicit reliance was placed upon a contrivance of
this sort, and witli the lirem;in in constant attendance the water got low, and the first
indications of it that were noticed were the buckling of the plates of the shell and the
tube-sheets, whereby the seajns were started, allowing the steam and water to escape.
When this occurred the fireman became frightened and incontinently fled, no doubt
ex))eeting every inst;int to have his fii^ht accelerated l)y the explosion of the l)oiler.
Fortunately this did not occiu', ;is the boiler was well nia<1e, of excelhait material, and
hung together, to use a. homely )ihr;ise, until the w.iter had all escaped, but of course the
boiler was totally ruined.

The common glass gauge is also a very dangerous thing in the hands of a fireman or
engineer who neglects to blow it out tlioroughly every three or four hours at least.
(And it will not do to merely open the blow-off cock for a few moments. The proper
way to blow out the glass water-gauge is as follows: shut the iqipcr or steam valve
first, then blow through the lower valve until everyt iiing is free and the water comeHoat clear;
then shut the hurcc valve and blow through the upper one in tlie same manner. If the

1882.] THE LOCOMOTIVE. 7

valves are not closed and lilown separately, it is impossible sometimes to tell whether
one of them may not be tightly stopped up. After the blowing out is done ie sure you
open lK>t7i valves again.)

We have had many cases in our own experience, wliere such neglect has produced very
serious conseiiuences. This will l)ecome very apparent, when we state that the chemical
analyses of samples of water sent to us from different localities, show that the amount of
insoluble matter contained in the feed water, is in some cases as great as 155 parts, by
weight, in 100.000 parts of water, or nearly 91 grains per gallon of water. Suppose,
then, that we have a boiler evaporating, as many do, 25,000 pounds of water daily ; if
none of the sediment is blown off, there will be nearly 39 pounds daihj deposited in the
boiler. Witli such an amount of sediment in an ordinary sixty-inch boiler, it will re-
quire very little argument to convince any one of the absolute necessity of paying the
closest attention to all ]npe connections ui)on which in any way depends the quantity of
water in the boiler.

There is a vast difference between firemen in the matter of keeping things about the
boilers in good order. Some take especial pride in keeping their gauge-cocks always
clean both externally and, what is of far more importance, internally. Others don't seem
to care whether they are plugged up or not; in fact rather seem to prefer the latter state
of things, for then they know that it is of no sort of use to ever try them, and thus they
are saved the trouble of doing so.

But they are not fdirays to lilame. In many cases we are accjuainted witii, gauge-
cocks are so comnletelv worn out with long and faithful service, that they leak upon the
slightest provocation ; and the mere matter of trying the height of the water involves so
much work in trying to stop the leaking of the cocks afterwards, that the fireman hates,
and justly too, to go through the operation. In addition to this, gauges which leak,
and thus have constantly a current of water flowing through them, are much more liable
to get choked up. Leaky gauges sliould always be attended to at once.

We have thus alluded to the item of deficiency of water at some length, because it is
always not only dangerous in the extreme, but a very costly one generally, to the owner
of the boiler when it occurs.

BOILER EXPLOSIONS.

December, 1881.

Oil Works (150). — A boiler in the Yazoo Oil Works exploded Dec. 1st, witli terrific
force, tearing away the boiler-house and end of the main building. Seven colored men
■were wounded, four fatally. The boiler was an old one, with five tines, 40 inches in
diameter, 30 feet long, and was blown across the street under a house ojiposite, tearing
away the support to the house.

CoAi, Mink ( 151 i. — A boiler exploded at midnight, Dec. 1st. in the Wadswortli Coal
Company's mine, near Doylestown, Wayne county, Ohio. John Steinlein was fatally
injured, and another man was seriously lun-t. The exphjsion oecuned in the mine, and
the wounded men crawled half a mile to get to the siuface.

Soap Works (152). — The boiler of tlie Mission Soap and Candle Works, Sixteenth,
between Folsom and Harrison streets, San Francisco, Cal., l)lew up about four o'clock in
the morning of Dec. 7th. The niglit wat(;hman and engineer were the only persons on
the premises at the time, and escaped unluirt. The building was demolished. A S(piat-
ter shanty and Chinese wash-house adjoining were slightly damaged. The building,
worth $3,000, is a total loss. Machinery, valued at $50,000, is more or less damaged.
The boiler was high pressure, 18 feet long and two feet in diameter. A piece weighing

8 THE LOCOMOTIVE. [January,

a tdn was tlu-owii o\ cr a two-story l)uikliny, landing- in a i; ravel pit a thousand yards
distant. Other iie.-ivy pieces were l)h)wn throiigli tiie walls of tlie warehouse, shattering
the adjoining l)uildings, and bricks, timber, grease, and candles were distributed over
the neighborhood. That no lives were lost is almost miraculous.

Cotton (iIN (153). — A terrible boiler explosion occurred at .Jones's gin house, near
Elberlon, (Ja., atone o'clock, Dec. 8th. Clill'ord, the eight-year-old son of W. B. Jones,
had his head blown off; Joseph, a four-year-old son of the same man, was badly cut
about the head; ITarve}' Morrison, colored, had Ixitli liis legs and one arm broken and
will die, and another negro was severely hurt.

R()M.iN(i Mil, I, (l-')4). — ^Dec. 0th, about five o'clock r. M., a boiler burst in the Key-
.stone Rolling Mill, in the fourteenth ward, Pittsburgh, Pa., completely demolishing the
boiler-house, scattering the debris in every direction, and killing one man and seriously
injuring ten more. At the hour nuiitioned jx'ople living in that portion of the city were
startled |jy a terrille explosion, and hurrying to the mill found on evei'y side evidence of
a terrible disaster. As soon as tin; debris could be cleared away the work of hunting for
bodies began. Fortunately, however, this resulted in tiiubngthat but oue man had been
kille<l. He was the (ireman, John Quinn, and was in the boiler-house when the explosion
occurred. He was badly scalded, but death resulted from concu.ssjon of the brain. Of
those injured only one, Albert Gideon, it is tlioughl will die. Tie is seriously Ijurned,
besides having a com]iound fracture of the right ankle. Upon investigation it was found
that one boiler of the battery of tive had exploded. The engineer, Charles Bennett, had
gone into the engine-room a few minutes before, and thus escaped injury. lie says he
was carrying 100 pounds of steam, and that tlie boilers were inspected three months ago,
when ])ermission was given to carry 120 ])Ounds. The names of those injured and the
natur(! of their injuries are as follows: John Pi-ice, a ])uddler, injured on the head and
side; Andrew Dugolds, a coal-cart driver, struck on the h(;ad l>y a Hying piece: George
Rolnnson, bricklayer, cut about the legs; John Thomas and Thomas Thompson, cut
about th(! head and back; .John Brislin a, heater, scalded; .lohn .Jones and Evan Thomas,
slightly injured about head and legs.

Pi..\NiN(i Mill (IT),')). — The boiler in Jjoomis's planing-mill, at Sparta Center, Mich.^
exploded on Dec. 13th. Cause, low water.

S.\w Mux (l.'je). — The boiler in T. .J. Sheridan's ifflll, at Solon Center, Mich.,
exploded at noon, Dec. l.^>tli, killing thi' engineei' and (•f)mph'tely demolishing the mill.
The loss is estimated at $7,000.

]\JiNE (157). — A boiler at the Diamond miiu-s of Charles Parish tt Co., Wilkesbarre,
Pa., exploded Dec. 20th, and demolisiied the engine and boiler houses. J^oss, $6,000.

Fi.oniUNG Mri.L (158). — Tlic boiler of Taylor's Manhattan Mills, located at North
Toledo, Ohio, exploded at 3.30 o'clock, Dec. 21st., demolishing the engine-house, damag-
ing the mill badly, and instanlly killing the engineer, I^ouis J. Monnat. The latter was
standing at the throttle at the time, and his body was blown into fragments and scattered
over the yard. Tie was about twenty-three years of age, and married. The damage to
the building and machinery is estimated at f8,000, on which there was a casualty insur-
ance of $3,000.

POTTRUV (150). — The l)oilcr in Kisley's pottery, Norwich, Coim., exploded Dec. 24th.
George L. Risley, pro])rietor, was terribly scalded and has since ilied.

Mii,[, (UiO). — AVatson's mill, at Gurdon, Ark., was blown up Dec. 2Glh. The

casualties were: Charles Keel killed and Cool French fatally wounded. Allan Creile,
R. J. Sappington, and L. McFarland were seriously injured. The mill is a total loss.

Cloth Mill (IGl). One of the boilers in the slmde cloth factory, owned by Irwin tt

1882.]

THE LOCOMOTIVE

Slean, Oswego, N. Y., exploded Dec. 27th. The middh' of tiie building was demolished.
Captain William Dorman, fireman and night watchman, is missing. Loss $15,000.

Saw-Mill (102). — Theboiler in the saw-mill near Winaniac, Ind., cxi>lodedDec. 31st,
killing John Helm, fatally injuring Daniel Drit, and severely injuring a tliird man.

Accidents otheh than Boiler Explosions.

The steamer Paris C. Broicn bound from New Orleans to Cincinnati, burst her steam-
pipe, Dec. 26th, near Catfish Bend, scalding 12 of the crew, throe seriously. Tliree negro
roustabouts jumped overboard and have not been seen since.

During the temporary absence of the engineer, Dec. 12th, tlic ])iston-rod of the
Harris-Corliss engine at the rubl)er works, Woonsocket, R. I., broke at tlie cross-head,
causing the cylinder-head to l>low out with great force, and doing considerable injury to
machinery. The damage is estimated at $1,200.

Classified List of Boiler Explosions for the Year 1881.

Sawin«r. planing, and wood-workinir mills,

Portable!', hoislers, thrcfherrr, pile-drivers, and cotlou-Kins,

IroQ works, rolling-mills, fnrnaces, foundries, machine it boil'rsirps.

Steamboats, st"m titfjs, yachts, st'm barges, dredges, and dry-docks.

Locomotives, -

Paper, flouring, pnlp and grist mills, and elevators.

Distilleries, breweries, malt and sugar houses, soap and chem, w'ks.
Bleaching, dyeing, digesting and print works, slauglitering, etc..
Steam heating, drying, dwellings, schools, stores, pub. holdings, etc.,
.Mines, oil wells, and refineries, --------

Cfitton and woolen mills, and textile works,

Tannery.

Miseellaneone Works and mills not designated,

Total per month,

1-5 , fo

1
1
O

0 0
•i I 4

!2 l(i

a. 03

8 115

8 s

14 16

l(i

Summary of Boiler E.vplosions and Persons Killed and In.iuked in the Year 1881.

O
o

"3
o

«5

3(1

Explosions,

1.59

Number of persons killed, - . - - . -

f'l

251

Number ol' persons injured,

3.'-)

I'.l

lit

313

Explosions Nos. 5, 11, and 41, in the monthly lists, were repeated through our informant's mistakes in locating
them in ditTerent places. Consecpieiitly the total number of explosions is 159, as above, instead of 162, as
shown by the monthly enumeration.

We understand that there is considerable doubt in tlie minds of many that the cuts
of defective rivets shown in our last issue rf'prcscnt ''real rivets." We will only say in
reply that tlie cuts in f|ue.stion were made, as acctu-ately its possible, from full-sized ])hoto-
graphs of rivets which will be cheerfully shovvn to any "doubting Thomas" who will
take the trouble to call at this oflice. *

10 THE LOCOMOTIVE. [jANtJARt,

Mht •tttmttt

HARTFORD, JANUARY, 1882.

Witli this issue commences the tliird volume of the New Series of The Locomotive.
Tlie favonible reception it h:is met with from engineers and its mechanical readers
iicnerally, leads us to believe it to be of some value as a means of disseminating infor-
in;itiiin gained l)y the com|)any's experience concerning boiler explosions .'ind the safe
and economical use of steam, and justifies >is in endeaxoring to make it as valuable in
tiie future as it has been in the past.

]n another column will be I'oiuid a classilied list, as well also as a summary of all
the steam boiler explosions occurring in the United States which hiive come under our
notice during the past twelve months. While some of the minor and more uiumportant
ones may have been overlooked, or have not been reported to us, we aic conti<lent that
we have secured records of nearly all that have occurred.

A study of the classification of the exploded l)oilers may possilily be of some
interest to our readers. By n'ferencc to this list it will lie seen thai the u.sual high |ier-
centage of explosions occurred in saw-mills and other wood-working establishments —
nearly one-foiu'th of the whole munber being in this class. Doubtless the greater
number of those reported simi)ly as "mills" would prove, on further inquiry, to be in
saw-mills or some allied industry. The (Question naturally arises: What causes so many
destructive explosions in saw-mills and wood-working establishments? While we can-
not wholly agree with the opinion expressed by some scientitic journals that the greater
number of them are caused by the use of light fuels, such as shavings, saw-dust, etc., we
will admit that the fre(|uent opening of tiie fire-doors, which is rendered necessary by
the use of such fuels, tends to deteriorate the boiler and .shorten its life. It would
proljably be found, if ;dl the facts could always be obtained, that the fre(pient explosions
among this class of boilers are mainly due to the carelessness and ignorance of those in
charge of them. It may fairly be assumed that very few of them are ever inspected by
any one who is competent to discover fnults and correct abuses in their management.
Thcv are neglected, safety-valves arc allowed to corrod<rand stick fast, and they are
nearly always run at higher pressures than would be considered safe by careful engineers.
The violence whi(;h is characteristic of this class of ex])losions is good evidence that
high pressures generally have something to do with them.

The next in order of frequency are ])ortable engines, mainly those used for agricul-
tural ])urposes; which class of boilers are generally under the same unfavoraljle condi-
tions of use and management as the majority of saw-mill boilers, aud the ])roportion of
those blown up to those in use is probably fully as high as that which obtains in the
former case.

The other classes of ))oilers show about the average number of explosions. One
thing we would ])articularly call attention to is the very small comparative number of
explosions which occur in textile manufactories. Among the thousands of them in use
in this coimtry, we have but four explosions to chronicle for the past y(^ar. ^J'liis, we
think, is strong corroborative evidence of the correctness of the oj)iiuon advanced by this
company, that good care and management, combined with unceasing vigilance, will
prevent most of these destructive .accidents. This class of boilers, although |)r()bably
no better constructed than other kinds, rarely explode. The only i-eason that can be
assigned for this is, tliat they are in most cases under the direct supervision of a more
comi)ctent and trust worthy set of engineers and tii-emcn than any other class, and the
beneficial results are at once a})])arent in their comparative immunity from e.\[)losion.

1882.]

THE LOCOiyiOTIVE

Drifting- — Its Effect upon Boiler Plate.

COMPARATIVE RESULTS WITH STEEL AND TKON PLATES.

By James E. Howard.

[Written for the Boston Journal ol' Commerce.]

The peculiar value of a niatcrial for boiler construction deijends upon its fitness to
resist those strains whicli are likely to come upon it when it is in the boiler. A metal
possessed of high tensile strength, or in other words, whicli has the greater strength for a
direct pull, is not always the best for a boiler. Indeed, it may be 'luite the contrary, a
very unreliable and unsafe material for this purpose. There is no positive injury in having
a high tensile strength per se, but this cjuality is not generally accompanied by those
others which the necessities of the case demand. When a suitable material has been
selected, it should not be subjected to any treatment known to be injurious. It is, how-
ever, a strong argument in favor of that metal which permits certain maltreatment, juost
commonly to be guardeil against, with tiie least comparative injury, a metal having good

<|ualiti<'s in reserve tliat are not snppDsed to be called oiit, ]nd wliich, nevertheless, may
be. Drifting has been very [)roperIy condemned, yet, after all that has been said upon
the .subject, it is doubtful whether the practice will soon be abolished altogether. This
fact should be borne in mind when selecting boiler plate.

The results here presented are from some recent English experiments, made l)y
Thomas W. Traill, engineer surveyor-in-cliief ; alsd, from some experiments by the com-
missioners of admiralty. In addition to showing the com})arative behavior of steel and
irftn plate, we may observe these tests furnish a very satisfactory indication of the duc-
tility of the metal, and in the absence of a testing machine a few siin])le tests like these
will ])rove of great value.

The first series of tests were carried oiil at (he works of the Steel Company of Scot-
land, where the steel plates were maiuifactured. The wrought-iron plates were of good
fpiality, the maimfacturer's name not being mentioned. Square plates were used, having
a drilled or punched hole in the middle of each. The drifts employed had a taper of
aVjout .05 in. in one inch, they wer(! turned in a lathe, each was driven from one side of
the plate a .short distance, and then from the other side, enlarging the diameter of the

THE LOCOMOTIVE.

[January,

hole about .08 in. before reversinnj. The drifting was continued till there was complete
fracture of the plates.

For our i)urpose we will compare the results whe-u fractiu'es lii'st api)eared, as it
seems (|uite jirobable that liad tlie plates been under a tensile strain acting on tlie drift
pin, after the manner it acts upon tlie rivets in a joint, instead of simply resisting the
enlargement of the hole, the maximum resistance would have been reached about the
time fractures first appeared. From tlii.- time onward, the resistance of the plates would
graduallj- diminish till the fractures were fully developed.

Tabut.ation ok Cold Dkipting Tests hade at the Works of the Steel Coipany

OF Scotland.

Q i>'a

"" i".

2 = "

rS ♦^ OJ

sm Zi

tfc ^

-2 °-:C

«»-«';:;

Size of
Plate— ins.

Hole — inches.

^ ^ c

DESCRIPTION OP FRACTURE.

■- C3

.Ss:£ 1

.5- 5

'-^

P « 0

Steel

«K'S 6J4

% drilled

2.05

173

Plate tore at hole.

14!)

Steel

6!4.K (i>4

•^ drilled

2.05

173

Plaie cracked at outside edge.

).tO

Steel

ejix V,]4

V*i

•^ puDchod

201

168

Plate cracked at outside edj^e.

151

Steel

6K»x UK'

■14 piinclied

1.87

1.50

Plate cracked at outside edge.

L-J-J

Steel

6>^x 6^

j -M pmichcd. then drill-
) ed to 1 in. ilia.

1.65

Plate cracked at two outside
edges.

153

Steel

6,4x 6)4

% l)unched, then drill-
ed t" 1 in .

2.70

170

Plate cracked at outside edge
and at hole.

153«

Steel

10 xlO

% drilled

2.80

273

Plate cracked at ontside edge.

153A

Steel

10 X 9?i

i<i

3^ piinclii'd

2.50

233

Plate cracked at hole and edge.

ihi

Iron

fii/,s 6U,

V6,

?i drilled

1..30

Fracture beg:in at outer edge.

155

Iron

eUx 6Ui

% punclie.l

1..36

Fracture began at outer edge.

156

Iron

6!4x 614

1 -Ji punched, then drilled
\ to 1 in.

1..39

Plate cracked suddenly from
edge to hole.

157

Iron

6i4x OK.

•Hi

Ya drilled
% punched

1 13

Fracture began at outside edire.

158

Iron

«,Uix 6>4

1.20

Fractureil at hole and at edge.

159

Iron

6>ixG>^

I % punched, then drilled
1 to 1 in.

1..3(1

Fractured at hole and at edge.

An examination of the above table shows very little difference in the behavior of
the plates, whether the holes wore drilled or punched.

In the steel plates the elongation of the drillcil holes was 173 per cent., wliile for the
punched holes the elongation averaged 159 jier cent. W^hould not be misled by this,
however, to as.sume that, practicallj', it doesn't matter whether the holes are drilled or
punched. A great many tests have demonstrated the superiority of joints made with
drilled holes. Fractures occurred with both punched plates at the outside edges of the
plates, in the same manner as one of tlic drilled specimens failed, which would appear
to indicate that the size of the plates was not sutticient to develop the ditference between
drilling and punching. Tlie same remarks would ahso apply to the iron plates, although
there is a slight apparent advantage in fiivor of the punched holes.

The plates with inch holes failed when about the same enlarged diameters had
been reached as with ^-in. holes, the percentage of elongation being less correspondingly,
again showing the pl.ates failed at the outside edges first, or else simultaneous with frac-
ture at the holes. As between tlie steel and tlie iron, a most suri)rising ililTerence is
found to exist. The iion plate elongated only 73 per cent, where the .steel elongated 173
per cent., or, comparing the areas of the enlarged holes, there was a displacement of .88
S(piare inch of metal in the one case, and 2.8G sijuare inches of metal in the other, more
than three times the displacement of steel than of iron. The ])receding sketch shows
the relative sizes of the enlarged holes in iron and steel plates.

The Inside full circle represents the original hole, the first dotted circle the enlarged
hole in iron plate, the second dotted circle the enlarged hole in steel plate, each meas-
ured when fracture began. The superiority of the steel is here well illustrated. We

1882.]

THE LOCOilOTIYE

should have coufldtnce that if the drift-pin was used upon this metal its effects would
be far less serious than upon iron plate. A distinguished steel-maker of this country
remarks: "It is a fact that good steel will iMulure more pounding than any iron."

The preceding experiments were made upon boiler-plate metal, those following
refer to some cold drifting tests made n]ion steel of higlu'r temj)er.

Experiments upok Cold-dktfting in Steel Plate.

c s
5 ^

Kind of Plate.

201 Crucible steel

a02 Bessemer i^teel

203 Bessemer steel

201 Sub ciirburized steel

205 Whitworth's liquid com-
' prcsse'l steel soft

206 Whitwonh's liquid com-

pressed steel — hard

207 LAtwood's patent steel — soft

208 TAtwood's pat. steel— hard

~ 2

0 V

t— o

^ 0

c =

0 s

(fi

SHxSi4

7-16

m^m

5-16

3>4s3Vi

5-16

7-16

3»4x3ki

7-16

3I4S3I4

7-16

m^m

7-16

W4^m

o s

Hole-
Inches.

S-- »-

% drilled 1.41

5^ drilled 1.39

% drilled 1.39

% drilled 1.73

% drilled i 1.734

5^ drilled
% drilled
% drilled 1

1.39
2.20
1.316

y- -■

E 0 C

a (U y

126

lot;

106

177

106

2.52

115

Description of
the fracture.

Bejran at bole
Began at hole
Began at hole
Began at hole

Began at hole

Began at hole
Began at hole
Began at hole

•SI s

9 ^

.2 1

CJO

76,750
S-2/.60
77,870
65,230

58,970

72.880
5o,680
75,200

.2.S , §5
« o

13.fi 17.5

13.4 19.2
20.3 < 38.3

19.5 1 35.5

31.7

23.1
30.5
21.5

53.2

431
66.9
27.

We see from the above experiments tliat steel having the most ductility, as displayed
in the tensile tests by elongation after fracture and contraction of area, is less injined liy
drifting than the higher grades of steel, tlie most ductile metal having a tensile strength
not far from good wrought iron.

It would have been desirable in councctiDn with tliese exjieriments to have ascer-
tained the etTect of drifting upon tlie tensile strength of the plates. That was not done,
but reserved for subsequent investigation.

We learn with pleasure that the Senate Conunittee on Claims has favorably reported
the bill making an appro|)riation to satisfy the claim of Mr. A. H. Emery of tliis citv,
for the design and construction of the great testing machine now at the AVatertown
Arsenal. An ai)propriation was made to cover tlie estimated cost, but the real co.st,
with attendant expenses to the builder, w-as much greater than the amount apiiropriatecl.
Mr. Emery has received ^31,o00, and lias a claim for $129,000 for disbursements and
expenses. It is the duty of the Goverinnent to recogni/.e and pay for professional work
duly ordered, especially when it is honestly and intelligently performed, and the results
are entirely satisfactory, as Mr. Emery's testing machine certainly is. The bill reported
by the committee appropriates $225,000 as compensation to Mr. Emery for his work. It
will be worth this to the country many times over, if the work of testing materials is
(committed to such a commission as that which began its work by giving ]\rr. Enierv an
order for this great machine. As u.sed at present, it is not likely to be of any great value
to anybody. — Iron Age.

The Philadelphia P/v-w says: " It is alleged by jirominent lawyers of this city that,
for the last til'teen years, not a single jury has been drawn in which all of the twelve were
honest men. Justice has been tliwarted over and over ayain.'' * * *

We can readily believe the above to be true.

14 THE LOCOMOTIVE. [January,

Boiler Explosion under very Remarkable Circumstances.

The mere aniioiincement of a boiler explosion lias, perhai)s. ceased to create auy
interest from the frequency of their occurrence; but the explosion of a 1)oiler which
took place on Saturday last, in the mill of Schumacher & Co., of Akron, Ohio, was of
.so unusual a character as to merit more than a [):issini;- notice. It was in fact a boiler
explosion at a time when there was no steam pi-essure on, no water in, and no fire under
it. The boiler, wliich is the return Hue style, was built at Pittsburgli, and has a shell of
about 72 inches diameter. The plates immediately over the furnace, either from excessive
pressure of steam ;done, oi' aided by the deposit of scale on their interior surface, which
prevented the water from cominy in contact wilii the iron, became considerably bulged
outwards, and it was while the workmen were engaged in cutting out the.sie defective
plates that the accident occurred. They had chip[)ed an opening of several inches at the
forward end of one of the sheets, when suddenly the after end tore apart with a tremen-
dous noise, in fact, so loud was the re])ort that the men engaged in the mill rushed to the
door, exclaiming, " There goes another powder-mill" (one having ex])loded only a few
days before in that vicinity), and it was several minutes before it was discovered that the
rupture of the l)oiler had caused it. One of the men, who was in the act of chipping,
and had his hand hold of the chisel which was wedged in the boiler, was so completely
paraly/ed on one side as to be unable to move, and he was conveyed home very ill. The
rupture took jilace in one of the transverse seams of the l)oiler, tearing the solid iron
between the rivets about one-sixteenth of an inch apart and over one foot in length.
Philosophers and experts in engineering, who have been puzzling themselves and the
public by their various theories of low water and no water, high pressure, super-heated
steam, electricity, galvanic action, unknown and combustible gases, etc., may here lind a
field for further speculation as to the cause of a boiler explosion in which there was
neither steam, fire, nor water.

The above account of an accident which happened in 186G was lately forwarded to
us by Chief Inspector A. C. Getchell, of the Cleveland, Ohio, office. At first we thought it
somewhat resembled the story about the old lady's gun "without lock, stock, or barrel,"
which " went off " and killed some one who was fooling wiUi it and " didn't know it was
loaded," but the letter sent by Ins^iector Getchell explaincTt the matter, and showed that
it was produced by natural causes, the same as all boiler explosions are. It seems that
the boiler had several sheets badly corrugated or buckled on the bottom, which brought
a severe compressive strain on the fines, and consequently an equal tensile strain on the
slicll. The workmen were engaged in cutting out the damaged sheets, and when they
had cut around about a foot, the great tensile strain on the shell, concentrated at the
edges of the cut, tore the shell apart.

The occurrence affords a good illustration of the fact that the strain caused by steam
pressure is not always the greatest that a steam boiler is sometimes subjected to.

It does not appear to be generally known that the value of the mechanical equiva-
lent of heat has within a few years been corrected. It is generally referred to by
mechanical writers as 773 foot pounds. Dr. .loule repeated his famous experiments in
187G, nearly six years ago, with extraordinary precautions, and the mean result of sixty
experiments gave 774.1 foot pounds, witii a ])()ssible error of jj^^, on account of the
" thermoraetric scale error." This value should be used in all calculations relating to
the value of heat as a motive power.

1882.]

THE LOCOMOTIVE.

Proportions for Chimneys.

The following table, which is taken from Robt. Wilson's Boiler and Factory Chimneys,
may be of service to engineers who are in donbt in regard to the efHciency of tiieir ciiini-
neys. It is calculated ou thoroughly sound principles, and may, we think, be relied upon.

>>
£

s of coal burned
lour per squtire
of area at top
himney.

t in inches of
mn of water bal-
d by the draught
sure.

■g s s -i!

0) g a —
c.£ 1 o ^

of top of chim-
in feet per horse
er for 1 or 2

ers.

of top of chim-
in feet per horse \
er for several
ers.

if Hue in feet per
nC power.

5 a> - -o-

" ~ Zl 11

= 0) o o

S <" o 2

Q :>^ o

•So So.

s V. a c a,

£ a ft.Q

£ c ».=

»-.— '

.218

•«5

7S.24

7.3

.146

.091

.183

90.35

.296

8.4

.126

.077

.155

101.01

.364

9.4

.113

.070

.140

110.65

.437

10.3

.103

.064

.129

119.52

11.2

.095

.059

.119

127.77

.58

11.9

.089

.055

.111

135.52

.656

12.6

.084

.052

.105

100

142.85

.729

13.3

.08

.05

.100

125

159.71

.911

14.9

.071

.044

.089

150

174.96

1.09

16.3

.965

.04

.082

175

188.98

1.26

17.6

.060

.038

.075

200

202.03

1.45

18.8

.056

.035

• .07

225

214.28

1.64

20.

.053

.033

.0(H5

250

225.87

1.S2

21.

.05

.031

.063

275

236.90

1.99

22.

.048

.03

.06

300

247.43

2.18

23.

.046

.028

.057

Column 2 shows the amount of coal burned per hour per sipiare foot of Hue-area at top
of chimney, and is calculated by the following formula, W= q^ , in which W = weigbt

of coal burned ])er hour as above; A = area of chimney in sciunre feet; 11= height of
chimney in feet; and .07= a constant.

Column 3 .shows the height in inches of a column of water balanced by the draught
pressure. Apparatus wiiich is necessary to perform this experiment is very simple
and will be described in some future number.

Column 4 is calculated by the formula II. P.=: ,j,rj ;

Column 5 is calculated by the formula A —

Column 6 is calculated by the formula K=^-7-r\ and

Column 7 is calculated by the forinula A= ,. ; in all of wliicii A denotes the area of

•' V I'

flue in square feet, and H denotes the height of the chimney in feet. By means

of the above formula- the pnijiortions of cliimneys for ordinary cases may be very easily

determined.

We would call attention to the article on tlie effect of drifting upon Ijoilcr-plates in
this i.s.sue. More extended experiments U|)on this same sul)jcct are now being made
tmder the aus])ices of this com[)any, the residts of which, when completed, will be ftdly
detailed iu Tue Locomotivk.

THE LOCOMOTIVE.

[January.

Incorporated
1866.

Charter Per-
petual.

Issues Policies of Iiisiirauce after a Careful Iiispectiou of tlie Boilers,

COVEUING ALI. LOSS OH DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

ARISING FROM

•Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.

Full information conrernin;: the plan of the Coin})any'sopfTations can be ol)tainc'(l at the.

CO nivdii^^^isri^'s OFiFiCDB, 'hij^j^tfoieiid, con^isr.

Or at any Agency.

J. M. ALLEN, Prest. W. B. TRANKLIN, Vice-Prest. J. B. PIERCE. Sec'y.

Boai'cl of Dii'ectors:

J. M. ALLEN, President.

LUCIUS J. HENDEE. Prest. ^tna Fire Ins. Co.

FRANK W. CHENEY, Treas. Cheney Brothers Silk

Manufacturintr Co.
CHARLES M. BEACH, or Boacli & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW. Prest. Anier. Nat. Bank.
RICHARD W. H. JAKVIS. Prest. Colt's Fire Arms

Maniil'actnrins: Co.
THOMAS O. ENDEHS, of .Etna Life Ins. Co.
LEV'ERETT BRAINARl), of The Case, Lockwood &

Brainard Co.

Hon. HENRY C. ROBINSON, Attorney at Law.

Gen W. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire
Arms ftlfg. Co.

GEO. CROMPTON, Crompton Loom Works, Wor-
cester.

Hon. THOS. TALBOT. Ex-Governor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manufacturer, Provi-
dence, R. I.

NELSON HoLLlSTER, of Slate Bank, Hartford.

CHAS. T. PARRY, of Baldwin Locomotive Works,
Pliiladelphia.

GENERAL AGENTS. CHIEF INSPECTORS.

THEO. H. BABCOCK,
CORBIN.<: GOODRICH,
LAWFORD .<; M( KIM,
W. S. CHAMBERLIN,
J. L. SMITH,
H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FRIO EM AN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

R. K. McMURRAY,
WM. G. PIKE,
JOSEPH CRAGG,
WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
,1. S. WILSON,
F. S. ALLEN,
J. H. R.\NDALL.
A. C. GETCHELL,
J. S. AVILSON,

OFFICES.

York City. Office, 285 Broadway.

Nkw

PhILADELI'HIA.

Baltimore.
Boston, Mass.
Providence, B. I,
Chicago, III.
St. Louis, Mo.
Hartford.
Bridgeport.
Clkvel.\^nd.
Cincinnati.

430 Walnut St.

10 So. Hollid:iy St.

10 Pcmljerton Sq.

15 Wevl.o.sset St.
1.32 La Salle St.
404 Market St.
218 Main St.
328 Main St.
246 Superior St.

53 West Third St,

0t0tttotite.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series— Vol. III. HARTFORD, CONK, FEBRUARY, 1882.

No. 3.

Explosion at Norwich, Conn.

On Saturday morning Dec. 24, 1881, a small boiler located in the pottery establish-
ment of Mr. Geo. L. Risley, at Norwich, Conn., exploded, demolishing the boiler house,
destroying a considerable amount of manufactured goods, and injuring Mr. Risley, who
was in the boiler room at the time, so severely that he died a few hours afterward.'

Fig. 1.

The exploded boiler was of the upright tubular type, seven feet long, three feet ini
diameter, shell about five-sixteenths of an inch thick, single riveted. It had sixty tubes
two inches in diameter and five feet long, internal furnace alx)ut 30 by 24 inches, and.
was provided with an ordinary lever safety valve, properly connected and in good order.
The boiler was about 15 years old. From the position in which it lay when seen by the
writer, the stamp on the plates could not be seen, but the shell-plates had the appear-
ance of being of good quality, and were sound externally. The appearance of the boiler
indicated that there was plenty of water at the time of the explosion, there being no evi-
dence of overiieating, and this view was borne out by the testimony of one of the em-
ployes, as well as by the character of the explosion.

What, then, caused the disaster ?

The boiler had evidently been neglected, or ratlier the precautions necessary to pro-
tect this type of boiler from injury from corrosion were not understood, the location of
the boiler being low and damp, and from its appearance not in constant use. Under
these conditions special care would be required to protect it from corrosion. Tlie fur-
nace plates were badly corroded, a soft or bolted patch had been put on near the fire-
door, the plates at this point having evidently been eaten through. The upper tube-
sheet and ends of the tubes had suffered severely from the eflfects of corrosion, four
of the tubes having given out, and the holes plugged. The lower tube-sheet, or
crown-sheet, and tubes at the fire-box end of the boiler had sufi"ered most severely,.

THE LOCOMOTIVE.

[Febuuaky,

the tube-sheet being reduced to about one-half of its original thickness, and the tubes
at this end being also badly corroded, so that their holding power was reduced to
such an extent that they were unable to sustain the required working pressure which
was ordinarily about 60 pounds per square inch. The pressure at the time of the explo-
sion probably did not much exceed this amount. When the head and tubes parted, the
lower head bulged downward, and the contained water and steam rushed out through
the holes in the tube-sheet, and the reaction lifted the boiler like a sky-rocket, shooting
it out through and demolishing, the roof of the boiler-house, and throwing it to a height
of 75 or 80 feet at least. It passed completely over a large tree standing near, and came
down about a hundred feet from its original position, falling partly uj^on its side and
burying itself about one-third of its diameter into the ground. The force of the explo-
sion shattered the cast iron base upon which the boiler stood into fragments, and scat-

10]

Jo]

Fig. 2.

tered them in every direction, and blew the unfortunate Mr. Risley who had just entered
the room, violently against the wall, where he was found in a half insensible condition,
severely scalded, and covered with debris.

Boilers of this class cannot be too carefully looked after, more especially when they

are not in constant use and are located in damp places. The furnace plates in particular

-should receive the closest attention, and should be kept clean and often scraped and

painted. Moreover, the shells should always be provided with at least four hand holes

■placed slightly above the crown-sheet, so they may be removed and the interior of the

'boiler examined from time to time, and kejit free from sediment or anything which

would be likely to injure the plates. When no means are provided by which an internal

• examination of a boiler can be made, defects are very apt to arise which the application

of hydrostatic pressure will not reveal, but which are likely to cause the most disastrous

. explosions.

1882.] THE LOCOMOTIVE. 19

Inspectors' Reports.

November, and December, 1881.

Below will be found the complete summary of the work of the Inspectors for the
month of Nov., 1881, which we were unable to obtain before our last issue went to press,
and following it the summary for the month of Dec, and the total for the year 1881.

During the month of Nov., there were made 1,944 visits of inspection, by which
3,924 boilers were examined. Of this number, 1,372 were thoroughly inspected, both ex-
ternally and internally, and 351 were subjected to hydrostatic pressure. 36 boilers were
condemned, being thoroughly worn out and beyond repair.

The number of defects of a serious nature discovered was 1,899, of which number
502 were considered dangerous.

The following table exhibits the defects in detail : —

Nature of defects. Whole number. Dangerous.

Furnaces out of shape, . . . . -

Fractures, - - - - - - -

Burned plates, ......

Blistered plates, ..----

Cases of deposit of sediment, ....

Cases of incrustation and scale, ....

Cases of external corrosion, - - - - -

Cases of internal corrosion, - - - - -

Cases of internal grooving, - - - - ' -

Water-gauges defective, . . . - .

Blow-out defective, --.---
Safety-valves overloaded, - . . - .

Pressure gauges defective, .....

Boilers without gauges, .....

Cases of deficiency of water, . . _ .

Broken braces and stays, - - - - -

Seams leaking, ......

Total, 1,899 502

Summary for December.

During the month of December there were made 1,929 visits of inspection. The
number of boilers examined was 3,979, of which number 1,711 were annual internal
inspections.

The hydrostatic test was applied in 345 cases. 44 boilers were condemned.

The number of defects found foots up 2,226, 635 of which were considered of so seri-
ous a nature as to impair the safety of the boiler.

The defects in detail are as follows: —

Nature of defects. Whole number. Dangerous.

Furnaces out of shape, - - - - - 89-^-35

Fractures, 267 - - 138

Burned plates, - - - - - - 119 - - 39

Blistered plates, ...... 353 - - 63

Cases of deposit of sediment, .... 306 - - 65

Cases of incrustation and scale, .... 486 - - 55

Cases of external corrosion, ..... 160 - - 45

Cases of internal corrosion, - - - - - 94- -35

129

219

- 125

125

261

266 -

361

129

134

THE LOCOMOTIVE,

[February,

129

Cases of internal grooving,
Water-gauges defective,
Blow-out defective,
Safety-valves overloaded,
Pressure gauges defective,
Boilers without gauges,
Cases of deficiency of water,
Broken braces and stays,
Seams leaking,

Total,

2,226

635

Summary of the Inspectors' Report for the Year 1881.

During the year 1881 there were made 33,413 visits of inspection, being an increase
of 1,473 over the number made in 1880 ; the number of boilers inspected was 47,345, an
increase of 2,079 over the number inspected the previous year, while the number of
complete internal inspections foots up 17,590, an increase of 1,580 over the number made
in 1880. The hydrostatic test was applied in 4,386 cases, the majority of which were new
boilers. This is an increase of 796 over the business of the preceding year.

The total number of defects found which w^ere considered serious enough to be
reported w^as 21,110, of which number 5,801 were of a dangerous nature. This does not
include many defects of a less serious character.

The following table shows the defects in detail : —

Nature of defects.

Furnaces out of shape, - . . .
Fractures, ------

Burned plates, - . . - .

Blistered plates, - - . . .

Cases of deposit of sediment, . - .

Cases of incrustation and scale, -

Cases of external corrosion, - - .

Cases of internal corrosion.

Cases of internal grooving, ...

Water-gauges defective, - - - -

Blow-out defective, - . . .

Safety-valves overloaded, . - .
Pressure gauges defective,

Boilers without gauges, - - - -

Cases of deficiency of water, - . .

Braces and stays broken, - - - -

Seams leaking, -----

Defective heads, - - - . -

Loose tubes, - - - -

Mud-drums defective, - . . .

Dangerous defects unclassified, - - .

Total defects.

Boilers condemned,
Heads condemned,
Mud-drums condemned.

Whole number.

Dangerous.

1,164

301

2,417

1,414

1,180

426

3,360

468

3,753

532

4,082

494

1,346

450

899

266

335

128

•

401

157

255

132

396

169

1,647

375

553

128

101

478

313

31,110

5,801

363

1882.] THE LOCOMOTIVE. 21

The grand total of the work of the inspectors since the organization of the company
is as follows : —

Visits of inspection made, _...__. 186,109

Boilers inspected, -.-..... 378,463

Internal inspections, _---.-.. 125,750

Boilers tested by hydrostatic pressure, ------ 20,139

Total number of defects discovered, ------ 184,175

Total number of dangerous defects, -----_ 42,428

Boilers condemned, ._----■_ 2,200

We would call attention to the above record of defects discovered, and then most
respectfully ask : Is not the periodical inspection of steam boilers of some slight value ?
There can be but one answer to the above question, and that must be in (he affirmative.
It is impossible that a system of inspection which brings to light a total of nearly six
thousandi,6&ngerous defects in one year, can fail of accomplishing an incalculable service
to the steam users of this country.

Of the 17,590 different boilers which were internally examined by the inspectors of
this company during the past year, we find that 1,164 had defective fwmaces; this is one
in every fifteen on an average. This may not soem to be a very serious thing at first
sight, but when we stop to think what it means, the whole aspect of the question
changes.

Furnaces may be defective in various ways. In internally fired boilers they may be
too small and cramped, and as a rule, this is nearly always the case. This is probably
one of the most important defects to which this class of boilers is subject; but it is a
structural defect of such a character that it is not included in the above list of defects.
The defects there classified refer more particularly to the matter of blisters, bulged
plates, burned plates, fractured plates, and grooved or broken flanges. Blisters are one
of the most common defects met with, and one of the most difficult to guard against in
the selection of boiler plates.

A very careful inspection of the plates will sometimes discover imperfect welding
between the different laminje of a plate, which would almost certainly develop into a
blister under the influence of the intense heat to which it is^subjected in the furnace of
a steam boiler. The most common way to search for such defective places, is to tap the
sheet lightly all over with a small hammer. This must be done on both sides of the
plate, for sometimes the defect lies so neax the surface that an examination of one side
of the plate will fail to reveal it. Sometimes when there is doubt in regard to the qual-
ity of a plate and the preceding test fails to resolve it satisfactorily, the plate may be
suspended by the comers by means of cords, and the upper side evenly sprinkled
with sand, and then the under side being tapped lightly with the hammer, the move-
ment of the sand will reveal the presence and locality of the defect.

In many cases however, in spite of all precautions, defective sheets will be put into
boiler shells, and when they are exposed to the action of the furnace heat, blisters are
sure to result. In many cases blisters never become serious ; after attaining a certain size
they cease to enlarge, and remain so for years. In other cases, however, they continue to
enlarge rapidly, and unless their progress is arrested, serious trouble may result. When
a blister appears on a boiler-plate it should be carefully examined at once, by some one
who is competent to judge of its probable thickness, and form an opinion as to whether
it may be likely to lead to serious consequences or not. If it is of a serious nature, it
should be at once smoothly trimmed off" with a chisel. This will generally, but not
always, prevent further spreading and mischief. Sometimes they will continue to
spread after they are trimmed, and penetrate the plate so deeply that they have to be

22 THE LOCOMOTIVE. [February,

cut out, and a patch put on the plate in their place. Case8 have been known where even
after these extreme measures have been resorted to, the blistering has continued beyond
the edge of the patch to such an extent as to necessitate the removal of the entire sheet.
Blisfers are liable to occur on any part of a boiler-shell which is exposed to the action
of the heated products of combustion, but the furnace plates are oftener affected than
any other part, for there the heat is greatest.

Bulged plates may result from various causes. Insufficient bracing is a very common
cause of bulged plates, as well also as broken braces and stays. The writer knows of a
case where the braces of a f" thick crown-sheet, intended to carry a pressure of from 60
to 80 pounds per square inch, were pitched 12" apart. The result may be imagined. A
very few days' service sufficed to bulge the plate between each and every brace, to the
extent of al)out 2", and then it was thought best to remove the plate, and substitute
another and better braced one. Cases of this kind are quite common.

Broken traces^ unleps the defect is soon discovered and repaired, are almost certain
to result in serious consequences. If the braces of a crown-sheet are unskillfully put in, so
that one brace has an undue strain brought upon it, the sudden breakage, and the conse-
quent shock, may bring such an intense strain upon the surrounding braces, as to frac-
ture them in turn, and the entire crown-sheet may collapse. In this connection it may
be well to remember that a stress suddenly applied, produces a gfram just twice as great
as it would if applied gradually.

But the most fruitful source of bulged plates, as well, also, as hurned plates, is short-
ness of water. This may be brought about by various causes. Sometimes the jSreman
has such a multiplicity of duties to perform, that, through no fault of his own, he neg-
lects his boiler, and before he is aware of it, the crown-sheet is bare. In many cases,
especially where the water is bad, and too much reliance is placed upon the glass
water gauge, the pipes connecting the gauge with the boiler become filled with sedi-
ment to such an extent that all communication with the boiler is shut off: in that case,
while the glass gauge may show abundance of water, there may not be a drop in the
boiler itself, and the inevitable result is a burned and collapsed furnace.

In many cases where explosions have occurred, and the engineer and firemen have
sworn there was plenty of water, they may have based their opinion on the reading of
the glass gauge, and while they honestly enough believed Acre was plenty of water, there
might have been a great deficiency of it.

Burned and bulged plates are also caused by accumulation of scale or sediment on
them, which prevent contact of water, but as this matter is fully discussed in another
part of the issue, we will pass over it here.

Grooving of the flanges of the flues, and fracture of the furnace plates, are very com-
mon defects, and cannot be too carefully guarded against. Defective construction has
much to do with this class of defects, as for instance when flues are made either too long
or too short, and undue strains are brought upon the plates and flanges when the boiler is
put together. In this case the strains are greatly exaggerated by the expansion and con-
traction produced by the heat, and the opening of furnace doors, and in some cases, there
is no doubt that such strains have been so great as to cause sudden rupture of some part
of the boiler, which has resulted in explosion. Of course, such strains are further
aggravated by any buckling or distortion of the shell-plates.

In externally fired boilers, one of the most common defects met with is at the front
end of tlie furnace. The bricks over the furnace door are continually falling down, and
where the ends of boilers are set " flush " with the masonry, the extension of the shell
forming the smoke-box is very apt to be burned, and permanently injured. Overheating
of this portion of the shell causes leakage around the tube-sheet, which ultimately does
much damage if neglected. A very much better way is to let that part of the shell be-

1883.] THE LOCOMOTIVE. 23

yond the front tube-sheet, project beyond the masonry of the setting, and then no
damage can possibly result to it from the tumbling down of the Jire-bricks at front of
furnace. By this means, also, a much thinner wall may be used, and the mouth-pieces
correspondingly reduced in thickness, whereby the labor in firing is very greatly
reduced.

But the limits of our space forbid further comment. A volume might be WTitten
devoted entirely to the consideration of the steam boiler furnace, and the defects which
make themselves manifest therein. We will add a few words however, in regard to the
proportions of fiimaces of internally fired boilers. These are invariably made too small
to secure economical combustion. And there is no good reason why they should be
either. If the form of any boiler necessitates a cramped furnace, then that particular
style of boiler should be abandoned, or so modified as to admit a furnace of proper size.
"With large roomy furnaces, thin fires, and a due allowance of air both below and above
the grate bar?, all kinds of fuel may be burned without any trouble.

Relative non-conductivity of different substances.

Mr. Chas. E. Emery, of New York, recently made some experiments upon the rela-
tive non-conductivity of various materials with reference to the needs of the New York
Steam Company. His apparatus consisted of a boiler 12 feet long and 4 feet in diame-
ter, with 3 ten- inch flues passing through it. Inside these flues were smaller tubes
through which the steam passed ; the non-conductors surrounded the inner tubes, and
water was kept circulating around the flues in the outer shell. A layer of hair felt 2
inches thick gave the best result, and using equal thicknesses of the other materials the
following results were obtained : —

Non-conductivity.
Material. Per cent.

Hair felt, ---....-. lOO.

Mineral wool, No. 2, ------- - 83.2

Mineral wool, No. 2 and tar, --.---. 71.5

Saw-dust, ......... 68.

Mineral wool. No. 1, --- ..... 67.6

Charcoal, ......... 63.2

Pine wood across the grain, ....... 55.3

Loam, - - - - - -- - - - 55.

Gas work's lime, slaked, ....... 43.

Asbestos, --....... 36.3

Coal ashes, - - - - - - -- - 34.5

Fuel coke, --.-.._-. 27.7

Air space, 2 inches deep, ....... 13.6

The low result from air space no doubt is due to the unimpeded circulation of the
currents. The Iron Age.

Owing to the fact that certain scientific journals have made use of our monthly list
of boiler explosions, for the purpose of making up a summary and classification of the
explosions during the year, without giving us due credit, we have resolved to discon-
tinue publishing it monthly hereafter. We shall keep our record as usual, however, and
at the end of the year issue a special number of the Locomotive devoted entirely to ex-
plosions, which will contain a detailed list of the entire number, with a summary and
classification, with illustrations of some of the more destructive ones, and a discussion of
heir probable causes.

24 THE LOCOMOTIVE. [Febuuary, •

HARTFORD, FEBRUARY, 1882.

Many of the difficulties which arise in connection with steam boilers in use are not
understood by engineers in general, and, in fact, some phenomena cannot be accounted
for, even by experts.

The conditions under which a boiler is used have much to do with its behavior.
First, is it properly constructed, and are the parts so adapted to each other that there is
no undue or unequal strain brought to bear on any particular part ? This may arise
from improper bracing — having a greater tension on one brace than there is on its neigh-
bor. Joints may be so constructed that there is constant distress over their entire length.
If the holes for the rivets are not fair and the drift pin is used to bring them fair, there is
an unnatural strain brought to bear that is no part of its legitimate burden, and is not
provided for in the formulae used for estimating safe working pressures. These abnormal
strains are very much exaggerated when the boiler is under pressure and the load is not
evenly distributed. Hence, the portion bearing the excessive load, becomes a point of
weakness, and how weak can never be known until leaks, ruptures, or worse consequences
follow. Many boiler explosions are no doubt attributable to carelessness in construction.
The responsibility, therefore, resting upon boiler-makers is a very grave one.

It is not always easy or possible to detect defects in workmanship when a boiler is
finished and painted over with a coating of gas-tar, or some similar material. Another
difficulty is the water used. In many cases, no trouble arises from this source, while in
some sections of the country there is constant and serious trouble from water carrying
more or less lime or magnesia in solution, or from a combination of both with iron and
other ingredients. Hard scale or crust is formed on the fire-sheets, tubes, and flues, and
the efficiency of the boiler is greatly impaired, besides the damage from burning the
iron^thus destroying its strength. Carbonate-of-lime deposits as a fine jjowder under
about 180° of heat. In some sections it is so abundant that the w^ater becomes quite sen-
sibly thickened by it, and it interferes with the free escape of steam. Allusion is made
to this trouble in an article on another page, to which attention is called.

The sulphate-of-lime is a more serious difficulty, and not so easily overcome. It
makes a very hard scale, and, when once formed, can only be removed by hammer and
chisel. How to overcome this difficulty is a question not so easily answered, and we
would not venture to give a solution without knowing something of the circumstances
in each case. There is no universal " grand panacea " — difi'erent waters require as difi'er-
ent treatment as different diseases. As it is well to pay due regard to the laws of health
to prevent disease, and the more unfavorable the surroundings the more is care and cau-
tion required, so in this matter of bad water. Constant vigilance is necessary. A bottom
blow and a surface blow may be found of great service. Use them freely and frequently.
A solvent of tannate-of-soda, or some similar preparation that would not affect the iron
unfavorably, may be found serviceable. But this should be used intelligently. The en-
gineer should know what is being put into his boilers, and not take the opinion of every
vender of boiler compounds.

The fuel used is another subject for consideration, but as our space is limited we will
leave that for next month.

1882.] THE LOCOMOTIVE. 25

Obituary.

TuE death of Alexander Lyman Holly, the eminent civil and mechanical engineer,
has caused a world-wide sorrow. He died in Brooklyn, N. Y., January 29, 1882. He
was the son of Ex-Governor A. H. Holly of Connecticut. By his death the state loses
one of her most brilliant sons. He was a man that did things. He was not merely a
theorizer and dreamer, but he bent his energies to the accomplishments of great ends;
not merely for personal fame, but that he might do something of benefit to his country
and to the world. His spliere was a wide one. A new country with vast undeveloped re-
sources. He grappled with these problems and with what success, those know who are
familiar with his career. His works on American and Eurcxpean Railway Practice^ and
Ordnance and Armor, are familiar to those who are interested in such matters. But his
great work ^yas the intioduction and development of the manufacture of Bessemer
steel in this country. Much that is unwritten, and never will be written, was accom-
plished here. But the record is before us in the results. Every Bessemer Plant is a
monument to him — and every steel rail over which the flying train passes, rings out its
tribute to his memory. The noble sentiments which dwelt in his heart cannot be so
well expressed, as in his own words; the closing words of that memorable extempore
speech which he made in Pittsburg, in response to the presentation of a handsome testi-
monial from his friends.

" Among us all who are working hard in our noble profession and keeping the fires
of metallurgy aglow, such occasions as this should also kindle a flame of good fellowship
and alfcction which will burn to the end. Burn to the end — perhaps some of us should
think of that, who are burning the candle at both ends. Ah ! well, may it so happen to
us that when at last this vital spark is oxidized, when this combustible has put on in-
combustion, when this living fire flutters thin and pale at the lips, some kindly hand
may turn us down, not underblown — by all means not overblown — some loving hand
may turn us down, that we may perhaps be cast in a better mold."

The funeral services were held on February 1st, at Plymouth Church, Brooklyn.
The Rev. Henry Ward Beecher conducted the services, assisted by Rev. J. H. Twichell,
of Hartford, Ct.

A Case of Bagging Resulting from the Use of an Open Heater.

Editor Locomotive :

The article in September issue of the Locomotive, entitled a peculiar case of "bag-
ging," recalls a similiar case that came under the writer's observation some nine months
ago. I was sent for to examine a case of "bagging" in a boiler fifty-four inches in di-
ameter and twelve feet long, with a man-head plate under the tubes. The number of
tubes T do not remember, but the boiler was a new one, and wlien run one month the
sheet bagged, and the seams over the fire began to leak. The parties who built the boil-
ers re-riveted and calked them. The diflSculty was not overcome, and a new half sheet
was put into the boiler. This very soon l)ehaved in the same manner as the original
sheet had done. (The iron was Bailey's best Flange-iron, and no fault could be found
with it.)

The Ijuilder now concluded that the boiler was not kept clean, and requested that
when further trouble occurred the man-head be left in for him to remove, so that he could
see the inside of the boiler before any washing out or removing of sediment was done.
He was called when trouble again occurred, and upon opening the boiler found it very
clean, but it had " bagged " down and was leaking, nevertheless. He gave up the solu-
tion of the difficulty in disgust or despair. We were sent for to contract for a new boiler.

26 THE LOCOMOTIVE. [February,

but before doing so thought it best to make a careful examination of the case. I found
the water which was used impregnated with lime, and it was passed through an open
heater and lime extractor before going to the boiler. The parties assured us that lime
had never been deposited on the sheets of the boiler. We had suspected that this was
the cause of the trouble. The boiler was constructed in the usual manner, the tubes being
put in " staggered " rows, the nearest approach to shell being about two and one-fourth
inches, which, while nearer than we would recommend, did not, — considering the large
water-space underneath, — appear to hinder circulation. We refused to contract for a new
boiler until we found out what was the cause of the trouble. With a most diligent and
careful examination we could not assign a good reason for the trouble. But being pre-
judiced against open heaters, we allowed ourselves to be guided in a measure by our
prejudices. Our prejudices were based on the fact that tallow and grease from the en-
gine go freely into the open heater and mingle with the feed -water.

We recommended that the rivets be cut out from the leaky seam, and the "bagged "
portion set back as well as it could be, and then re-riveted. This was done. We also
recommended the open heater be disconnected and the boiler be fed with an inspirator
which we loaned them for the purpose of ascertaining if the changes would work any im-
provement. Everything being ready, the boiler was started up and has been running
every day since without leaking or " bagging." Now, what in your opinion was the
trouble? * * * *

The remedy applied seems to have been, the removal of the open heater. We have
often shown the troubles arising from the use of open heaters, particularly in portions of
the country where the formation was limestone. The writer of the above article says
that the boiler was clean and free from deposit or scale. If this was strictly so then the
trouble must have arisen from grease that found its way into the heater with the exhaust
steam, and thence into the boiler. We suspect, however, that when it is stated that the
boiler was clean, we are to understand that there was no hard scale on the sheets. Carbo-
nate of Lime, often deposits as a loose, fine powder, which when dried appears very much
like magnesia. This is sometimes of a light color, but more frequently by mixing with
the grease imparted to the water by the exhaust steam into the heater, it assumes a dark-
ish color. This settles down upon the bottom of the boiler, lies along the seams and
keeps the water from contact with the iron. Hence, very troublesome leaks and "bag-
ging " often occur from overheating. If the boiler is blown down hot this slush or sludge
will bake on to the hot sheets and form a scale. But if the fires are drawn, and fire-sheets
allowed to cool off, the sludge does not bake or burn on, and in drawing oflf the water it
will appear muddy. Boilers in limestone districts are often found with this sludge or
mud on the bottom inside, and if such was the case in the boiler above described it ac-
counts for the whole difficulty.

It is generally supposed that a deposit in a soft state causes little or no injury. This
irapalijable powder, however, is long held in suspension on account of its lightness, but
finally settles down on to the fire-sheets, and then trouble begins, especially if an open
heater is used. Many cases similar to the one reported above have come under our no-
tice, and in all cases the engineer has declared that there was no scale in the boiler, and
an examination has usually proved that there was no hard scale. But the sludge was there,
and the boilers were in almost all cases fed through open heaters. It will therefore be
seen that a hard lime scale (sulphate of lime) is not necessary to produce serious results.
But the light, almost impalpable powder of carbonate of lime is capable, under some cir-
cumstances, of doing immense mischief. Frequent blowing, — an inch or two at a time, —
will generally overcome the whole difficulty. We recommend a heater always, for we
believe the working age of a boiler is increased by a good heater. But an open heater
in carbonate of lime districts is almost sure to give trouble.

1883.] THE LOCOMOTIVE. 27

Still another "Prolific source of Boiler Explosions/'

The periodical " explosion idiot" has again put in an appearance, hugging his little
theory and then letting it loose upon a defenceless community. This time he " bobs up
serenely " through the columns of the Manufacturer'' s Gazette, and signs himself X. At

his
first we thought the signature was the usual symbol for John Smith X , but on second

mark

thought concluded that he had selected X because it was universally used to denote an
unknown quantity, and he thought the value of his ideas could best be represented in that
manner. Let us hope that this is the case, and also hope that X will resolve itself into
either § or 0, for we have now altogether too many mysterious and peculiar theories to
account for steam boiler explosions. What we are sorely in need of is, less theory after
boilers have exploded, and more right practice in their care and management before they
explode. This will obviate, in a great measure, the need of any theory to account for
explosions, for the reason that there will be few explosions to account for. We think it
is decidedly better to look out for thieves, in order to prevent their depredations, than it
is to lock the stable-door after the horse has been stolen.

The brilliant theorist in question leads off with the assertion that " many steam boil-
ers explode from no apparent cause, and become the subject of various speculative
theories." We must beg leave to differ with the gentleman in regard to the first part of
the above quotation, for the records of the investigation of explosions flatly contradict
it; but with respect to the last part of his statement, that "they become the subject of
various speculative theories" we heartily and entirely agree with him. If there teas any
doubt on the subject, a perusal of his own article w^ould instantly dispel it. His next
statement is : " The fault is generally ascribed to some imperceptible defect in the boiler."
Of course. That is an easy way to account for a boiler explosion. The mental strain
involved in ascribing " some imperceptible defect" to the boiler, is far less than that
involved in an examination of the fragments to discover the true cause, or even in
inventing a new " theory " to account for it. Therefore, it is very often done. And
besides defects are always " imperceptible " until they are discovered. Therefore it is
sometimes an advantage not to discover them. So it will be seen that the " impercepti-
•ble defect" theory is very convenient sometimes.

Continuing he says : " In order to ascertain what I regard as a prolific source of
boiler explosions we must first consider the nature of steam. This we learn from the
way it is produced. I contend that the principle underlying the whole matter is the
peculiar affinity which the water possesses for heat at 212°. The unit of heat, rising
from the boiler fire, is incased by a thin shell of water. On reaching the top of the
water and encountering colder air, the shell breaks and the heat escapes."

We will give a chromo to any one who will satisfactorily explain the third and
fourth sentences of the above quotation. We confess our entire inability to penetrate the
deep and awful mystery hidden beneath the above apparently simple words.

If the affinity of water for " heat at 212° " is as " peculiar " as the above language,
then it must be a very surprising thing indeed. And the writer's conception of the
nature of the " unit of heat" is so marvelous in its simplicity, and so sublime in its ridicu-
lousness, and is so "utterly " different from our own conception of it, that we are almost
led to believe that Dr. .Joule is a mythical personage, and the published results of his
investigations some horrible fiction invented by evil disposed persons for the pur-
pose of deluding poor humanity into a belief which shall eventually lead to their utter
destruction.

Further on he says: "As we increase the pressure, the heat increases in definite
ratio, an;! as the pressure increases, the steam-globules are compressed. This action goes

28 THE LOCOMOTIVE. [February,

on until the pressure of the globules in the steam space becomes equal to the pressure
exerted by the fire, when ^team ceases to form."

This is really something new in the manner of generating steam. Alas for the
fondly cherished traditions of our childhood ! We had always been led to believe that
as we increased the heat, the pressure increased; but now we are forced to admit that
we have all along had " the cart before the horse ; " the laws of nature all work back-
ward, and " the heat increases as the pressure is increased." And the idea that steam
pressure is produced by the pressure of the fire is decidedly novel and refreshing. We
shall never dare to open a furnace-door again for fear that the immense pressure, exerted
by the fire, will blow us into " kingdom come " heels over head, which would be very
awkward to say the least.

But here perhaps we have a hint for a method of making boilers perfectly safe, re-
gardless of such trifling things as inoperative safety-valves, fractured plates, broken
braces and all such defects which are generally supposed to lead to the failure of boilers.
Our plan is this : Let the boilers be set so that they are entirely surrounded by the fire, then
the " pressure" of the fire on the outside, will just equal the pressure of the steam on the
inside, and so of course there will be no tendency for the boiler to explode. We furnish
this hint gratuitously for the benefit of a sufifering community.

He continues : " Now, here we have a boiler, capable, we will suppose, of with-
standing 500 pounds pressure to the square inch. In the furnace the fire is equal to the
maintenance of 200 pounds pressure in the boiler. (That is, we suppose he means that
the " pressure " of the fire is 200 pounds to the square inch.) Everything is working
smoothly ; the engine taking a regular amount of steam and leaving 200 pounds pressure
in the boiler."

"Now let the steam be cut off from the engine. What is the result? The steam
keeps on forming, and the globules will accumulate until the pressure they exert is equal
to the " pressure " of the fire. The two forces being equal, action ceases. The boiler,
however, will bear a pressure of 500 pounds, and the steam gauge does not register any-
where near that amount. Therefore it may be said that no danger is to be apprehended.
But there is a subtle force at work all this while. It is true that steam is not being
formed actively ; but the heat is entering the water and is absorbed by it. It cannot
convert it at once into steam, for its force is balanced fey the force of the compressed
steam globules above. But suppose that steam is now let into the engine. The pressure
is suddenly relieved. The steam at the top rushes out and the " latent steam," as we
may call it, rises from the water, asserts its real character, and more than fills the room
which has been made for it. * * * * -phe result is an explosion."

Funny, isn't it, how very easy it is to "bust a biler" on paper, with the aid of one of
these little 4 by 6 double-ended, patent back action, muchly hypothecated theories.
According to this noble theorist, we have only to stop an engine and start it up again
after a few moments, to infallibly produce an explosion. This we are deliberately asked
to believe in the face of the fact that tens of thousands of engines are daily and hourly
shut down, and started up again all over the world without " starting a hair." We have
heard of many wild and startling theories to account for boiler explosions, but the above
is about the most jumbled up and asinine production that ever came under our observa-
tion. Observe the colossal calmness with which he makes the contradictory statements
that, " the two forces being equal, action ceases * * * * i^uj ^ j^g j^ej^t jg entering the
water and is absorbed by it." We always supposed that as long as heat continued to
enter the water, the pressure would continue to rise ; but such it seems is not the case,
especially, where the above theory is applied. After the pressure of the steam is equal
to the "pressure" of the fire, we may super-heat our water as much as we please. This
discounts the Donny theoiy, and then comes in a long way ahead.

1883.] THE LOCOMOTIVE. 29

But what is now to become of the " rival " theory, that shutting down the engine
causes the boiler to explode ? Engines are stopped, as often as they are started, and the
boilers seem to be as apt to explode in one case as in the other, so that the two theories
seem to be about equal as regards efficiency. This being the case we suggest that the
rival theorists hire a hall and be left to themselves to settle the question of merit. We
are confident that this is all they are good for. h. f. s.

Reversing Filters.

It is bj no means clear that the reversing process somewhat used in filtering appa-
ratus, or even blowing back through them with steam under pressure, is really efi"ective
in the cleansing of the filtering medium which is employed. This method, with various
modifications, has been practiced for many years; but when large masses must be treated,
or the finest grade, as it may be termed, of filtering is to be provided for, then recourse
is had to the old-time open sand bed, or to the vessel filled with animal charcoal — that
lie plus ultra for the manufacturer or painstaking housekeeper.

In the large majority of cases the sifting out from the water of the sediment
mechanically suspended in it, is all that is or can be attempted, and hence the material
of which the filter bed is made up is selected and laid into the filter with this particular
object in view. The process of filtration is thus the lodgment, in or upon the fragments
or particles of this filling material, of the fine silt or sediment borne by the water as it
passes very slowly through. The cleansing process aimed at, or proposed, in the revers-
ing movement is the dislodgment, or washing oft' and bearing away out of the filter, of
this sediment ; but as this washing off" and away necessarily implies or involves a rapid
movement of the washing current, it is quite obvious that in the reversing filters a self-
contradiction is often attempted. The upturning or disarrangement of the closely-packed
filtering material, which to act perfectly needs to be undisturbed, is the last thing that
should be attempted in an apparatus* which is expected to be durable and permanent in
its action. The fact that this cleansing movement of the reverse flow to be useful must
be rapid, is shown by the method so often practiced in the management of open filter
beds in regions where this sand or gravel material is scanty, and that which has become
foul in use must be washed and repacked in the filter. In such cases the vigorous stirring
up or agitation of the silt-covered sand particles in a flow of water alone suffices to restore
their efficiency, the cleansing thus accomplished being clearly impracticable in the very
slow current which alone is possible in any reversing device.

In reference to the use of filtering apparatus in general, it may be said that it is far
too little valued and employed. Men take great pains, or some men do, to secure coal or
coke for their work which shall be as free from ash as possible, while in the same imme-
diate connection a water supply is employed, which, though it may be cleansed from
serious or even dangerous impurity by simple and inexpensive means, is nevertheless
accepted and used as if the art of filtering had never been practiced, or, indeed, had
never been heard of. — The Iron Age.

Mr. Jamrs Emerson of Holyoke, Mass., has prepared a Treatise, relative to the
Testing of water-wheels and machinery. It has the records of experiments made at sev-
eral of tlie large water-powers in the country. It also describes the various water-
wheels in use, and the attachments and appliances used in connection with them.
Altogether it is a valuble Compendium of Hydrodynamics, and should be in the hands
of every person interested in the subject.

30 THE LOCOMOTIVE. [Februaky,

Celling up Sleam.

The records of boiler explosions demonstrate unmistakably the importance to the
steam user of the most careful supervision over boilers at the time of getting up steam.
Some of the most destructive explosions of which I have any knowledge, occurred either
on Monday morning, or at the time of getting up steam after the boilers had been out of
service, while cases in which plates are bulged, furnaces distorted, and flues and
tubes badly injured, are of quite frequent occurrence, all due to ignorance or careless-
ness, or both, in getting up steam, or neglect of necessary precautious in filling boilers,
or having filled them, a failure co detect leaky gaskets, imperfectly closed blow off
valves, or cocks that had permitted the escape of the water before fires were lighted.

An old shipmate now chief engineer of one of our largest steamship linep, of extended
experience among engineers and thoroughly practical in every department of the steam
engineering service, used to say there were few among our best engineers who properly
understood how to charge a furnace and get up steam. All things considered, he re-
garded that job when well done, as one of the most important duties in the business,
and of sufficient importance to be done by the engineer, or at least immediately under
his direction, and not as is commonly the case intrusted to a fireman.

Filling boilers, charging furnaces, and getting up steam, are considered very ordi-
nary duties by most engineers, who would smile derisively, if it were intimated that they
did not understand those duties ; perhaps they do, if so, it must be confessed many of
them have a queer way of showing it.

In filling boilers, I have found it a good plan to raise the eafetj'-valve and block it
open; this will permit the escape of air, besides indicating the time boilers begin to
steam, after which the valve may be lowered. I have observed most stationary engi-
neers in charging furnaces, put the kindling wood on the grate bars; another and I
think a better plan is to first scatter a thin layer of coal all over the bars, atop that
the wood is placed ; the latter plan if tried, will be found a more economical and expe-
ditious way in obtaining a good bright steaming fire.

The masonry or setting of externally fired boilers now almost universally employed
in our larger cities where aqueduct water is used, is frequently ruined by heavy forced
firing, when steam is first got up — the cement and mortar instead of being allowed to
set properly as they would do if slowly and judiciously heated, speedily crumble away,
losing the strength of the joint, the brick-wall cracks open, the draft is impaired, heat
lost, and perhaps the girth seams of the boilers strained by the unequal settling of the
walls. In a few months it is necessary to reset the boilers again, for which the innocent
mason may be cursed loud and deep, the engineer in all probability being his chief
accuser.

Forced firing is not only injurious to the setting, but to the boiler as well ; this is
most apparent in the use of the common upright or vertical tubular boiler, in which the
water is carried some distance below top of tubes ; the tube-heads soon begin to leak
and require frequent expanding in order to keep them tight; it will be found a good
plan when troubled in this way to have defective tubes fcrruled. Horizontal tubular
boilers are often set to return heat over the top of shell ; the disadvantage of this plan of
setting is the danger of the exposed shell above water line, being injured in getting up
steam from cold water; the shorter the boiler the greater the danger of injury, the lower
part of boiler being at a temperature due to that of the contained water, while the upper
part is exposed to that of the escaping products of combustion. A recent experience
was that of three boilers 42" X 10' used for heating purposes only, at a pressure never ex-
ceeding 25 lbs. Yet under these favorable circumstances they were ruined in about five
years. More or less trouble had been experienced during the preceding season from
leaks above the water line. On examination it was found that the upper half of shell

1882.] THE LOCOMOTIVE. 31

was badly cracked in several places, and when it was attempted to cut out the defective
sheets, the surrounding metal was found so brittle and badly crystallized, the boilers were
condemned. The shells below water line had never given any trouble and appeared to
have suffered no injury during their brief service. There can be no doubt, I think, their
failure was due to the plan of setting, for they were built by one of our best boiler-makers,
of selected iron, and while in service were under the care of a first-class engineer ; under
less favorable circumstances their failure would have occurred sooner. Fractures in the
sheets of boilers set in this way are of common occurrence, the danger increasing with
the frequency of getting up steam.

In some f)arts of the country local ordinances for smoke prevention are now in force,
and many worthless smoke-burning appliances (so called) have been sold to steam users in
those localities. A roomy furnace, ample combustion chamber, and a clean bright even
fire not exceeding eight inches thick, with systematic firing will be found helpful in les-
sening the smoke nuisance. When there is more than one furnace, the firing and clean-
ing must be alternated, the fireman having his fire tools within reaching distance, and
damper closed before he opens furnace door, which must be closed again as quick as
possible.

There are two principal methods of firing known to the initiated, as "spread firing"
and '"side firing." Each has its advocates, who are convinced their's is the only plan.
I have practised both, and so far as I could tell with about equal results; am inclined to
attach greater importance to having an experienced fireman, careful attention, regularity
of firing and rapidity of movement, than to any prescribed form of covering the fire,
which must of necessity varj' in different localities according to the quality of the fuel.
But a Careful attention to the details enumerated, will result in economical consumption
of fuel, lessening of smoke, and greatly increased efficiency of the boilers wlienever
practised. F. B. Allen.

In our last issue, page 3, second line below cut, in the calculation of the working
pressure of the boiler the expression ''^^W" ■"» = 1^ = 70," would perhaps have been
less liable to be misunderstood by those unfamiliar with the calculation of the strength
of steam boilers, if it had been written " ^'^"°° ' •'» — 420, and this divided by 6 =70 lbs."
&c., where 6 is the factor of safety.

The Association of Proprietors of Steam Engines in the North of France, have
made numerous experiments which show that many of the bricks that are employed in
building furnaces are so porous as to allow an easy passage for air. In consequence of
these experiments, they advise that no bricks should be employed for the purpose which
are not very compact and refractory, and that they should be either glazed upon the out-
side, or covered with an impenetrable varnish. The Iron Age.

Mechanics is the name of a new publication issued by David Williams, the well known
publisher of the Iron Age, Carpentry and Building, and the Metal Worker. The opening
numV)er8 are full of choice reading, and we predict for it a brilliant and successful career.

THE LOCOMOTIVE.

[Februaky.

Incorporated
1866.

Charter Per-
petual. .

Issnes Policies of Insnrance after a Careful Inspection of ttie Boilers,

COVERING ALL L08B OK DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

AEiaiNO FROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full information concerning the plan of the Company's operations can be obtained at the

Or at any Agency.

J. M. ALLEN. Prest. W. B. FRANKLIN, Vice-Prest. J. B. PIEECE, Sec'y.

Board of Oii-eotors 2

J. M. ALLEN, President.

LUCIUS J. HENDEE, Preat. Mtn& Fire Ins. Co.

FRANK W. CHENEY, Treas. Cheney BrotlierB Silk

Manufacturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Amer. Nat. Bank.
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Manufacturine Co.
THOMAS O. ENDERS, of.£tnaLlfeIn8. Co.
LEVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Hon. HENRY C. ROBINSON, Attorney at Law

Gen. WM. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire
Arms Mfg. Co.

GEO. CROMPTON, Crompton Loom Works, Wor-
cester.

Hon. TH08. TALBOT, Ex-Goveruor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manufacturer, Provi-
dence, R. I.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. PARRY, of Baldwin Locomotive Works,
Philadelphia.

GENERAL AGENTS. CHIEF INSPECTORS.

THEO. H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKIM,
W. S. CUAMBERLIN,
J. L. SMITH,
H D. P. BIGELOW,

C. C. GARDINER,

D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

R. K. MoMURRAY,
WM. G. PIKE,
JOSEPH CRAGG,
WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN,
J. H. RANDALL,
A. C. GETCHELl^
J. S. WILSON,

OFFICES.

New York Citt. OflSce,
Philadelfhia. "

Baltimore. "

Boston, Mass. "

Providence, R. I. "
Chicago, III. "

St. Louis, Mo. "

Hartford. "

Bridgeport. "

Cleveland. "

Cimoimmjlti. "

285 Broadway.
430 Walnut St.

10 So. HoUiday St.

10 Pemberton Sq're.

1 5 Weybosset St.
132 La Salle St.
404 Market St.
218 Main St.
328 Main St.
246 Superior St.

58 West Third Si.

8fe

0C0m0lto^.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series— Vol. III. HARTFORD, CONN., MARCH, 1882.

No. 3.

Boiler Construction and Setting.

We present" below, Fig. 1, a drawing of a Horizontal Tubular boiler with attach-
ments and setting, which was designed by The Haktford Steam Boiler Inspection
AND Insurance Company.

The proportions of this boiler are somewhat at variance with the present practice
among boiler-makers, and we would not recommend its adoption except after careful
examination of all the surroundings. The quality of water and fuel used are important
considerations — also the draft. The dimensions of the boiler are as follows: 21 feet 4
inches long outside, 66 inches in diameter. Tube-heads 20 feet apart. 54 tubes, each 4
inches in diameter. The front is known as the " cutaway " projecting front. The braces
are attached to pieces of T iron arranged radially on each head, as shown in Fig. 2.
The heads above tubes are stiffened by these pieces of T iron. There are two nozzles,
one for safety-valve, and one for steam.

The boilers arc constructed of steel plates f inch thick. Heads, steel ^ inch thick.

Horizontal seams double-staggered riveted.

The setting is so planned, as to secure the best effect of the radiant heat, at the same
time tliere is ample provision for a projier mingling of the gases with atmospheric air.
The ash-pit bottom is a water basin, in which four or five inches of water are constantly
kept. No ashes or cinders should be allowed to accumulate there, but should be raked
out as often as the fire is cleaned and replenished. The boiler is supported on lugs, so as

THE LOCOMOTIVE.

[Makch,

to leave the bottom free from any obstructions, and to give the inspector ample room
and opportunity to thoroughly examine the fire-sheets.

These boilers are working fully up to our expectations. The gases are well-consumed,
and with soft coal, very little smoke is ever detected issuing from the chimney. Properly
constructed, and properly set, we regard it as one of the most economical, and easily-

managed boilers in use.

Inspectors' Reports.

January, 1882.

The following summary shows the work of the inspectors of this Company for the
initial month of the year. It compares very favorably with the corresponding month of
last year. From it we learn that the number of visits of inspection was 2,001, by which
4,292 boilers were inspected. The number of boilers thoroughly examined both inter-
nally and externally was 1,303, and the number subjected to hydrostatic pressure was
312. The number of boilers condemned was 17.

The number of defects found was 1,550, of which number 409 were considered dan-
gerous. The following statement shows the defects in detail : —

Nature of defects. Whole number. Dangerous.

Furnaces out of shape, - - - - - 72 - - 19

Fractures, - - - - - - - 209 - - 138

Burned plates, - - - - - - 68 - - 2J

Blistered plates, ------ 240 • - 38

Cases of deposit of sediment, .... 188 - - 23

Cases of incrustation and scale, .... 330 - - 31

Cases of external corrosion, - -.-- 94 --24

Cases of internal corrosion, - - - - - 68- -14

Cases of internal grooving, ----- 9--6

Water-gauges defective, ..... 41 '-ID

Blow-out defective, - - - - - - 18- -11

Safety-valves overloaded, ...-- 23 --9

1882.] TH*E LOCOMOTIVE. 3t»

Safety-valves defective,
Pressure gauges defective,
Boilers without pressure gauges,
Cases of deficiency of water,
Broken braces and stays,
Cases of serious leakage.
Heads defective,

Total,

131

1,550

409

Fractured ptates are very common, much more so than is generally supposed to be
the case. In the above list, only those of a serious character are reported. Fractures
are found in all parts of boilers, and their location and appcaijance will generally be
sufficient to indicate their probable cause to an experienced inspector.

The nature of the iron of which plates are composed, of course influences very
much the liability to fracture, as does, also, the treatment which the iron receives at the
hands of the boiler-maker, and the after treatment which it receives wlien the boiler is
in use.

One prolific source of fracture in boiler-plates lies in the pernicious habit of leaving
the damper wide open while slicing the fire, or adding fresh coal. A current of cold air
is drawn into the furnace, and impinges on the under and highly-heated side of the
boiler shell, causing sudden and violent local contractiim, which is sure to strain the
girth-seams, and in many cases rupture the shell. Cases have occurred in the experience
of this company where boilers have been exploded in tliis manner with disastrous results,
when there was no fire at all under them. This may seem strange, but it is nevertheless
true. In one case which occurred in 1879, a battery of boilers were in use, and were all
connected to one steam-pipe. Some of the boilers were heated by the waste gases from
puddliug-furnaces, and when the furnaces were stopped, and fire out for a night, it was
customary to leave the stop-valve open, so that steam from the other boilers might
k( ep the water warm. In this case there was steam at a pressure of 70 pounds per
square inch, the temperature of which would be about 316 degrees Fahr., acting on the
upper half of the boiler, while the lower half was exposed to the current of cold air
drawn through by the draft of the chimney. It may easily be seen that l:he contraction
thus caused would be quite severe. It was so great in this instance that it caused the
boiler to leak badly, and the water tender, an ignorant fellow, pumped in a lot of cold
water. This was the straw that broke the camel's back, and away the boiler went — a
genuine explosion where there had been no fire for several hours. It will readily be seen
from this, how important it is to avoid sudden cooling of any part of a boiler-shell.

The practice of feeding cold water into a boiler and delivering it near the shell,
cannot be too strongly condemned. Boilers fed in this manner invariably leak at the
seams near where the water is delivered, and show other unmistakable signs of distress.
If the use of cold water is unavoidable, a " circulating " feed-pipe should always be
used. This is a pipe entering horizontally through the front head, near one side, a few
inches below the water-level, thence running back to within one or two feet of the back
head, then crossing over to the other side of the boiler and projecting downward between
the tubes and side of the shell. The water is thus caused to traverse the entire length,
and nearly the whole widtli of the boiler, and is finally delivered downward into the
coolest part of the water. By this means it is heated nearly or quite to the temperature
of the main body of water in the boiler, before it can possibly come in contact with any
part of the shell, and so the evils of violent contraction are entirely obviated. Of course
where an injector or feed-water heater are used all the time, this is not so essential.

Fractures frequently occur at the girth-seams of long boilers such as are found in

36 THE LOCOMOTIVE. [March,

iron works. These are frequently made as much as 30 feet long, and not over 3 feet in
diameter, with supports at the ends only. It will readily be seen that under such cir-
cumstances the strain on the girth-seams near the center of the boiler must be very great,
whenthey are full of water. Boilers of the above proportions should always have more
than two supports, and those near the center should be so constructed as to always bear
their due share of the weight of the boiler, as its position varies from the effects of
expansion. This subject, however, has been fully discussed and illustrated in preceding
numbers of The Locomotive, so we need say nothing more about it here.

One of the most frequent cauc^es of fractures at the seams of boilers is the use of the
drift-pin. Where the rivet-holes in a seam fail to match in a direction parallel to the
length of the seam, and the drift-pin is used recklessly, JV'c frequently find the plate
cracked from a dozen rivet-holes consecutively, running from the side of the hole to the
edge of the plate. Sometimes the cracks will never extend beyond the rivet-holes; in
this case they may give comparatively little trouble if the seam does not leak, if it
causes leakages at the seam, or if any of the cracks extend beyond the rivet-hole into the
plate, then the matter may become serious.

When the rivet-holes fail to come fair in a direction at right angles to the length of
the seam, and the drift-pin is used, then the fracture runs from one rivet-hole to another,
and thus forms practically one fracture. This is always a serious matter, and should
always be attended to at once.

Sometimes the location of boilers is such, that the upper side comes on a level with
some floor where it is convenient to stow articles in process of manufacture. We know^
of places now where flag-stones have been laid over the tops of some large boilers, and
several tons of goods are piled up on the place every night. The inevitable result has
been to fracture each one of the boilers in its turn, as well as to keep the girth-seams in
a chronic state of leakage.

Mechanics says ; " Mr. D. T. Lawson, whom our readers will remember in connection
with experiments made some time since in boiler explosions at Pittsburg, has recently
been doing something further in the same line. The present series of experiments are
made to show that a boiler fitted with his patent explosion preventer cannot be burst. We
believe there are two boilers precisely alike, save that one has the patented device, and
the otlier is without it. One of the experimental boilers is to be exploded, and the other
is expected to resist all eff'orts to do so. The latest experiments show that both of the
boilers stood the tests remarkably well, the gauges showing about 275 pounds, but as a
gasket blew out soon after this pressure was reached, the experiments were pronounced
undecisive. Mr. Lawson might conduct his experiments in a much more conclusive
manner if he would use smaller pressures and larger boilers. If he will get an old pair
of condemned marine boilers capable of holding a large quantity of water, even though
they would not stand more than twelve or fourteen pounds of steam, he could get uyi an
explosion that would astonish all concerned, and demonstrate conclusively whetJier his
apparatus had any value."

And we are of the opinion that if he will get an ordinary boiler in good condition,
and use the ordinary working pressure, he will find it utterly impossible to explode it in
the manner in which he is now experimenting. Furthermore, if he will get an old, badly-
used, muchly worn out boiler, with safety-valve stuck tight, braces broken, and all steam
outlets closed, and fire it up, he will find it entirely unnecessary to open his steam-valve
suddenly to produce an explosion.

1882.] THE LOCOMOTIVE. 37

$f $

HARTFORD, MARCH, 1883.

The Brooklyn Boiler Explosion.

On the 16th clay of February, 1883, about half-past eleven o'clock, two of the boilers
of the Jewell Milling Company of Brooklyn exploded with terrific force, doing great
damage to the building, and killing the engineer. These boilers were insured by The
Hartford Steam Boiler Inspection and Insurance Company, and.had been, since June, 1880.
The boilers were made by the Woodruff & Beach Co., of Hartford, Conn., whose reputa-
tion for first-class work is well-known.

The boilers were of the type known as " Drop Flue," 21 feet long, 7 feet in diameter,
thickness of plates ^^g-inch originally. Internally fired. There WTre 17 flues; 4 were 13
feet long and 16 inches in diameter, and 13 were 9 feet long and 9|- inches in diameter.
Tlie boilers were built in 1861, and had been used since that time under the care of a
competent engineer. They were internally and externally inspected in June, 1880, when
they first came under the care of this company, and were found in bad condition. Pre-
vious to this time they had been under the care of the city official, whose inspection
consisted mainly of the hydrostatic test. It was the careful internal and external inspec-
tion of this company that discovered the defects, and repairs were ordered. These repairs
consisted of new furnace-sheets, extra and renewed bracing.' The owners applied for 90
lbs. of steam, but that of course could not be allowed. When the repairs were completed
the boilers were again examined, and it was decided that 45 lbs. might be safely carried.
The safety-valve was loaded at 50 lbs. to prevent steam constantly blowing oft", if the
pressure reached 45 lbs. The safety-valve commenced to blow at 48 lbs. by the gauge.
Quarterly visits of inspection were made while the boilers were in use to see if everything
was in good condition, safety-valve free, and steam-guage correct. In June, 1881, another
internal and external inspection was made, — thorough and complete, — and no change
material to the risk was discovered.

In examining the parts of the exploded boilers, it was evident that the incipient
rupture was not at the theoretical weakest point. It did not commence at or along the
longitudinal seam, but began at the drop connection, and followed along at the girth or
"roundabout" seam. The boilers were supported from a girder in the rear, and rested
on a wall or foundation in front. The peculiarity of the fracture indicated the presence
of some strain other than that caused by internal pressui'e. The settling of the founda-
tions has been suggested, and in studying the locations and surroundings there appears
to be good ground for such an opinion. The buildings are located on a dock of "made
ground," driven thick with piles so as to secure a foundation.

The chimney settled some time ago, and it became necessary to fasten it to the walls
of the building by iron rods or straps, to hold it in position. Tiie foundations of the
engine have settled once or more, and it has been necessary to relay or readjust them.
The boilers were located outside the main building, and nearer the water's edge than
either the chimney or engine. Now a slight settlement of the foundations of the support
at either end would cause a strain that might ultimately result in fracture, and the rup-
ture once started, the rest is easily accounted for. It might be said that the settling of
chimney and engine foundations should have called the inspector's attention to the boiler-
foundations. But those familiar with the business can readily see that it would be no
easy defect to discover, and the influence of heavy rains, and high tides, may have been

38 THE LOCOMOTIVE. . [March,

an element in the problem. The public can rest assured that this company does not, nor
can it afford to, make careless inspection of the boilers under its care. It has every
incentive to be especially particular and careful in its inspections. It has been doing
business in the Metropolitan Department for fifteen years, and this is the first explosion of
any boiler there under its care during that time. Durins this period there have been some
ten or twelve explosions in the Department, all of which we believe were under official
inspection, and it is proper to state here, tliat in the year 1881, the company insured some
15,000 boilers, only two (2) of which exploded. If any other system can show a better
record, we should be glad to hear of it. It must not be forgotten that manufactories of
all kinds in the country are being driven to their utmost capacity at the present time, and
in this case it appears that there was a constant demand on the engineer for more steam.
Many people have the impression that so long as the pressure of steam is not increased
the "wear and tear" of the boiler is not increased. This is erroneous. The wear and
tear is mainly dependent upon the amount of water evaporated. If the demand for steam
is such that the fires must be constantly forced, the boiler will feel the effects in every fiber.
To illustrate: A horse may be able to draw a ton or more on a good road with ease for
hours, but if you urge him and make him trot, or run, he will soon give out. A man
may be loaded up to his full capacity with work, and he will do it easily, but if you
drive and fret him, he will soon fail and break down.

The report of this explosion was spread far and wide through the public press, and
no opportunity was lost to cast odium upon this company.

"We do not lay this up against the press. For it is their business to get all the items
of news they can, and the more sensational, the more attractive with the reading public.
But it is not perhaps generally known that the office of Thos. F. Powers, Boiler Inspector
for Brooklyn, is in the same building as that of the associated press. Nor is it perhaps
known that his animus has been anything but friendly towards the company for some
time.

Under these circumstances it will require no severe stretch of the imagination to ac-
count for the statements sent out over the country. It was stated that Powers had con-
demned the boilers ; that he had said they were 'not safe for 30 lbs., that there were
many boilers in his department insured by the company which he w^ould condemn, etc.,
etc. The facts are, that the boilers were placed under the'company's care by the Jewell
Milling Co. because "they did not consider the local inspection a safe one, that is, the
mode of inspection." This is Mr. Jewell's testimony before the coroner's jury. When
the boilers first came under the company's care it would not insure them at any pres-
sure, but after thorough repairs were made they were willing to insure them. When
Powers examined the boilers only 30 lbs. pressure were wanted. He testified thus: "We
examined these boilers in question on June 22, 1879, and made the test by means of
hydrostatic pressure ; the result of my examination was that they were in good condition.''''
Further on in his testimony he says: " In order for me to give my op'mion whether 50
pounds of steam would le snfe, I tcoidd again have to test the boilers.''^ This don't read
much like the stuff sent out over the country as Mr. Powers' statements mentioned above.
The testimony of Chief Engineer Sewell, of the U. S. Navy, was emphatically in favor of
the hammer test as against the hydraulic test. He also stated that he had figured up the
pressure, and did not regard that used at the time of the explosion as excessive. The
inspectors of the company who made the inspection gave a clear and intelligent account
of the process in detail, and Chief Inspector Mcilurray presented specimens of the iron
which had been cut from the plates of the boiler at the fractured edge. These were test-
ed by the Colt's Arms Manufacturing Company, and showed a clean fibrous fracture with
a tensile strength varying from 40,400 lbs. to 48,940 lbs. Four tests were made. There
was no evidence whatever given to warrant the verdict rendered.

1882.]

THE LOCOMOTIVE.

This opinion has been repeatedly expressed to us, and it is characterized by those
who have good reason to know as a " put up job " to influence legislation against the
company. We are informed by an eye witness that when the evidence was all in, coro-
ner Keller proceeded to sum it up and charge the jury by taking from his jmcket a docu-
ment all prepared, and which, from the difficulty that he had in reading it, was evidently
written by some other person, and before the evidence had been given. It is said that all
through the investigation there was unmistakable evidence that the coroner and jury had
prejudged the case from the start.

The Emery Testing Machine at the Waterlown Arsenal.

We have read with no little interest the letter of Col. T. T. S. Laidley, U. S. A. Com-
mandant at Watertown, to the Iron Age, giving an account of the work being done on
the Emery Testing Machine. It has been our privilege to spend some time with Mr.
James E. Howard, the operator, and to witness some very important tests which were
made on boiler plate and riveted joints. We believe that these tests, when published,
will have a very important bearing on boiler construction. We regret that they cannot
be published as they are made. The deep interest which Col. Laidley and his assistants
have taken in these experiments is worthy of all commendation, and engineers will find
in the reports when published much valuable information that cannot be gained from
any other source. If any plan can be adopted by which engineers can be put in posses-
sion of the results as they are made, it would be a great improvement. But we doubt if
men could be found who would show more interest in the work than those now in charge.

Through the courtesy of the editors of the Industrial World, we are able to reprint
the following interesting article which appeared in a late issue of their paper.

The First Locomotive Engine.

The accompanying engraving is a correct representation of the first engine ever
employed on a railroad, and is copied from a photograph taken by Mr. Peter Rhodes, of
Darlington, England. The engine itself is now to be seen standing opposite the depot
building in that city. It was built by George Stephenson, the celebrated engineer, in

The First Locomotive Engine.
1825, and is the identical engine that pulled the first train of passenger coaches ever
drawn by steam, a mention of which was made by a correspondent of the Industrial
World, of November 24, 1881. This engine was in continuous service on the Darlington
& Stockton railway, from 1825 to 1858, when it was relieved from duty, and has since
been on exhibition, as above stated.

It may be imagined, from the peculiar construction of the working gear of this

40 THE LOCOMOTIVE. [March,

engine, with its upright cjiinders, massive cross-beams, and long connecting rods, that
it was a cumbersome affair and, being painted black, it had an awe inspiring appearance.

The wooden tender had a box on top of the water tank, into which, at each depot,
a supply of coal was passed out of the freight car, sufficient to run the engine to the
next station.

The first style of brake ever used on railroads is also shown in the illustration. It
consisted simply of a huge block of hard wood fixed on an iron pin, and having attached
to it an iron lever. When applied, the brakeman placed the weight of his body upon
the upper end of the lever, thus pressing the block of wood against the face of the two
wheels. Placed side by side with the elegantly perfected locomotive of the present day,
this engine, tender and freight car are quite suggestive of the marvelous progress made
in railroading machinery, within the memory of men still living, inasmuch as the fore-
going facts were furnished to us by a person residing in Iowa, who saw this engine make
its first trip. We may further remark in this connection, that there were three persons
whc shared the honor of constructing and operating the Stockton & Darlington railway.
One was George Stephenson, whose action in this regard we have already referred to,
and who^e subsequent history is known to the world. Another was Hon. Edward
Pease, of Darlington, who is entitled to the honor of having been the first treasurer of
any public railroad corporation. Mr. Pease was a highly esteemed and wealthy Quaker,
and, being elected a member of Parliament, was the first of his denomination allowed to
be enrolled as a member of that body without taking the usual oath of office. The
other person was Richard Otley, Esq., who may be truthfully claimed as the first chief
executive official connected with any railway corporation. In addition to being the
secretary of the company, Mr. Otley was superintendent, manager, director and engineer.
His son, J. W. Otley, Esq., now resides at Perry, Iowa, and, like his father, is dis-
tinguished as a railroad engineer and surveyor, having practiced his profession for about
twenty-five years, a portion of the time as chief engineer of the old Des Moines
Valley railroad, from Keokuk to Fort Dodge. Mr. Otley made a visit to Darlington a
few years ago, and, on his return to the United States, brought with him the photograph
from which our engraving is copied.

Boiler Explosions in England in 1881.

At the last monthly meeting of the Executive Committee of the Manchester Steam
Users' Association, on Friday, February 3d, Mr. Lavington E. Fletcher, Chief Engineer,
presented his report, from which we learn that during the past year 12,138 boiler
examinations had been made. No explosion had arisen from any of the boilers under
the inspection of the Association during the year, but tM'enty-five explosions had occurred
throughout the country outside of its ranks, killing 35 persons, and injuring 40 others.
These explosions had all arisen from simple causes repeatedly met with, and the greater
number, at all events, might have been prevented by competent independent inspection.

Nine explosions, killing 21 persons and injuring 25 others, arose from the defective
condition of the boilers; in one case accompanied with excessive pressure.

Seven, killing 4 persons and injuring 13 others, arose from malconstruction, coupled
in three cases with defective condition, and in another, with caulking under steam
pressure.

Five, killing 4 persons, and injuring 3 othei's, arose from excessive pressure.

Three, killing six persons, arose from overheating through shortness of water. As
to the remaining one, no particulars had been obtained.

In addition to tliese twenty-five steam-boiler explosions, forty- one explosions, kill-

1882.] THE LOCOMOTIVE. 41

ing 8 persons, and injuring 11 others, had arisen from kitchen-boilers during the frost
at the beginning of the past year. These explosions were due to an accumulation of
pressure caused by the choking of the outlets with ice, and might have been prevented
by the adoption of a small reliable safety-valve.

The report attributed the recent locomotive boiler explosion on the Northeastern
Railway at Stockton, by which five persons were killed, to overheating of the furnace-
crown through shortness of water. The boiler was lifted from the ground, turned
bottom upwards, and thrown on to a truck in a goods-train standing in advance. The
Association had recorded sixty-six locomotive boiler explosions since the year 1861, a
large proportion of which arose from internal grooving at the longitudinal seams of
rivets in the barrel. This source of danger, however, was now guarded against by more
frequent internal examinations, and in many cases by the adoption of double butt-strips
at these seams, one inside, and the other out, the object of wliich was to prevent the
buckling action which gave rise to internal grooving. An internal examination of a
locomotive boiler involved taking out the tubes, but this it was thought was an expense
that ought to be faced in the interest of the public safety, at least once every three years.

The average working results of 33 economizers, or feed-water heaters under inspec-
tion were as follows: Temperature of gases on entering the economizer, 584 degrees;
on leaving, 393 degrees; fall, 193 degrees. Temperature of the feed on entering the
economizer, 95 degrees; on leaving, 317 degrees; rise, 133 degrees.

The Manchester Steam Users' Association is promoting a bill in Parliament for the
prevention of steam boiler explosions, the scope of the measure being to provide a more
searching investigation of boiler explosions than that at present made by the Coroner's
court, and also to secure such an investigation, whether the explosion be fatal or not. —
Bngineering.

The Cause of Boiler Explosions.

Gas caused by the decomposition of water and ignorance in the person using the

boiler at the time of the explosion. There is not a particle of steam in the boiler, and

it does not matter as to the amount of pressure in the boiler whether it is one pound or

100 pounds to the square inch, if it takes fire it must go. It does not matter whether

the boiler is new or old, weak or strong, or how many safety-valves there are on it, or

where the water is, gas is liable to occur at all stages of water — more liable when the

water is low. Now, what is wanted to prevent boilers from exploding is for all men

firing under boilers to know when gas occurs, and what to do. A sickish sweet smell,

and the absence of steam is a sure indication of gas. Wet out your fire immediately,

and let the fire door be open. Let on a full supply of water. No steam will evaporate

as long as gas has the ascendency. If there is any wood-work near the safety-valve, do

not let oflF the gas, or it will fire the wood. The price of safety is eternal vigilance.

Nine-tenths of all the explosions may be prevented by the proper information being

acquired by persons using steam boilers. The Portland explosion was gas and

ignorance combined.

Jas. Carpentek, Fo7'ti/ years an engineer.

The above is copied verhatim from the Louisville Courier-Journal, and taken alto-
gether is about as laughable a piece of nonsense as we have seen for some time. The
ideas advanced completely destroy all chance of safety in the use of steam. We infer
from his opening statement, that explosions arise from "gas caused by the decomi^osition
of water and ignorance " in the fireman. We must confess to our utter ignorance of
the nature and properties of gas generated by "the decomposition of water and igno-
rance," but presume it must be something terrible. Some of our chemists should study
this wonderful chemical compound, and enlighten an anxious community on the subject.

42 THE LOCOMOTIVE. [March,

Now it is evident to the ordinary unbiased observer, that the persons of all firemen
are either liable to be afflicted by gas caused by the " decomposition of water and igno-
rance" or else they are not \i&h\e to be so afflicted. This we hold to be self-evident.
Now in his first sentence he says explosions are caused by the decomposition of water
and ignorance, and in his last paragraph he says, the Portland explosion was gas and
ignorance combined. Now if the decomposition, or combination of these strange chemical
substances arc equally dangerous and destructive, what are we poor mortals to do?
Every avenue leading to safety seems to be completely closed. We confess our inability
to see any very close connection between any gas which may be generated in the person
using the boiler, and the safety of the boiler, but then we haven't been " Forty years an
engineer," and don't claim to know everything. Perhaps we will grow wiser as we
grow older. At any rate we don't propose to allow any more firemen to have anything
to do with water in any form. This will prevent any further trouble from that source,
at all events.

But we must forbear to comment further, as we feel that any efforts we can make to
say funny things, will be completely overshadowed by the sublime humor displayed by
tlie article in question.

Webb's Compound Locomotive.

To Mr. Webb, locomotive superintendent of the London & Northwestern railway,
is due the credit of being the first English engineer who has in recent years produced a
startling novelty in locomotive engines. In France, Belgium, and Austria remarkable
specimens of locomotive construction are turned out every now and then ; and America
has recently come to the front with the Fontaine locomotive. But in England we have
preferred to follow the even tenor of our way simplifying details, adopting better
methods of putting work together, and rendering engines more substantial and more
serviceable, refraining from making excursions into unknown regions of invention ; and
it can hardly be disputed that the result of this policy has been on the whole satisfac-
tory. This, however, is no reason why departures should not be made now and then
from the beaten path of locomotive construction, and to condemn Mr. Webb's design
hastily or without due thought would be rather worse than foolish. For the present
Mr. Webb is reticent about the engine, and naturally so. It will be time enough to
bring it prominently before the world when it has done some work. It will then form
the subject, no doubt, of a paper to be read before the Institution of Mechanical En-
gineers. Meanwhile, we can at least satisfy the curiosity of our readers concerning its
prominent peculiarities, though we can do little more.

The new engine has been constructed at Crewe, and is similar as regards boiler,
wheels and so on, to the four-coupled express engines of the London & Northwestern
railway, with which all English engineers, at least, are tolerably familiar. The trailing-
drivers are driven by a pair of outside cylinders, 11^-inch diameter and 24-inch stroke,
secured to the side frames at a point just in advance of the leading driving-wheels.
The piston-rod heads are guided by two flat bars, one at each side, instead of four, as
usually employed, the crosshead being channelled to slide on the bars. The slide valves
are worked by Joy's patent gear, and the connecting rods lay hold of pins in the wheel-
bosses. So far we have a complete engine with outside cylinders and a pair of driving-
wheels behind the fire-box, the whole closely resembling Crampton's patent engines, of
happy memory. la the smoke-box, right beneath the funnel, is fixed a third cylinder,
26-inch diameter and 24-inch stroke, the connecting rod of which lays hold of the pin
of a single crank in the middle of the length of the leading driving-axle. The exhaust
steam from the two small cylinders passes into a kind of gridiron of pipes between the

1882.] THE LOCOMOTIVE. 43

engine frames, which pipes act as an intermediate receiver, and from thence it is led into
a copper pipe coiled in the smoke-box, in order that it may be reheated and dried.
Thence it goes into the valve-chest of the large cylinder. We have thus a locomotive
with a single pair of driving-wheels in advance of the fire-box, driven by a single cyl-
inder. . It must be understood that the Crampton engine and this single cylinder
engine are quite independent of each other — that is to say, each may run at any
pace it can. There are no coupling-rods, nor is there anything to maintain a fixed rela-
tive position between the cranks of the single and double cylinder engines, save the rails.
The single engine depends for its supply of steam on the double cylinder engine, and
should the latter slip, more steam is sent into the receiver than the large cylinder will
take, and the back pressure rises, and so tends to check slipping; while for the same
reason the pressure on the large piston is augmented, and it may slip its wheels. If, on
the contrary, the single engine slips first, it will take more steam away than the other
engines can supply, and its own pressure will fall off while the efi'ective pressure in the
other cylinders will be augmented. It is found that this controlling action operates
very effectually, each engine doing its own share of the work fairly. No inconvenience
results from the changing position relations of the crank-pin, the size of the intermediate
receiver being sufficient to prevent irregularities in the amount of back pressure of much
moment. With a boiler pressure of 120 pounds the pressure in the receiver averages
about 50 pounds. Such, then, briefly stated, is Mr. Webb's compound locomotive. It is
a handsome engine, and has been run at very high speed with perfect steadiness.

Mr. Webb has not, we need hardly say, adopted so abnormal a design for a whim.
On the contrary, he expects to derive important advantages from this system of con-
struction; and it is not too much to say that of the many compound locomotives which
have been proposed and patented, this is immeasurably the best. He claims, in the first
place, that he gets all the advantages of a coupled engine without its disadvantages.
Now, practically, the advantages and disadvantages of coupled and uncoupled engines
resolve themselves into a question of coal bills. Mr. Stirling has stated that a coupled
engine will burn from 1 pound to 2^ pounds of coal more per mile than an uncoupled
engine ; but other locomotive superintendents say that on the whole the advantage is
with the conpled engines, because they do not slip, and nothing wastes fuel more than
slipping, which tears a fire to pieces, besides throwing away steam. In lieu of two
coupling rods, with such frictional resistance as they set up, Mr. Webb gets an extra
complete engine. It can hardly be possible that the frictional resistance of all kinds
caused by coupling an engine can be as great as the resistance of a piston, valve-gear,
cross-head and connecting rod. Secondly, Mr. Webb claims that by working his steam
through two engines in succession, he will get great economy of fuel. On this point,
also, there is much room for doubt. The first cost of the locomotive is, of course, in
excess of that of a locomotive of the same power of the ordinary type; and there are
three engines to be kept in repair and lubricated instead of two. These points must not be
overlooked. Now, the objections to sending an engine into the shops for rejiairs are so
great that all locomotive superintendents are straining every nerve to get the largest
possible mileage out of their stock; so that there is reason to conclude that there must
be not only a saving in fuel, but a very substantial saving effected by Mr. Webb's engine,
before it can be regarded as a success. The locomotive has already done a good deal of
hard work in, we understand, a most satisfactory manner, and so far as can be ascer-
tained, there is reason to anticipate that a saving of fuel will be effected; how great no
one at present knows. Mr. Webb is very well satisfied with the results he has obtained
80 far. The experiment will be watched with interest by railway engineers all over the
world, and we wish Mr. Webb that success which his skill and inventive talent deserve.
— The Engineer.

44 THE LOCOMOTIVE. [March,

How Long may a Boiler be Used?

There lias been considerable discussion lately concerning the life of a sieam boiler
in active service. Some very remarkable statements have been made, and many absurd
reasons advanced for the purpose of making the public believe that after a boiler has
been used just ten years, it suddenly becomes dangerous and unfit for further use;

It is an unfortunate fact, that more nonsense has probably been written on the
subject of steam and steam boilers, than any other one thing in the vrorld. A great part
of this nonsense emanates from those who are interested in the manufacture and sale of
patented humbugs; this class of people generally have little or no knowledge of what
they are talking about, and no regard whatever for the interests of the steam-users for
whom they profess so much solicitude.

There is no more reason why a steam boiler should be condemned at the end of ten
years' service, than there is for condemning any other engineering structure at the end of
that time. A steam boiler, properly made of good materials, and used with proper care,
will run for twenty-five years with perfect safety and economy; on ihe other hand, the
same boiler may be utterly ruined or blown up, inside of twenty-five hours from the time it
is first fired up.

A great deal has been said and written about iron losing its strength and becoming
crystallized through long use. Cases have occurred where this has appjirently been the
result of long usage in steam boilers, but if all the facts were known, it would probably
transpire that the iron was originally defective, or had been repeatedly overheated. For
there is abundant j^roof that long service, per se, does not render good iron brittle. The
writer knows of a case where the plates of a boiler taken out a few months ago, after
twenty-six years of active service, showed no deterioration of quality whatever, and
incontestible proof of tJiat is furnished in the fact that the shell-plates were flanged and
put into the heads of other boilers, and they stood the test of flanging in the most sat-
isfactory manner. Surely if ten years' service is sufficient to ruin good iron, these shell-
plates would not have stood the test of flanging after nearly three times that length
of active service.

But the falsity of the position taken by these people who advocate the "ten years'
service hit or miss rule," is shown by the fact that no two of them advocate it for the
same reason. The originator of the idea based his reasons for it, on the alleged deteriora-
tion of iron through long usage. Another later advocate of the same thing, who seems to
have no very clear idea of what he is writing about, advocates it because, " Avhen a boiler has
been used long enough to need patching, then it is time to throw it into the scrap-heap."
His remarks seem intended to convey the notion that when a boiler is just ten years old,
it must of necessity be patched. He seems to be totally oblivious of the fact that most
patches are put on for entirely different reasons than the one he gives, viz., '' when a
boiler needs patching, it has been worn down thin." He ought to go out among boilers
awhile, and see what is going on, and then, perhaps, he wouldn't display such utter
ignorance of his subject.

Looked at in any light, the idea that boilers should be limited by law to ten years'
service, is a most pernicious one. The practical working of such a law would have
precisely the opposite effect to that intended. Boiler owners, knowing that the use of their
boilers was limited to a certain invariable term, would strive, and justly too, to get all the
work out of them that they could in the allotted time. The natural consequence would be,
to force the boilers beyond their limit, they would not be so particular in regard to their
care as they are now, and the inevitable result would be a great increase in the number
of explosions. We think any one who denies the force of this reasoning, would be con-
vinced of its truth after a short practical experience under the working of such a law as
that proposed. h.

1882.] THE LOCOMOTIVE. 45

There are steam boilers under the care of this company which have been in continu-
ous service for upward3 of eighteen years, tliat are as perfect now as they were tlie day
they were put in. Clean, free from scale or sediment, leaks have never occurred, frac-
tures, grooving and corrosion are unknown, and they are apparently good for years
more of service. On the other hand, new boilers of the best material and workmanship,
have been totally ruined and condemned inside of a year from the day they were first
fired up. What would have been the practical working of the ten year rule in such
cases as these? In the first, it would have been downright robbery of the owners of the
boilers; in the second, it would have been simply the death warrant of any person,
who, by an unfortunate chance happened to be within range of the flying fragments
when the final catastrophe occurred. H. F. S.

Distance apart of the Supporting Lugs on Boilers.

As there seems to be a wide difl'erence of opinion and practice regarding the proper
distance apart of the supporting lugs of steam boilers, perhaps a few words in regard to
the matter may not be out of place here.

There is a wide diversity of practice among the different boiler makers on this point,
some never putting more than two sets of lugs on all the ordinary proportions of boilers,
and others almost invariably putting on three sets. Let us examine the matter briefly,
and see if we can arrive at any definite conclusion.

It is evident that an ordinary steam boiler, filled with water and supported by lugs
resting on the walls on either side, is in the condition of a beam of an annular cross-
section, with the load uniformly distributed. The general formula for the breaking
weight of such a beam is as follows:

^ , . . , 3.1416 X square of diameter X thickness X tensile strength,

Breakmg weight = H — -r—. — ; — \ t-— z

° ^ length in inches between supports.

when the load is concentrated at the center; when the load is uniformly distributed it
will sustain just ticice as much.

Let us take for example a boiler 60" diameter, 15 feet long, shell ^Y' thick, 66 three-
inch tubes with supports 13 feet apart. Then by the above formula, the uniformly dis-
tributed load required to produce failure, would be 2,236,528 pounds. This result wc
must reduce about four-fifths to allow for the diminished section of the shell at the girth-
seams, and this result about one-tenth more to allow for the straining action due to the
steam pressure on the heads; this leaves us in round numbers, 1,200,000 pounds as the
breaking weight, which divided by a safety factor which should not be less than 10,
gives us 120,000 pounds, which may be safely distributed upon the boiler-shell.

The weight of that portion of the boiler-shell between the supporting-lugs would be
about 2,500 pounds, and of the water contained therein, about 7,500 pounds. This gives
10,000 pounds as the weight distributed through the boiler, which we have just seen is
capable of safely sustaining about 120,000. This shows that for the ordinary sizes and
proportions of boilers, two sets of supporting lugs are amply suflicient. This view is
also borne out by the behavior of such boilers in daily use, as they never give out by
" breaking their backs," as it is called.

With the smaller sizes however, especially when they are of great length, we must
deal cautiously. Let us suppose we have a plain cylinder boiler, 36" in diameter, and 33
feet long, shell ^" thick, supports 25 feet apart. We shall find in this case by the same
process as above, that 8,000 would be the limit of the load, while the weight of the boiler
and its contained water, would be about 10,000 pounds as before. In this case our factor

46 THE LOCOMOTIVE. [March.

of safety would be reduced to eight, which is not sufficient, as is shown by the fact that
many iron work boilers of substantially the above proportions, have exploded disas-
trously by rupturing at their girth-seams.

In the above examples we have neglected the influence of that portion of the boiler-
shell which overhangs the supports at each end, not only for the purpose of simplifying
the calculation, but because in many cases the supports are placed so near the ends of
the shell that it does not materiallj- influence the strains between the supports. In many
cases, however, this might be taken advantage of, by riveting on the lugs at such a dis-
tance from the ends of the shell, that the strain produced on the top of the shell by th«
weight of the overhanging part, shall be equal to that on the bottom of the shell by the
weight between the supports; by this means, the straining action would be reduced to a
minimum, and to a great extent equalized. In many instances this arrangement would
undoubtedly be preferable to three sets of lugs, especially where there is no provision
made for the middle lug to adjust itself to the varying position of the central portion of
the boiler, due to expansion of the under shell of the boiler.

A good "rule of thumb" for placing lugs on boilers is to put them not over 4 diame-
ters apart. Thus in the case of the 60-inch boiler in tiie first example, two sets of lugs
will be found sufficient, unless the boiler is above 20 feet long; while in the case of the
36" boiler, a support would be required every 12 feet. Where only two pairs of lugs are
used, a convenient method of locating them will be to divide the distance between the
tube-sheets into six equal parts, and place the lugs each one of the parts from the
tube-sheet. Thus in the case of a boiler 15 feet between heads, place the center of the
rear supports 2^ feet from the end of the boiler, and the center of those at the front end,
2^ feet back of the front tube-sheet. By this means the strains are very evenly dis-
tributed. H. F. S.

At the late fair of the Massachusetts Charitable Mechanic Association, at Boston,
examples were shown of tests of materials made by the machine lately erected in the
United States Government Arsenal, at Watertown, for the proving of structures of full
working dimensions. A steel wire cable. If inches in diaraeter, was shown, which had
withstood a pull of 75 tons, when the fastenings by which it was held gave way,
although the cable itself remained sound. A hammered iron bar 6 inches in diamete*-,
was shown to have concealed a crystalline formation of the fibres, and it consequently
parted with a loud report under a strain of nearly 723,000 pounds, or 36,900 pounds to
the square inch. A smaller wrought-iron bar drew down and broke with a fibrous
structure under a pull of 51,240 pounds per square inch. Some pine wood columns were
also shown which had been tested by compression. The first of these, originally 12 feet
long, yielded at a pressure much below its estimated strength, in consequence of a large
knot in the side which acted as a comparatively incompressible wedge. Another column
was a spar 12 feet long, 75-inch butt, and a 6|-inch top. This stick was a perfect sam-
ple, and gave way by splintering at its smaller end. A seasoned hard pine girder, 11
inches square and 10 feet long, bore a load of 751,000 pounds.

We are indebted to The Insurance World^ of Pittsburgh, Pa., for a very neat and
comprehensive Fire Insurance Chart. It has the statistics showing the standing of the
principal companies doing business in the country, also a list of those which have retired
from the field in the past five years. The chart is valuable to insurers. Send for a copy.

1882] THE LOCOMOTIVE. 47

Avoid Waste.

Every man in a workshop ought to constitute himself the guardian of his em-
plojTer's property, and not only should he avoid waste himself, but as far as practicable
he should discourage it in others. If this were done, millions of dollars would be saved
to the country, a much larger percentage of profits would go into the pockets of the
employer, manufacturers would be enriched, and, in the end, tlie workmen would be
proportionately benefited. Strange that these simple facts should have so simple weight,
but so it is. Waste by another is cruel to the man who has to pay; it does not, cannot
benefit the person guilty of it, and it is a dead loss to the nation ; and every scrap of
material so destroyed makes the product more costly, and consequently dearer. In the
interest of workmen it is important that these facts should be borne in mind. "Wages
bear a relative proportion to cost of raw materials, and both combined determine the
price of commodities; the cheapness of the latter augments their sale, increases their
production, enhances the demand for labor, and tends to keep up wages; the reverse is
wholly true. If, therefore, an obvious duty is neglected or carelessly performed, the men
mainly responsible ultimately suffer, and that suflering will be in an exact ratio to that
which produced it.

One great remedy for the losses incurred by waste is a closer supervision of every
detail of the undertaking, whatever it may be. This, however, involves extra expense.
If the men can contribute to a saving, in this respect, they will indirectly reap the
advantage. To oveilook this fact shows a lamentable ignorance of the internal economy
of a workshop, and of the forces and influences always at work for the purpose of bring-
ing about a given result. The men who complain of strict supervision are just those
who need it most, and who, without it, would render large contracts next to impossible,
for the simple reason that they would not pay, and therefore could not be executed.
Many a builder and contractor has been ruined by the wastefulness of his employees
and negligence of his foreman. A careful man is a jewel in a workshop. — Builder and
Woodworker.

Noises ix Ste.4.m Pipes. — The primary cause of the loud hammering noises that
are often so annoying to occupants of apartments heated by steam pipes, is the conden-
sation of steam in the system of pipes. When the steam is first turned on, it takes some
time for the pipes to become thoroughly heated, and the steam in contact with the cold
metallic surfaces condenses. This water of condensation is further cooled oft' by contact
•with the metal and in turn condenses the steam immediately in its vicinity, with more or
less suddenness. The pressure being thus removed from one side of the water column,
the body of water is driven by the elastic force of the air behind it, violently into the
space occupied by the condensed steam, and, striking against the bends of the coil or
the valves, it causes the cracking or hammering noise referred to. The water body is
again driven forward by the steam, and it again condenses it, and the knocking is re-
peated, the blows often succeeding each other with great rapidity. Or some of the steam
after admission may become shut off" by the condensation between the two bodies of
water, and the noise will then be caused by the violent impact of the two bodies of
water rushing together to fill the vacuum. The familiar experiment of the "water
hammer" will explain how, in the absence of any resisting body like the air or other
elastic body, a mass of water will strike a resisting surface with all the effect of a solid
body. On account of the inconvenience experienced from this cause, provision is always
sought to be made in steam heating apparatus to provide for drawing off the water of
condensation in traps, thus removing it from the pipes and coils as rapidly as it accumu-
lates. When the steam is shut oflF, the condensation of the residual steam in the pipes
and coils may produce the same hammering noise, though to a less degree than imme-
diately after its admission. — Milling World.

THE LOCOMOTIVE.

[March,

Incorporated
1866.

Charter Per-
petual.

Issues Policies of Insurance after a Careful Inspection of tlie Boilers,

COVERING ALL LOSS OR DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

AEISINQ FROM

Steam Boiler Explosions,

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full information concerning the plan of the Company's operations can be obtained at the

Or at any Agency.

J. M. ALLEN. Prest. W. B. FRANKLIN, Vice-Prest. J. B. PIEECE, Sec'7.

Soard of Directors :

J. M. ALLEN. Preeldent.

LUCIUS J. HENDEE, Preat. Mtn& Fire Ins. Co.

PRANK W. CHENEY, Trcae. Cheney Brothers Silk

Manufacturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Amer. Nat. Bank.
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Manufacturine Co.
THOMAS O. ENDER8, of ^tna Life Ins. Co.
LEVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Hon. HENRY C. ROBINSON, Attorney at Law.

Gen. WM. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire

Arms Mfg. Co.
GEO. CROMPTON, Crompton Loom Works, Wop-

Hon. THOS. TALBOT, Ex-Qovernor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manufacturer, Provi-
dence, R. I.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. PARRY, of Baldwin Locomotive Works ,
Philadelphia.

GENERAL AGENTS. CHIEF INSPECTORS.

OFFICES.

THEO H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKIM,
W. S. CHAMBERLIN,
J. L. SMITH,
H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

R. K. McMURRAY,
WM. G. PIKE,
JOSEPH CRAGG,
WM U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN.
J. H. RANDALL,
A. C. GETCHELl.,
J. S. WILSON,

New York City.
Philadelphia.
Baltimore.
Boston, Mass.
Providence, R. I.
Chicago, III.
St. Louis, Mo.
Hartford.
Bridgeport.
Cleveland.

CiNOINNATX.

OflBce, 285 Broadway.

" 430 Walnut St.
" 10 So. Holliday St.
" 10 Pemberton Sq're.
" 15 Weybosset St.

" 182 La Salle St.

" 404 Market St.

" 218 Main St.

" 328 Main St.

" 246 Superior St.
" 53 West Third Si.

Ife

0r0m0fet

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series— Vol. III. HARTFORD, CONN., APRIL, 1882.

No. 4.

Report of the Experiments on Boiler Explosions.

MADE BY MR. D. T. LAWSON, AT MUNHALL FARM, NEAR PITTSBURG, PA.

The test made in Februaiy last, "was a failure. The following are the details of the
next attempt, March 7, 1882:

The boiler used was of the plain cylinder type, 5' 9" long, 2' 6" diam., shell -^^" thick,
single riveted ; iron branded 56,000 T. S., heads f " thick, stayed with one rod running
through from head to head, with nuts outside screwed against each head. Height of
water at beginning of experiment was 14", leaving 16" for steam space. The steam guages
used were made by Wm. Kirkup & Sou, of Cincinnati, Ohio.

The object of the experiments was to demonstrate the truth of the theory held by
Mr. Lawson that boiler explosions are caused by the opening of a valve, whereby the
steam escapes, and the highly heated water remaining in the boiler thus relieved from
pressure, suddenly flashes into steam, producing a concussion great enough to explode
the boiler. The following table shows the results attained :

THE LOCOMOTIVE.

[April,

Time of

Steam

The

And rose

Time of

Steam

The

And rose

opening the
valve.

pressure.

pressure
fell.

afterward.

opening
the valve.

pressure.

fell.

afterward.

12-00 M.

100

12-38

180

12-20 P.M.

115

12-39^

190

12-28

1.30

12-41

195

12-31

150

12-42^

200

12-34

155

12-44

205

12-35

160

12-461

210

12-36

170

12-51

215

12-37

175

At this point the front head of the boiler gave out and operations were suspended
until it could be repaired. At 4.41 p.m. the experiments began again.

Time of

Steam

The

And rose

Time of

Steam

The

And rose

opening the
valve.

pressure.

pressure
fell.

afterward.

opening
the valve.

pressure.

pressure
fell.

afterward.

4-41 P.M.

5-24 P.M.

215

4-42

Leaking so

badly that

steam be-

gins to fall.

4-44

• 80

5-26

220

4-48.

5-27

215

4-49

5-28

210

4-52

100

5-29

205

4-54

110

5-30

195

4-56

120

5-31

180

5-00

150

5-32

175

2 .

5- 3

165

5-33

165

5- 6

175

5-34

155

5- 8

185

5-35

150

5-14

200

5-36

145

5-18

210

5-37

140

At this point the boiler leaked so badly that the experiments were stopped. On ex-
amination it was found that Mr. Lawson had been a victim of the drift-pin ; the hole in the
front head for stay-bolt being drilled too small, the boiler-maker had drifted the hole and
fractured the sheet in three places, and when the pressure was up to 220 pounds, the
shock the boiler received caused the fractures to extend, so that operations were sus-
pened until the head could be repaired, which was done by bolting on a piece of boiler
plate, over and around the hole. Thus ended the first day's experiments.

Second trial, March 8, 1882.

Time of

opening the

valve.

Steam
pressure.

The

pressure

fell.

And rose
afterward.

5-41^ P.M.
5-59^

100
125

5
12

5
5

1882.]

THE LOCOMOTIVE.

At three minutes past six the steam pressure had fallen to 120 pounds and the
experiments were stopped. This was caused by leakage around the tap bolts that were
used to fasten the patch to front head. It now began to look as though it would be
with Mr. Lawson as it was with the Government experts when they tried to explode new
boilers, and only succeeded in straining them so that they leaked so badly that the leaks
became safety-valves.

The third trial, March 10, 1883.

At 11.35 A.ir. the steam-gauge registered ten pounds. The pressure gradually
increased to 175 pounds at 12.04 p.m. when upon attempting to open the valve it was
found to be stuck, and as no one dared to approach the boiler to open it, everyone
remained in the bomb-proof and awaited the result. At 12.13 the pressure had reached
275 pounds, when the boiler sprung a leak and the pressure began to fall. It was then
decided to abandon that boiler and experiment with the one which was provided with
Mr. Lawson's Patent Diaphragm, which is simply a perforated plate running from end to
end of the boiler above the water-line.

The fourth trial, March 20, 1882.

Boiler provided with Lawson's Patent Diaphragm.

At the trial of this boiler in February last it was not exploded.

tt>

Ganfje in steam

Gauge below

Gauge in Ptoam

' Gaug-e below

above

plate.

above plate.

plate.

o'S

■ga

Down.

Up.

Down.

Up.

E£

Down.

Up.

Down.

Up.

E-

£->

<J2

12-50^ P.M.

1-15

175

12-59

1-2U

200

1- H

100

l-29f

225

1-8^

125

1-38

230

1-11^

150

At this point the steam went up so slowly that the experiments were interrupted to
build a fresli fire.

Sfl

Gange in steam

Gauge below

4^*

Gauge in steam

Gauge below

w >

above plate.

plate.

above plate.

plate.

"Tra

'i:'^

c >

O 3J

.= 5

Down.

Up.

Down.

Up.

.= -

Down,

Up.

Down,

Up.

2-43 P.M.

225

2-49f

275

2-46^

250

2-57^

300

After reaching 300 pounds as above it was concluded to stop this trial, remove the
diaphragm, and try this boiler without it. On cooling down the boiler was found in
good condition, every seam being tight and showing no signs of having been strained.

The fifth trial, March 22, 1882.

Boiler with diaphragm removed.

THE LOCOMOTIVE.

[April,

£f

Upper

Lower

Upper

Lower

gauge.

■^■3

c >

O 0)

o o

Down.

Up.

Down.

Up.

S —

Down. Up.

Down.

Up.

I»

2-10 P.M.

2-31 f

100

2-15?

2-35f

125

2-20f

2-38

150

2-26

2-41

175

At this point the steam was blown down to allow the brickwork to dry, the boiler
having been re-set ; and to replenish the fire.

1 W)

•a

Upper

Lower

1 '=

Upper

Lower

8) .
O >

gauge.

^" :3

^■3

C %

0 0

.= =

Down.

Up.

Down.

Up.

.§5

Down.

Up.

Down.

Up.

c»

3-2

175

3-7f

225

3-4

200

3-8

235

3-5 1

210

At 235 pounds pressure as the valve was opened the boiler violently exploded. The
main portion of the shell was thrown a distance of about 1,000 feet, with such force as to
cut off the tops of several trees that were in its course.

The sketches on first page show the appearance of the principal fragments into which
the boiler was torn. No. 1, is the shell. No. 2, a smaller piece of the shell. No. 3, the
front head, and No, 4, the back head in which the manhole was placed ; this piece landed
on top of the bomb-proof where the observers were posted.

Capt. Fehrenbatch, Supervising Inspector for the Seventh District, and Messrs. Atkin-
son and Batchellor, Local Inspectors for the government, located at Pittsburg, assisted
per order of the government, and Mr. A. C. Getchell, Chief Inspector for the Cleveland,
Ohio, Department, represented the Hartford Steam Boiler Inspection and Insurance Com-
pany.

Pieces of shell were tested after the explosion by Capt. Fehrenbatch, on a Riehle
testing machine, and found to have a tensile strength of 61,449 pounds per square inch,
which is remarkably strong for iron boiler plate. From the foregoing results it is prob-
able that many destructive boiler explosions maybe averted by the use of Mr. Lawson's
apparatus, still it is evident that it cannot influence the effects of varying expansion, crys-
tallization, corrosion, and other kindred defects, and that boilers must still be very care-
fully watched and often inspected.

A. C. Getchell, Inspector.

1883.]

THE LOCOMOTIVE.

Inspectors' Reports.

February, 1882.

Below is given the summary of the inspectors' reports for the month of February last
From it we lelrn that the number of visits made was 1,681 ; the tota -mber of bo^le
examined was 3,685; the total number inspected internally was 1,401; the number
tested bv hydraulic pressure was 349 ; and the-number condemned was 33.

Th Jwhole number of defects reported was 1,464, of whicl. number 391 -.-e con-
sidered of so serious a nature as to impair the safety of the boiler. A list of the defects
in detail follows : —

Nature of defects.
Cases of deposit of sediment.
Cases of incrustation and scale,
Cases of internal grooving, -
Cases of internal corrosion, -
Cases of external corrosion, -
Broken and loose braces and stays,
Settings defective.
Furnaces out of shape.
Fractured plates,
Burned plates.
Blistered plates.
Defective rivets.
Defective heads,
Serious leakage at seams.
Serious leakage around tubes,
"Water-gauges defective,
Blow-out defective, -
Cases of deficiency of water,
Safety-valves overloaded.
Pressure gauges defective.
Boilers without pressure gauges.

Whole number. Dangerous.

Total,

208
300
11
68
101
33
6
77
141
76
191
2
3
1
6
25
22
7
37
141
8

1,464

43
41
6
15
35
21
0
17
81
39
29
0
0
0
0
0
11
5
12
30
1

391

The question of the relative value and efficiency of the hydrostatic and l-™-er te
has been again brought to the notice of the general public, through the medium of the
da ly press, which has freely discussed the circumstances of the late explosion at Jewel l.s
Zl in Brooklyn, N. Y. As many of the ideas which have been advanced ui regaid to
^t subject are ^-ell calculated to mislead the general reader, we will endeavor to pre-

sent the subject in its true light. t „^ ;.. whnt i<! fl.p

The first question that naturally arises in a discussion of the subject is: What is the
object of the hydrostatic test? Primarily, to ascertain if the boiler is capable of su -
tlTnVsome given pressure, somewhat in excess of the required working pressure ; if it
dTratLctfrily sustain this pressure, then it is assumed that t^^^^ ^ ^^^
under the conditions of practical use at the working pressure. Secondly, to test the
titrhtnessoftheioints and the quality ofthe work generally. , ww

'The next question that arises is:-What is the pressure which is best calculated to
fulfill the above requirements without injury to the boiler ? In seeking an answei to this
question we obtain some idea of the true value of the hydrostatic test.

54 THE LOCOMOTIVE. [April,

The following are some of the official rules and regulations regarding the testing of
boilers :

The United States laws prescribe that the pressure applied under the hydrostatic
test shall be 1^ times the working pressure. Thus, a boiler to be worked under a steam
pressure of 80 pounds per square inch would be subjected to a hydrostatic pressure of
120 pounds; when the working pressure is to be 90 lbs., the test pressure would be 135
pounds, and so on.

The French laws require a test pressure double that of the working pressure. This
must be applied to merchant vessels at least once a year; in the case of naval vessels, the
boiler when new must be tested to twice the working pressure, and annually afterwards
to one and one-half times the working pressure.

The English Board of Trade rules prescribe a test pressure double the working
])ressure.

Various other authorities recommend a test pressure of from 1^ to 3 times the
working pressure. Thus it will be seen that there is a wide diversity of opinion on the
subject, from which it is fair to infer that its efficiency in some cases may be very
doubtful.

Let us consider the matter briefly. It may be considered to be reasonably well settled
that iron cannot be strained beyond its elastic limit without serious and permanent in-
jury. Also, it may be considered equally well demonstrated that it may be strained nearly
up to its elastic limit without injury. The only doubtful fiictor in the question is the
exact point of the limit of elasticity of any given piece of material. This can only be
determined by actual test of the specimen. The elastic limit o? ordinary iron boiler plate
is about 20,000 pounds per square inch of section. We will apply these facts to a case in
practice.

Suppose we have a boiler 60" in diameter, made of -/g" plate, longitudinal seams
double riveted. And here we would caution one to beware of the average double riv-
eted seam. It is generally supposed to be 20 per cent, stronger than a single riveted
seam, in the same plate; but where the pitch is the same as in the single riveted joint,
as most boiler makers make it, it cannot be materially stronger. We must in every case
reel-on simply on the amount of plate section left hettceen the rivet holes after they are
punched. Suppose, then, that the plates are stamped 4o,00(J T. S. The tensile strength
is not an accurate measure of the elasticity, but with plates marked as above the elastic
limit for practical purposes may be taken at 20,000 pounds. Further, suppose our
double riveted seams have rivets pitched 2" apart from center to center, and that the
rivet holes are ]|" diam. ; this is a very common proportion for this joint. Then the pro-
portion of plate cut away for the rivets is if divided by 2. = .4. This subtracted from
1 leaves us .6 of the area of original plate, which should be taken as the efficiency of the
joint.

Now then, we shall have for a pressure which will strain the material of the shell to

its elastic limit ~ ' ^ "'« ^ T" = 125 pounds per square inch. But we should never

subject a boiler to a strain quite as high as the theoretical elastic limit. We must make
an allowance for unavoidable imperfections in the workmanship, otherwise we would
inevitably strain some part of the boiler a little beyond the limit of elasticity, and thus
do it an injui-y. As we may safely tix the working pressure at one-hr\lf of that due to
the elastic limit, in this example it would be, say, 62^ pounds; then if we applied a test
pressure double the working pre:sure we would very likely seriously injure some por-
tions of the shell. But if we apply only U times the working pressure, we keep within
the safe limit and no harm can possibly be done. So we may conclude that 1^ times the
working pressure is about right for the hydrostatic test; iut, the working pressure

1882.] THE LOCOMOTIVE. 55

should be first calculated from the known strength of the plates and the proportions of
the joint.

Of course the inspector or other person making the above test must satisfy himselt
of the strength of the other parts of the boiler, such as the flat heads, manhole frame,
etc., before applying the test pressure. One thing in particular should he examine, and
that is the joining of the braces to the crow-feet, or angle-iron on all flat surfaces. This
is a part of the structure which is generally made deficient in strength, and should never
be neglected or overlooked.

Having once satisfactorily withstood the hydrostatic test, what benefit is to be de-
rived from repeated applications of it afterward at frequent intervals, when the boiler can
be examined internally ? This is the point on which the dispute in regard to its
efficiency is really based, and we shall refer to it at length in some futurg number.

Plumbago as a Lubricant.

A fly-wheel shaft bearing, eight inches in diameter and ten inches long, carried a
load of nearly ten tous. The bearing was supported on a box-girder, and Avas lined with
good brass. Tl\e engine could not be run as this bearing invariably got nearly red hot
after a few revolutions. Various oils, tallow, sulphur, and gunpowder, were tried with
most indiflferent success. By using a mixture of tallow and sulphur, the engine could be
run half an hour at a time, and once or twice it was run a whole day, the shaft making
sixty revolutions per minute. It was decided to have a new crank, and shaft with a lon-
ger bearing, but, as at the last moment the use of blacl<-lead and tallow was suggested, a
package of the ordinary black-lead used for stoves, was worked up with some tallow, the
bearing carefully wiped, and the grease-box on the cap filled with the mixture. The bear-
ing never heated again unless oil was allowed access to it. The success of tlie plumbago
as a lubricant was perfect. It should be added to the foregoing, that, while the principle
of lubricating by graphite or plumbago is scientifically correct, and has in thousands of
instances been practically illustrated, it has been damaged seriously by the use of impure
graphite. For perfect success the graphite should be perfectly clean. — The Engineer.

A GnosT Story. — About 9 o'clock on Sunday morning a boiler in Atwood & Mc
Cafi'rey's machine shop on Third street, between Market and Ferry streets, exploded
under very peculiar circumstances. The engineer and fireman had been engaged at clean-
ing the boiler and had run all the water out, pulled out all the fire, and taken the
cover of the "man-hole" off", when suddenly the boiler exploded with great force, lifting
the roof of the boiler-shed ofi" its supports and otherwise injuring the sheds. No one was
hurt, but what ia puzzling the firm is what made the boiler explode when it was cold,
empty and the man-hole open. Only one similar case has ever been reported, the latter
having occurred in Akron, Ohio, some time ago.

The above was clipped from a Pittsburg paper. Our inspector, A. C. Getchell, being
in Pittsburg at the time of the accident, called at Atwood & McCaff'rey's to inquire into
the cause. He found that the engineer had blown out the boilers preparatory to clean-
ing, and had put in a quart or more of henzine to start the scale. This mingled with the
air forming an explosive gas. When the engineer opened the mud-drum, to examine its
condition, the gas flowed out, and coming in contact with his lamp or torch was ignited,
causing a violent explosion. We have never before known of benzine being used to remove
scale. Crude pretroleum is sometimes used, mixed with the water to remove sulphate of
lime scale— but never when the boiler is empty.

56 THE LOCOMOTIVE. [April,

HARTFORD, APRIL, 1882.

Mr. D. T. Lawson's Experiments on Boiler Explosions.

The report of Mr. D. T. Lawson's experiment, on exploding boilers at Munhall Farm,
near Pittsburg, will be read with interest. It is fuller in detail than any report which we
have seen published. "We have refrained heretofore from commenting upon these experi-
ments because they had not accomplished all that Mr. Lawson claimed for his theory.
Now that the experiments have been carried out according to programme it is time to
give our opinions.

Mr. Lawson claims, as we understand, that the sudden release of pressure from a
boiler, in quantities sufficient to greatly reduce the pressure for the moment, is liable to,
and probably would, send the boiler in pieces, or in other words, the sudden release of
pressure from a boiler under steam of ordinary, or what may be regarded as safe working
pressure, may produce such a disturbance within as to cause an explosion of the boiler.
This release of pressure may be produced by opening the safety-valve too widely and too
suddenly, or it may result from a slight rupture primarily, in the shell of the boiler.
We have held the opinion for years that a boiler might be injured seriously, if not
exploded, by suddenly releasing the pressure, especially if the usual amount of water was
in the boiler. The most destructive explosions of which we have had knowledge, have
occurred in connection with boilers that have had a full supply of water. An accident
occurred in this vicinity a few years since which confirmed this opinion. A manufac-
turer went into his boiler-room during the dinner hour. The engineer had pumped the
water up to its maximum height, and gone to dinner. He had neglected, however, to
shut the ash-pit doors, which in this case regulated the draft. The fire was burning
brightly and the steam pressure exceeded the point indicated by the weight on the safety-
valve lever. The inference was that the valve was " stuck," but instead of drawing or
deadening the fires with ashes, and closing the drafts, the pr(i{)rietor ran far the j^oker and
threw up the safety-valve lever. The result was a violent commotion within the boiler.
The safety-valve nozzle was instantly torn from the boiler, and together with valve, ball
and lever, carried through the roof of the boiler-house and some distance beyond, across
the highway. A column of steam and water shot up out of the opening, and the boiler
was nearly emptied. It was strained and weakened but there was no rupture save that
caused by tearing off the valve-nozzle. Without entering into a full discussion of the
theory of this accident here, — for we have not the space — we will simply say that the
release of pressure from the surface of highly heated water in a boiler, causes a violent
disturbance in, and rising of the water, and the tendency or flow is violently towards the
point of release. AVhen steam is being raised in a boiler, the water arriving at the proper
temperature steam escapes into a " steam-room." At first the surface of the water is greatly
agitated by the process of ebullition. As the steam pressure increases, the surface of the
water becomes more and more quiet, (it is assumed that no steam is being drawn from
the boiler.) until it is nearly quiescent. From this point the pressure will increase slowly
as shown by Mr. Lawson's experiments. Now suppose the pressure is suddenly released,
the superincumbent steam jiressure becomes so reduced that the contending force whicli
has been held in place by it, (that is the water, highly heated and ready to give up a
large quantity of steam as soon as the superincumbent pressure is reduced,) suddenly
rises with a force corresponding to the differences of i)rcssures, and acts upon the resist-

1882.] THE LOCOMOTIVE. 57

ing metal in the same manner as the enclosed water does upon the end of a glass tube
from which the air has been exhausted. (Referring to the water, however) We say, in
the same manner, we do not intend to be understood as saying that the release of pressure
causes a vacuum. But the differences in pressure would, in our opinion, be sufBcient to
cause the results which usually follow. When we talk about differences of pressure, etc.,
it must be understood that the whole process is almost instantaneous. Had we space we
could explain more fully our reasons for this opinion, which, if we correctly understand
it, is very similar to Mr. Lawson's. The remedy which Mr. Lawson has devised to pre-
vent disasters of this kind, consists of a perforated diaphragm which extends from side
to side and end to end of the boiler just above the water line. It is riveted to tlie sides
and ends of the boiler, and convex on its upper side. To construct a boiler with this
device would require some fine boiler work. And when we consider the defects and dan-
gers to which boilers are liable from unequal expansion and contraction, corrosion and
grooving, we question the utility of his device. Mr. Lawson is, however, entitled to
great credit for the intelligent pains-taking, and persevering manner in which he has car-
ried on these experiments.

Notice.

In view of the fact that we are constantly recei^ang inquiries on different matters
relating to the construction and management of boilers, engines, and all matters relating
to the use of steam, and believing that many of the questions are of general interest and
importance, we have decided to open a department of answers to correspondents, in
which we shall endeavor to discuss such points as may be raised, to the best of our ability.
Engineers and firemen are especially invited to ask questions on any points which may
arise in their daily experience. Address all communications to Editor of the Locomotvce,
Hartford^ Conn.

The Superheated Water Theory of Steam Boiler Explosions.

The correspondent of the iWawj^/ac^jircr's Gazette take?, exception to the sport made
of his theory of steam boiler explosions in the Locomotive for February last, and recurs
to the subject, and cites authorities and experiments to support his views. It was not
our intention, originally, to seriously comment upon the subject, as we think any one who
intelligently examines the matter will be convinced of the absurdity of his views; but as
he cites eminent scientific men as supporting his position, it may be well to give a short
resume of the facts in the case in order that people may not be misled by his speculations.

To begin with, X seems to be completely at sea in regard to the nature of super-
heated water. He seems to consider water heated above 212° Fahr., under any condi-
tion whatever, to be superheated. This is not so. Whenever water is evaporated at a
greater pressure than that due to the weight of the atmosphere, the temperature will be
greater than 212^. Thus, to produce ebullition when the pressure is 10 pounds per square
inch by the gauge, the water must be heated to 240° ; when the steam pressure is 20
pounds, the temperature of the water will be 259^, and so on; but the water under these
circumstances is no more sujjerlieated than it is when it is quietly boiling away in an open
vessel at a temperature of 212°. Superheated water is water which is heated above the
boiling point due to the pressure on the water at the time, without giving off vapor.
Thus water heated above 212° at atmospheric pressure, or above 240° when the pressure
is 10 pounds per square inch, or above 259° when the pressure is 20 pounds would be
superheated ; and if such a state were possible in a steam boiler, it would be a source of

58 THE LOCOMOTIVE. [April,

great danger, and no one's life would be safe for an instant. We think, however, that we
can jirove by the authorities whom he quotes, that such a state of aflfairs in a steam boiler
at work is simply impossible.

The present state of our knowledge of the subject of superheating water may be
stated in the following words which are extracted from "Watts' Dictionary of Chemistry^
Vol. 3, pages 87 and 88.

" Circumstances which modify the toiling point. — Although, Avhen a liquid is heated
in such a manner that vapor can escape freely from some part of its surface, the vapor so
formed has a tension equal to the pressure upon the free surface of the liquid as soon as
the temperature of the latter reaches the boiling point, this temperature may nevertheless
be attained, and even considerably exceeded, without the formation of a trace of vapor,
if no portion of the surface of the liquid is freely exposed. These conditions can be realized
by suspending the liquid to be examined in a second liquid of equal specific gravity,
but higher boiling point.

" The phenomena which take place under these circumstances have been particularly
studied by Dufour. In order to examine them in the case of water, he employed a mix-
ture, in the requisite proportions, of oil of cloves (pi-eviously heated alone to about 200° C.)
and linseed oil. The water, already heated to 80" or 90° C, was dropped gently into the
mixture of oils, so as not to disturb the film which coated the bottom of the vessel, and
the temperature of the bath was gradually raised. Uiider these circumstances the ordin-
ary boiling point of water. 100° C, was passed without the occurrence of any perceptible
change, and traces of ebullition scarcely began to show themselves below 110° or 150° C.
Even at these temperatures, ebullition scarcely began excej^t uhen theglohules of water came
in contact with the sides of the vessel or with the thermometer. A burst of vapor then occurred,
and the globule, more or less diminished in size, was driven rapidly away, like a pith
ball after touching an electrified conductor. Th«se contacts were of course more difficult
to avoid in the case of large than of small globules ; hence the latter remained liquid, as
a rule, to higher temperatures than the former.

"In these experiments it was a rare exception when ebullition occurred between 100°
and 110° C. ; very commonly globules of 10 millimetres diameter reached 120° or 130° C,
and in one experiment the last temperature was attained by a globule of 18 mm. diam.,
and therefore containing more than 3 cubic centimeters of water. Spheres of 10 or 12
mm. diameter often reached 140° C. ; those of 5 or 6 mm. reached 165°; and others from
1 to 3 mm. attained 175° or even 178° C, temperatures at which the elasticity of the vapor
which forms at the freely exposed surface is between 8 and 9 atmosjjheres.

" At these high temperatures, the contact of a solid body very generally occasioned the sud-
den, partial, or complete vaporization of the globules, accompanied by a hissing sound like
that produced on immersing red-hot iron in water. This invariably occurred when th.e
globules were touched with pieces of wood or cJmlk, shreds of cotton, paper, etc., but not
always on contact with a glass rod or metallic wire, the difference appearing to depend
on the porous structure of the former substances. A platinum wire appeared to lose, to
some extent, by frequent usage, the power of causing sudden vaporization,

" Sudden ebullition, amounting even to an explosion, if the temperature was above 120°
C., invariably occurred on passing the discharge of a Leyden jar or induction coil through
a globule. A similar, but less violent, effect was produced by the passage of a weak gal-
vanic current. Tliese results are attributed by Dufour less to the contact of the globules
with the conducting wires, than to the disengagement of gas at the extremities of the
latter.

"Saturated aqueous solutions of various salts — for example, chloride of sodium, sul-
phate of copper, nitrate of potassium, etc., — also remained liquid at temperatures much
above their boiling points, when immersed in melted stearic acid resting on a layer of

1882] THE LOCOMOTIVE. 59

melted sulphur. * * * Jn all these cases, the same causes that operated in the
case of water, sufficed to occasion the sudden, complete, or partial conversion of the over-
heated globules into vapor.

'' These results throw important light upon the nature of ebullition, and seem to indi-
cate that it is to some extent an accidental phenomenon. In order to understand them, we
must remember that the globules being surrounded on all sides hy liquid, evaporation can-
not go on at their surface in the ordinary icay. They are, however, in a state of tension, or
unstable equilibrium, such that a very slight cause may occasion the sudden formation of
vapor of more than the atmospheric tension. The most effectual of such causes would obvi-
ously he the contact of a minute globule of air or other gas : this globule, however small,
would be a space into which vapor could be given off, and this vapor, having an elastic
force greater than the pressure (that of the atmosphere and the upper layers of the liquid)
whereby the globule was prevented from expanding, would force back the liquid walls
of the bubble of gas, suddenly converting it into a large bubble of steam. Hence, the
unfailing efficacy, in causing the ebullition of the overheated globules of liquid, of the passage
of an electric current or the contact of porous substances such as chalk, wood, paper, etc.,
which either allow air to escape from their pores when immersed in the heated liquid, or
carry down into it small globules of air adhering to them. These globules afford space
for the commencement of the formation of vapor, and this 2ii'ocess once begun, the space is
increased by the force of the vapor already foi'med within it. In the absence of any such
space, the liquid globule is in a condition somewhat analogous to that of a drop of melted
glass which has been suddenly cooled in water (Rupert's drops) and which falls to pow-
der on receiving the slightest scratch. There is no reason why the formation of vapor
should begin at one point of the mass rather than another, and thus the whole remains in
a state of molecular tension until something occurs at some particular point to weaken
the effect of the forces which oppose the formation of vapor, or until the tension increases,
(in consequence of rise of temperature) to such a degree these forces are overcome simul-
taneously throughout the whole mass." * * * *

"Another illustration of the necessity of some other cause than mere temperature in
order to bring about the ebullition of liquids, is afforded by the remarkable observation
of Professor Donny, of Ghent, that water, thoroughly deprived of air and sealed up in a
rather long glass tube quite free from air, maybe heated to 138° C, at one end of the
tube without boiling, and is then suddenly and violently thrown to the other end by a
burst of vapor."

Observe now, the conditions which are absolutely necessary for the jiroduction of
superheated water.

First : — No portion of the surface of the water can be exposed to the atmosphere or
any other vapor or gas.

A very little reflection will suffice to convince any one of ordinary intelligence that
this state of things is quite impossible of attainment in a steam boiler. For, when the
boiler is first filled with water and the fire is started, the surface of the water in the boiler
is freely exposed to the air in the steam-space, and after steam has once begun to form,
not only the surface of the water but the greater portion of the interior of the water is in
intimate contact with steam which has formed, and which, once begun, must continue to
form as long as heat is applied.

Second : — The water, already heated to 80° or 90° C, must be gently dropped into the
mixture of oils, which must previously be heated alone to about 200° C.

This requires very little comment. Boilers (in this part of the country at least) are
not generally filled with a mixture of oil of cloves and linseed oil mixed in such proi)or-
tions that its specific gravity is just equal to that of the feed- water at varying tempera-
tures, and then raised to a temperature of 200° C, and the feed-water "carefully drojiped

60 THE LOCOMOTIVE. [April,

in." If there are any boilers running in this vicinity, which are operated as above, we
would like to know it, so that we could observe their action and study their economy.

Third : — The contact of a solid body, or the smallest particle of air or gas of any kind
is fatal to the success of the experiment.

The contact of the solid body is always obtained from the shell of the boiler, the
tubes, braces, etc., and that of a gaseous body is always obtained from the atmosphere,
and steam, as we have seen above.

Fourth : — If the steam has once commenced to form, it goes on and cannot be stopped,
even under the conditions above enumerated until the water is all evaporated.

This last point seems to be the one on which all the superheated-water-explosion
theorists run aground. All the precautions which must be taken to prevent ebullition at
high temperatures are poioerless to stop it when it has once legun. X says : " I contend that
it is possible to have the water in just the quiescent condition described," (that is, so
quiet that it may be superheated). "Practical experience indicates this. I am running
an engine, taking its usual amount of steam. I try the upper guage and find water, or
steam and water. I shut off the steam and again try the guage, when no water comes —
nothing but steam. A moment later I turn the next cock and no water flows. The
boiler fire is equal to the maintenance of the same steam pressure that it was when the
engine was running, still ebullition is ceasing. Does not this indicate that steam is not
forming — that the water is becoming quiescent ? The heat, however, is entering the
water; what is its efiectifit does not produce ebullition? As Prof. Cotterill says, it
superheats the water, and what is more probable than that, it is this superheated water
which is the cause of so many boiler explosions ? "

No, Mr. X., ebullition is not ceasing; it does not indicate that steam is not forming;
and Prof Cotterill does not say " it superheats the water, and what is more probable than
that it is this superheated water which is the cause of so many boiler explosions ? "

The absence of water when you open your gauge after shutting off steam merely indi-
cates that your boiler foams to a greater or less extent : That steam is forming, and will in-
variably continue to form unless you take measures to check your fire, you will readily per-
ceive by watching your steam-gauge. And this is what Prof. Cotterill says : " If perfectly
quiescent water, perfectly free from air or other foreign substance, be heated in a clean glass
vessel the temperature may be raised far above 212° Fahr. without occasioning ebullition.
* * * * jf smjii an effect could be produced in the circumstances of an ordinary
steam boiler it would be a source of great danger, * * * * although it is certainly
possible that some of the numerous cases of explosions which have occurred immediately
after starting an engine may be accounted for in this way, yet the circumstances under
which the effect is produced are rather those which occur in a laboratory, than in actual
practice. * * Subject to these observations, the elastic force of steam is always con-
nected with its temperature, so long as it remains in contact with water, no matter how
the steam has been produced ; thus if instead of supposing the water confined in a cylinder
provided with a piston which rises as the steam is formed, we suppose the steam to be pro-
duced in a closed steam boiler, then the temperature and pressure will keep rising as more
and more heat is added, instead of remaining stationary ; but the relation between pressure
and temperature remains precisely the same so long as any water is left.''''

This certainly does not sound much like saying that the water in the boiler becomes
superheated when the steam is shut off.

This article, however, is already long enough ; if necessary we will recur to the mat-
ter again next month, when we shall refer more particularly to Prof. Donny's and Mr,
Lawson's experiments; which last, by the way, X. refers to in support of his views,
although we have yet to learn that Mr. Lawson sees any connection between his experi-
ments on the concussion of water, and superheated water. H. F. S.

1882.] THE LOCOMOTIVE. 61

Safe working pressure for Steam Boilers.

There has been so much said and written about the proper factor of safety for steam
boilers, and the working pressure which should be allowed, that anything more on the
subject might seem superfluous; but as there seems to be a deep and wide-spread ignor-
ance, even among the best-educated engineers, as to the ultimate strength of iron under
the conditions which obtain in practice, perhaps a few words may not be out of place here.

The working pressure of boilers is generally fixed directly from the ultimate tensile
strength, so called, and is fixed by different authorities from ^^ to |^ of the bursting pres-
sure, or what is the same thing, so that the strain on the plates is from ^ to ^ of the ten-
sile strength of the iron of which they are composed. This tensile strength is obtained
by subjecting small pieces of the material to tensile stress in a testing machine, and ob-
serving the force required to pull it asunder. Now the results obtained by tests con-
ducted in such a manner are undoubtedly very useful in some cases ; but for practical
use they are decidedly misleading, for the circumstances and conditions of the test are
totally different from those which surround the material in practical use, in such struc-
tures as steam boilers, or bridges, for example. In the case of the test we have a gradually
increasing stress applied until fracture takes place. In practice we have a somewhat
lighter load many times repeated, the number of repetitions depending mainly upon the
nature of the structure, while other forces are sometimes called into action, the extent of
which are in many cases quite indeterminate.

Now it is well known that a stress much less than that required to produce failure by
a single application, if often removed and repeated, will cause the rupture of any given
piece of material. It is also well known that the magnitude of this stress is even less
than the " elastic limit" in the case of iron, and bears no very definite ratio to either the
elastic limit or the ultimate strength. It is also well known that, if this stress is applied
in opposite directions alternately, we can break any given piece of material with much
less force than we can by applying it in one direction only.

A very simple experiment will suffice to demonstrate this conclusively. Suppose
we have a bar of iron which we wish to break. We secure one end in a vice, and, grasp-
ing the projecting part with our hands, we exert all our strength. The bar remains
intact, and if we release it, it springs back to its original position. We try agttin, and
again, and after awhile the bar shows signs of weakening, and if we continue our exer-
tions we finally break it, without, at any time, applying more force than we did at first.

Again, if instead of exeiling our strength in bending the bar in the same direction
each time we pull in opposite directions alternately, we shall find that we can eventually
fracture the bar with the exercise of only one-half the force which we exerted when we
bent it in the same direction each time. This shows that the force required to fracture
the bar does not depend exclusively on the maximum force applied^ but that two very
important factors, to be taken into account in estimating the ultimate resistance of the
material, are the number of repetitions of the stress, and the range of variation of the
stress.

These principles seem to be very well known to every one, and we apply them al-
most instinctively every day of our lives, yet, strange to say, they have received scarcely
any attentioh, scientifically, at the hands of engineers, and they have gone on, always
testing materials in the same way for elastic and ultimate strength, and then trusting
blindly to a large " factor of safety " (where experience has shown them that it was abso-
lutely necessary) instead of investigating the specific action of live loads under circum-
stances similar to those in practice. The factor of safety as generally applied might,
with much more propriety, be called a factor of ignorance.

The only definite experiments bearing on this subject that the writer is aware of are
those begun by Wohler, in Germany, and continued by Spangenburg. It appears to

62 THE LOCOMOTIVE. [April,

him that the above-mentioned experiments have not received the attention from engi-
neers that the very great importance of the subject would seem to warrant. These ex-
periments, although quite extensive, have not been carried out far enough to enable us
to deduce decisive rules for practice, in every case ; still they are sufficiently extensive to
enable us to arrive at a tolerably correct estimate of the proper load for iron, under some
of the more simple conditions of practice. They show conclusively that the ultimate
tensile strength of ordinary wrought iron subjected to an indefinite number of repetitions
of tensile stress, is not over 30,000 pounds per square inch on an average.

This tten should be taken as the ultimate strength for such structures as steanfi
boilers, where the stress is always in one direction. The variation of stress in this case
is from zero to the maximum working pressure. If the stress due to the steam pressure
was the only force the boiler had to resist, we might safely load the iron nearly up to the
limit of 30,000 pounds per square inch, but such is not the case. Due allowance must be
made for the deteriorating influences of the intense lieat to which the plates are sub-
jected, as well as corrosion and other causes which tend to destroy the original strength
and elasticity of the iron. The amount of the straining actions due to the influence of
heat is quite indeterminate, and varies largely with the design and construction of dif-
ferent boilers, as well as with the care and management which they receive. An exami-
nation of the records of the behavior of some thousands of boilers, mainly of the return
tubular and drop-flue types, shows that under ordinary circumstances a factor of safety
of from two and one-half to three, calculated on the alove basiSy is amply sufficient.
Boilers run with the above factor may safely be depended on for a period of upwards
of fifteen or sixteen years. Beyond that time, unless the conditions under which they
have been used are more than usually favorable, it will be found prudent to run them
at a somewhat reduced pressure.

Of course the 30,000 referred to above, as the ultimate tensile strength under re-
peated stress, cannot be taken as absolutely correct for all kinds of iron. It is merely the
average value obtained by Wohler from the iron he experimented upon. There is very
great need of complete and trustworthy experiments on the subject in this country, and
it is to be hoped that they may be made before long. When we know accurately the
limits to which the materials used in engineering works may be safely loaded, and re-
tain their strengtli for an unlimited time, then, and then' only, can we fix reasonable
factors of safety. H. F. S.

Smallest Locomotive in the World.

Henry Case, of Jamestown, has constructed a perfect locomotive that is the smallest
of any in the world. He spent the best part of eight years in its construction. Follow-
ing is a description of the miniature engine : The engine measures in length, 8^ in., with
tender, 12 in.; its height, 3^ in.; gauge, If in.; length of boiler, 4| in.; diameter of boiler,
1| in.; fire-box, | in. square and 1 in. deep; diameter of drivers. If in.; diameter of truck
wheels, ^ in.; stroke of piston, ^ in.; diameter of cylinder, -^^ in.; stroke of valve, ^^^ in.;
eccentrics, ^" diameter; length of links, ^ in.; width of links, ^ in.; link-blocks, -^.j in.
square; length of main and parallel rods, 1 fin.; put together with straps, gibs, keys,
set-screws, bolts and half-boxes, with oil-cups. Whistle, /^ in. in diameter; steam-gauge,
^ in. in diameter; diameter of gong, ^ in.; glass water-gauge in cab ; lamp in cab bums
one hour; heater pipes and blower-pipes, -^^ in. in diameter ; headlight -^^ in. square, and
burns 20 minutes; pop safety-valve in dome. The pumps throw one drop of water per
stroke. This engine has 585 screws to hold its parts together. It weighs 1^ pounds,
with tender, 2 pounds 2^ ounces. — Rochester Democrat.

1882.] THE LOCOMOTIVE. 63

ExpLOSioxs IN Flour Mills. — A Parliamentary paper just issued contains a report
by Mr. Thomas J. Richards, of the Consultative Branch, Board of Trade, to the Home
Secretary, respecting an explosion which took place on September 14th at the corn-mill
of Messrs. Fitton & Son, at Macclesfield. The eflfects were of a very disastrous character,
a large part of the mill at the north end being levelled with the ground, and the roof
over a much larger area destroyed, and the engine man being killed by the fall of part
of the building. The damage to the mill was estimated at between £5,000 and £6,000.
It appears that some millstones had been running empty at the time of the explosion,
that a flame was produced between the millstones, which was sufficient to ignite the
flour-dust diflfused in the millstone cases, and which being transmitted along the passage
to the stive-room by the continued ignition of dust, would cause an explosion of the
flour-dust in the stive-room. Mr. Richards has been making general inquiries into the
question of fires and explosions in corn-mills. He says that the elements of danger exist
in all corn-mills more or less, and notwithstanding the comparative rareness with which
disasters of magnitude occur, they are ever liable to take place. Ignitions of flour-dust
are apt to cause slight explosions, which, jarring greater bodies of dust into a cloud, are
liable to ignite and cause a serious explosion or a general firing of the mill. Whether
the eflfects of the ignition of dust are serious or slight, depends upon the conditions
existing at the time. "A large number of fires occur in corn-mills the origin of which is
unknown. Mr. Chatterton, the Secretary of the Millers' Mutual Fire Insurance Company,
informs me that he has records of 84 serious fires which have occurred in corn-mills since
1876, the origin of 56 being unknown. A majority of those unconnected with the milling
business are probably entirely unaware of the danger which may exist in consequence of the
presence of a building devoted to the useful, and, to all appearance, harmless occupation
of the cleansing and grinding of corn, and the dressing of flour. That insurance com-
panies are alive to the extra risks incurred in corn-mills is shown by the high rate of
insurance charged for corn-mills, which I am informed is about 18«. to 208. per cent."
Mr. Richards adds: "A subject of interest allied to that which has been considered is
that of the risks involved in the cleaning and grinding of rice. The experiments I have
made on rice stive-dust and ground rice convince me of the facility with which they, and
particularly the former, will explode when difi"used in air. That the risks involved in
rice cleaning and milling are greater even than in com milling is evidently indicated by
the high rates of premiums charged by insurance companies, and that some companies
will not accept them at any rate. I am informed that the rate of insurance for rice-mills
in London is £6 6«. per cent. It is, however, stated to be much less in the country." —
London Times, February 27th.

To prevent the formation of rust on cast-iron, Mr. J. J. Shedlock, of Uxbridge, has
patented in Germany the following process : The objects are exposed to the action of
dilute hydrochloric acid. The acid dissolves the iron on the surface, and leaves a layer
of carbon, or graphite. This layer cannot be destroyed by caustic agents. The pieces
are then washed in a cistern with water or steam, in order to take away the iron salts
which have formed. The liquid is removed from the cistern, in which the air is rarefied,
in order to remove all the water from the articles. A volatile solution of caoutchouc is then
brought into the apparatus, by means of which all the pores of the crust formed on the
iron are filled. The volatile solvent is then removed by heating. — Mechanical World.

If down his throat a man ghould chooee.

In fun to jump or slide,
He'd ecrope his phoes ngainnt his teeth

Before he went inside.
Or if hi« teeth were lost or gone.

And not a stump to scrape upon,
He'd see at once now very pat,

His tongue lay there, by way of mat,
And he would wipe his feet on that.

THE LOCOMOTIVE.

[April.

Incorporated
1866.

Charter Per-
petual.

Issues Policies of Insnrance after a Careful Inspection of tlie Boilers,

COVERING ALL L088 OR DAHAOB TO

BOILERS, BUILDINGS, AND MACHINERY,

AEISiyO FROU

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full information concerning the plan of the Company's operations can be obtained at the

Or at any Agency.

J M. ALLEN. Prest. W. B. FRANKLIN, Vice-Prest. J. B. PIERCE, Ssc'y.

Soard. of Directors t

J. M. ALLEN, President.

LUCIUS J. HENDEE, Preet. ^tna Fire Ins. Co.

FRANK W. CHENEY, Treas. Cheney Brothers Silk

Manufacturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Amer. Nat. Bank.
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Manufacturing Co.
THOMAS O. ENDERS, of ..Etna Life Ins. Co.
LEVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Hon. HENRY C. ROBINSON, Attorney at Law

Gen. WM. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire

Arms Mfg. Co.
GEO. CROMPTON, Crompton Loom Works, Wor-

Hon. THOS. TALBOT. Kx-Govemor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manuflicturer, Provi-
dence, R. I.

NELSON HOLLISTBR, of State Bank, Hartford.

CHA8. T. PARRY, of Baldwin Locomotive Works,
Philadelphia.

GENERAL AGENTS.

THEO. H. BABCOCK,
CORBIN & GOODRICH
LAWFORD & McKIM,
W. S. CHAMBERLIN,
J. L. SMITH,
H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

CHIEF INSPECTORS.

R. K. McMURRAY,
, WM. G. PIKE,
JOSEPH CRAGG,
WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN,
J. H. RANDALL,
A. C. GETCHELL,
J. S. WILSON,

OFFICES.

New York City. Office,

Philadelphia.

Baltimore.

Boston, Mass.

Providence, R. I.

Chicaoo, III.

St. Louis, Mo.

Hartford.

Bridgeport.

Cleveland.

CiNOIICNATI.

285 Broadway.
430 Walnut St.

10 So. Holliday St.

10 Pemberton Sq're.

15 Weybosset St.
1S2 La Salle St.
404 Market St
218 Main St.
328 Main St.
846 Superior St.

53 West Third St

Sfo

0C0ttt0titI^.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series — Vol. III.

HARTFORD, CONN., MAY, 1882.

No. 5.

Proportions of Riveted Joints.

No one can deny the fact that the safety and durability of a steam boiler depends
as much on the proper riveting of its joints as it does on any other element of its
construction. This being the case, let us briefly examine the matter of proportioning
joints for difl"erent thicknesses of plates as it is now practiced by difierent boiler-makers,
and see what we can learn.

We have long lield the opinion that there is too much guess work, and too little cal-
culation free from prejudice or preconceived opinions, used in the determinati(m of the
proportions for joints in the different thicknesses of boilerplate. No two men use the
same proportions, and each and every one is confident that he is just right, for he has
learned by experience that no other proportions than tliose he uses are admissible.
While we do not wish to be captious, or to deprecate the practical knowledge gained by

Fig. 1.

boiler-makers through the medium of their every-day work, we cannot help saying that
in our opinion, based on very wide observation, very few boiler-makers use their mate-
rials to the best advantage.

A very little reflection will make it clear to the mind of any intelligent mechanic,
that in order to obtain the greatest strength of a riveted joint with the least amount of
material and labor, the diameter and pitch of rivets should be so proportioned that the
shearing strength of the rivets will be equal to the tensile strength of the section of plate
left between rivet holes. As the tensile strength of ordinary boiler plate is practically
equal to the shearing strength of rivet iron, the only condition to fulfill is to make the
area of the rivet holes equal to the net section of plate after punching. This condition
is rarely fulfilled in practice. No effort seems to be made to even approximate to it. For
instance, when one man uses these proportions: Plate -^\" thick, rivet |"diam., pitch 2^",
and plate ^" thick, rivet f" diam., pitch 2 ; and another man these: Plate ^^g" thick,
rivet I" diam., pitch 1§" ; and plate ^" thick, rivet |" diam., pitch 2^"; we cannot help
thinking that very little judgment has been used in one case or the other. These are not
imaginary proportions but were given us by the boiler-makers who practice them daily,

THE LOCOMOTIVE.

[Mat,

and they are ready to maintain that no other proportions can be used successfully for th-

above thickness of plate.

To determine the relative strength of the plate and rivet at the joint, we have only

to apply the following simple rule, when the plate and rivet are both iron,

Pitfh — diameter of rivet holes ,., ^ „, .. riix-'x

equals the percentage of strength of plate at joint as

Pitch
compared with solid plate.

Area of rivets x No. of rows of rivets

equals the percentage of strength of rivets at

Pitch X tliickness of plates
joint as compared with solid plate.

For the sake of illustrating the great diversity of practice among different boiler-
makers, we have obtained the proportions of joints used by some of the more prominent
boiler-makers throughout the country, and s.ubmitted them to analysis by tlie above rules.
The results are given in the following pages. It will be seen that some of them are very
well proportioned, indeed, while others are very badly proportioned. The iigures given
speak for themselves. Referring to Fig. 1 we have,

Plate i" thick. Rivet holes ]V' diam. Pitch of rivets, If.

1 QO'R 6875

Strength of plate at joint = — — j c^f^ = 63 per cent, of solid plate.

371'^2
Strength of rivets at joint = ^^.- ^^^~ = 79 per rent, of solid plate.

The rivet strength is greatly in excess of that of the plate; hence the pitch slioukl
be increased. This would 'give a stnmger joint with less work and material.

Fig. •>.

Fig. 2. Plate f thick. Rivet holes |i" diam. Pitch of rivets, 2".

Strength of plate at joint = ^ — — = GG per cent, of solid plate.

371 22
Strength of rivet at joint = ^ — ^ =74 per cent, of solid plate.

A stronger joint than Fig. 1, although there is still an excess of strength in rivets.

Fig. 3.

1882.]

THE LOCOMOTIVE.

Fig. 3. Plates t;V' and f" thick. Rivet holes, f" cliara. Pitch of rivets, 1|".
Strength of plates at joint - — j^^^ = 60 per cent, of solid plate.

Strength of rivets in ^V' P^ate = i.s75x^.3125 = '^^ P"^"" *^^°*- ""^ ^""^'"^ P^""*^'
Strength of rivets in |" plate = ^ g/g^ ^ ^375 = ^^ Pe^ cent, of solid plate.
Too many rivets, pitch should be increased. Impossible to proportion joints cor-
rectly with different thicknesses of plates, and same sized rivets and equal pitches.

Fig. 4.

Fig. 4. Plate A" tbick. Rivet holes |" diam. Pitch ot rivets, 2"

= 62^ per cent, of solid plate.

Strength of plate at joint =

2 —

.44179

Strcn ,th of rivets at joint = 'TT .i.,- = 71 per cent, of solid plate.

* X .Ol'iO

Plate cut away too much, rivets should be spiced farther apnrt.

rFiG. 5.

Fig. 5. Plate /g" thick. Rivet holes 4|" diam. Pitch of rivets 2^".
Strength of plate at joint = ^'^^l',^^^^^ = 62 per cent, of solid plate.

2.125
.51849

Strength of rivets at joint = 2 125 x .3125

Pitch about right. Rivets larger than is necessary

- — z = 18 per cent, of solid pia^e.

THE LOCOMOTIVE.

[May.

Fig. C.

Fig. 6. Plate Nos. 3, 2, and 1. Rivet holes \l" diam. Pitch ot rivets 1|".
Strength of plates at joint = "^ ^.. — — = 63 per cent, of solid plate.

l.nio

.37122

Strength of rivets at joint No. 3 plate = 1, — ''"^.^. = 76 per cent, of solid plate

.37122

Strength of rivets at joint No. 2 plate = .. '' J'^^osj. ~ ^^ P®'^ ^^'^*'* °^ solid plate.

.37122

Strength of rivets at joint No. 1 plate = ^,. ., = 66 per cent, of solid plate.
Pitch too small, especially for Nos. 2 and 3. Same remarks apply as in the cas3 of

Fig. 3.

Fig. 7.

Fig. 7. Plates Nos. 0, 00, and f". Rivet holes |" diam. Pitch of rivets 1|".

Strength of plates at joint = ''~''' = 60 per cent, of solid plate.

44179
Strength of rivets at joint in No. 0 plate = ' , ^ = 69 per cent, of solid plate.

44179

Strength of rivets at joint in No. 00 plate = ^'^ ^^5 = 66 per cent, of solid platu

l.o<5 X .o5o

Strength of rivets at joint in |" plate =

.44179

1875 X .375

63 per cent, of solid plate.

Fig. 8. Plate f" thick. Rivet holes 4|" diam. Pitch of rivets, 2f' .

2 2,5 81*'o

Strength of plate at joint = -^^^^^-K-^i — ^ = 64 per cent, of solid plate.

Strength of rivets at joint = -r-^ ^^ = 62 per cent, of solid plate.

A first-rate proportion for |" plate.

1882.]

THE LOCOMOTIVE.

Fig. 8.

Fig. 9.

Fig. 9. VX&te -^^" ih\ck. Rivet holes |" diam. Pitcli of rivets, 2|^".

2.35 — .875

Strength of plate at joint =

a. 25
.60132

= 61 per cent, of solid plate.

Strength of rivets at joint = » »- ^ ' ^f- ~ ^1 per cent, of solid plate.
A well proportioned joint.

Fig. 10.

THE LOCOMOTIVE.

[May,

Fig. 10. Plates fj" and ^" thick. Rivet holes, ||" diam. Pitch of rivets 2".

Strength of plate at joint —

.8125

= 59 per cent, of solid plate.

Strength of rivets at joiiit in -^-^' plate = o v 4'^'"' ~ ^^ ^^^ cent, of solid plate.

51849
Strength of rivets at joint in ^" plate = ' -x = 53 per cent, of solid plate.

Rivet too weak for ^" plate. It would be better to use larger rivets and greater
pitches in both cases. See Fig. 3.

Fig. 11.

Fig. 11. Plate i" thick. Rivet holes ff" diam. Pitch of rivets 2f' .

2 5 9375

Strength of plate at joint = — — ^^ = 62^ per cent, of solid plate.

Strength of rivets at joint

Rivet about right, but pitch should be slightly lessened.

2.5

690'^9
-^x — "^^—z = 55 per cent, of solid plate.
2..D X .0 ^ ^

Fig. 12.

1S82.J THE LOCOMOTIVE. 7t

Strength of plates at joint = — — ;y^ = 58 per cent, of solid plate.

Fig. 12. Plates -^" and |" thick. Rivet holes \^" diaui. Pitch of rivets, 2^".

} .20 — .9375

2.25

fifl0*'9
Strength of rivets at joint in ^^" plate = .^ .^1 ' ~-p.^- = 54^ per cent, of solid plate.

Strength of rivets at joint in |" plate --= k-^- — ^^tt^ = 49 per cent, of solid plate.

Rivets and pitch both too small, especially for tiie |" plate. See remarks under
Fig. 3.

The foregoing figures show most of the proportions used for single riveted lap joints.
Our next number will be devoted to douhle riveted joints, and we shall endeavor to call
attention to some important points wliich are generally overlooked by boiler- makers.

Inspectors' Reports.

Marcit, 1882,

The one hundred and eighty-sixth monthly report of the Inspection Corp^ shows
the very gratifying fact, that the number of boilers inspected during the month of Manli
last, was over 22 per cent, greater than for the corresponding month last year. Tiie
number of visits of inspection made was 2,070; the total number of boilers examined
was 4,642; while the number of complete internal inspections foots up 1,*)08. The
hydrostatic test was applied in 326 cases.

The number of boilers condemned was 50. Below is given the usual analysis of the
defects found.

Nature of defects. Whole number. Dangerous.

Cases of deposit of sediment, . . . -

Cases of incrustation and scale, . . . -

Cases of internal grooving, - . - - -

Cases of internal corrosion, - - - - -

Cases of external corrosion, - - - - -

Broken and loose braces and stays, - - - -

Settings defective, ..-.--
Furnaces out of shape, - - - - -

Fractured plates, ...---
Burned plates, ...--.

Blistered plates, ..--.-

Defective riveting, -..-.-
Defective heads, .-.---

Leakage around tubes, .....

Leakage at seams, ......

"Water-gauges defective, . . . - .

Blow-out defective, ......

Cases of deficiency of water, . . . .

Safety-valves overloaded, - . - . .

Safety-valves defective in construction, . - -

Pressure gauges defective, .....

Boilers without pressure gauges, ... -

Total, 2,382 526

231

362

101

116

3:i

108

164

100

245

224

, -

227

105

- . 4

132

72 THE LOCOMOTIVE. [Mat,

There seems to be a desire on the part of certain people to promulgate the belief
that the Hartford Steam Boiler Inspection and Insurance Company is always ready to
insure " anything in the shape of a boiler," for money. In accordance with this scheme,
every accident to any boiler under our care is eagerly pounced upon, spread throughout
the country with a great flourish, and the opportunity improved to throw all possible
odium upon -the company and its operations generally. This, we wish to be distinctly
understood, is a very great mistake. This company always refuses to insure anything
that, in the judgment of its trained inspectors, is not perfectly safe, if properly managed;
and we will remark here, that no boiler whatever is safe for one minute, unless it is
properly managed. If we chose to publish the fact every time we declined to insure a
boiler, and give the locality of the boiler, and our reasons for declining to accept a risk
on it, we think we could keep the public in a chronic state of alarm throughout most of
the territory in which the company operates.

"We have lately received from the agent of the company in a certain district where
an explosion has lately occurred, a canceled policy, with a memorandum accompanying
it from the chief inspector, which so peculiarly illustrates the matter in question, that
we give it verbatim for the benefit of the public. Similar cases are constantly occurring,
as we can prove to any one who is sufficiently interested in the matter to investigate it.

The following is the memorandum which accompanies the canceled policy in
question : —

This party, after insuring with us, found his boiler leaking one day, and by a second-
hand dealer was induced to change it for another; which other, we reported to him, was
not a good one. Nevertheless, he put it in without informing us, and we insist on can-
celing from date of change, Feb. 16th, 1882. , General Agent.

The following is the report of the inspector upon the boiler in question, which is
now running in a busy street in a populous city :

To J M~^-.

Report of an Internal and External Examination of your Steam Boiler made by us,
Feb. 16th. 1882.

Locomotive boiler wMth engine bolted fast on top. Furnace very badly pitted and
corroilcd away. Blistered on back leg externally. A spot where blistered, was covered
up and filled flush with putty to hide defect. Dangerously eaten away around hand-
hole on back hg. Furnace sheets bulged in several places, also on front head around
hand hole. Sh<'ll near back end cracked. Owing to poor condition, and considering it
unsafe, we respectfully decline to continue our insurance on this boiler.

Very Resp'y, , Chief Inspector.

The above is a fair sample of many cases that have occurred in our experience. If
the boiler in question gives out and any one is killed, we shall anxiously await the coro-
ner's verdict, and the official inspector's explanation of the disaster.

Notice.

Wanted: — At this office, copies of The Locomotive, No. 10, Volume IV, August,
1871, for which 50 cents per copy will be paid. Must be in good condition for binding.

Partii'S having the above copies to spare wuU confer a favor by communicating with
this office.

1882.] THE LOCOMOTIVE. 73

Getting up Steam.

The following communication lately received from a well-known dealer in machin-
ery, is a very good illustration of one way to get up steam — and keep it after you have
got it.
Editor Locomotive :

W-e have a story too good to keep. A gentleman applied to us for a "cheap
boiler," one that •' would be good for two pounds or so." The only one we had had just
been tested at 150 lbs. to the square inch, but that was "too good." He said he once
bought one for $30.00, and ordered a young man in his employ to get up steam in it.
He went away and was gone longer than he expected, and on his return he found a rag-
ing fire in the furnace, a pot filled with bricks on the safety valve lever, and a very much
frightened young man hanging on to the same lever with all his weight, and both hands.
The boy said in explanation, that he didn't know anything about a boiler, but he sup-
posed that if he " let any steam get out of that thing on top, it would blow him and the
shop to smithereens." "Ah!" said he, "I'm glad ye came, for I couldn't howld it
much longer." It evidently came very near being another mysterious (?) explosion.

Yours, &c., J. S. M.

Krupp's Muzzle Pivot Gun.

The Germans seem determined to be ahead of this or any other country, in their
practical efibrts towards the adoption of every new idea in scientific warfare that will
give them power in Europe. Once more Herr Krupp has come to the front. This enter-
prising maker of warlike material, has recently conducted a series of experiments with a
new kind of gun and shell. The gun is on the muzzle pivoting system, and the shell has
been specially designed for torpedo effect, that is, to burst on penetration of armored
ships with a result similar to the explosion of a torpedo. The idea of the muzzle pivot
gun is not novel. It has been known to our War OflSce authorities for some years ; but
they have not thought proper to thoroughly or practically test its utility. They have
during late years been either allowing what little inventive faculty they possess to lie
dormant, or have been content with watching the operations of other powers in the
direction of improvements in ordnance and other warlike material, and then copying
their results. Unfortunately, the latter has only become too patent, and the position
which Great Britain has consequently slipped back to, is now admitted by every practi-
cal or scientific person. Herr Krupp's recent experiments at Meppen were considered to
be highly satisfactory, and quite suflRcient to justify the great German manufacturer of
weapons, in taking immediate measures for the production of larger guns and shells than
those tried. The gun experimented with was of 21 centimetre calibre, with a long
shell having a tremendous bursting charge, so arranged that the shell should explode
only after penetrating some distance into the armor plating. The gun's muzzle pivot is
carried down into a socket fixed in the hold of a vessel, in such a way as to prevent the
slightest recoil even with the heaviest charge. Herr Krupp's gun was worked during
the trials with great ease and certainty of aim, and obtained for the shell a very high
velocity. This description of weapon has been designed for gunboats built to carry guns
up to 40 centimetres. These gunboats are to be of light draught, high rate of speed,
and exceedingly handy. In fact, two or even three of such armed boats would be very
ugly customers for a first-class armored ship to cope with, owing to, their rapid power
of manoeuvring, and their small size rendering them difficult to hit. Their cost would
be but an eighth or a tenth of a first-class ironclad. The Germans are certainly a very
practical race. A good idea once conceived and well considered in all its bearings, they
then do not take very long to work it out. We shall hear more ere long of Herr
Krupp's muzzle pivoting guns and torpedo shells. — Engineering,

74 THE LOCOMOTIVE. [Mat,

^t^

HARTFORD, MAY, 1882.

On another page will be found a paper on " Running Iron Worls on the Sabbath,''^
read before the meeting of the Sabbath Observance Convention, recently held at Pitts-
burgh, by Mr. John Fulton of Johnstown, Pa., which is so thoroughly in accord with
the sentiments of all good people who are anxious that the present and rising genera-
tions shall not drift away from the customs of our fathers into indifference and skepti-
cism, that we ask for it a careful reading.

In times of great business prosperity, when every manufacturing establishment is
driven to its fullest capacity, it is easy for the manufacturer to persuade himself that he
can better make repairs on Sunday than to stop his works on week days. The cu;stom is
quite common in manufacturing communities, and even among some good men it is
regarded as necessary work.

Our attention is especially called to this subject by this frequent demands for inspec-
tions of boilers on Sunday, and if all these demands were complied with, our inspectors
would be employed every Sunday in the year.

We believe firmly in the observance of the Sabbath — that every employee should
have that day uninterrupted to himself. No business is so important or driving that
one day in the year cannot be afforded for the examination of the boilers. We appeal,
on behalf of the Inspection Department, to all manufacturers, to elect some day other
than Sunday for the examination of their boilers. We are not superstitious, but we
believe it will be a gain to every one to so arrange their business as that the Sabbath
will not be violated, but that every person employed can feel that it is truly a day
of rest.

Akticle on Riveting in the Miller's Journal for May 17, 1832, taken verbatim from
The Locomotive for September, 1881. No credit.

Article on Boiler Tubes taken from The Locomotive of May, 1881, including ac-
count of our experiments. No credit.

The Boston Journal of Commerce now appears in quarto form, cut and pasted.
This improves its form very much, as it is vastly more convenient. The matter does not
need improving as it is always the very best. It is worthy of note in a recent number of the
American Naturalist^ in an article on cotton fiber, special attention is called to the micro-
scopic investigations of cotton fiber by the editor of the Journal of Commerce. He is
among the first to turn microscopic investigation in this direction. We are jjleased to
make this note of a progressive paper, managed by a progressive man.

The report of Mr. Henry Hiller, chief engineer of the National Boiler Insurance
Company, Limited, Manchester, England, for 1881, has just been received. It contains
much that is interesting in regard to defects in Steam Boilers, their cause and remedy.
Statistics relating to explosions in England during the past year, and fac similes of sev-
eral indicator diagrams, which illustrate in a very forcible manner the value of the indi-
cator to the steam user, who wishes to economize in the use of coal.

1883.] THE LOCOMOTIVE. 75

In the Iron Trade Report for March, 1882, issued by Rolling & Rowe, of London,

Eng., extensive manufacturers of iron and steel, we find the following startling statement :

" The total losses of ships of all nations during 1881 is estimated as follows: 425 steam

vessels; 2,750 sailing vessels; total, 3,175. Tonnage, 1,250,000, or more than the whole

tonnage launched during the years 1878, 1879, and 1880.

The series of articles on Structural Steels by Albert F. Hill, C. E., now appearing in
The Iron Age and Mechanics, are of very great interest and value to iron-workers gener-
ally, and boiler-makers especially.

Running Iron Works on the Sabbalh.

At the recent meeting of the Sabbath Observance Convention, at Pittsburg, a paper
•was presented by Mr. .John Fulton of Johnstown, on " Iron Works on the Sabbath," the
main points of which we give below. After stating the obligations and necessity of
keeping tlie Sabbath, and the results of experiments to abolish it, he continues:

There are other claims arising in the several branches of industry, which are sought
to be added to the exemptions to excuse the sin of Sabbath work. At iron works, in
blast furnaces, it is alleged that the nature of the operations of iron making requires'
continuous work, especially in the production of a uniform quality of pig iron for Besse-
mer steel. That to produce a graphitic, or gray pig iron, there must be sustained heat,
and therefore continuous blast into the furnace. It is not contended, by any person at
all familiar with blast-furnace operations, that the furnace work cannot be suspended
over the Sabbath, for the fact is well known that the operations have been suspended,
during times of repairing furnace, for twenty-four, forty-eight, and seventy-two hours.
It is difficult, if not impossible, to believe that any intelligent manager of inm works,
superintendent of furnace or furnace keeper, can seriously entertain the idea that furnace
work compels men to break the Lord's day. For this would be assuming them to oc-
cupy the fearful attitude of impeaching the Divine wisdom, in charging God with fool-
ishness in requiring men to "keep holy the Sabbath day," and yet ordaining a physical
law to abrogate or nullify His spiritual law! No. This is not their attitude. For
every intelligent furnace superintendent knows, that it is quite practicable to rest the
furnace on the Sabbath day. That in suspending the blast heat, compensation must be
made for it by increased charges of coke or other fuel, at such time, near the close of the
week, so that it may come into action during the suspension of the hot blast.

A large number of furnaces rest on the Lord's day, both in this country and Europe.
Seventeen are reported from one state to London Iron., without exhausting the record.
Baird, of Scotland, rested all his furnaces on the Sabbath day, and closed a very success-
ful life, by a final donation to the Lord's treasury of a quarter million of dollars. But
there exists a certain undefined and undefinable fear that if the Sunday work is abated,
there may be a falling ofl" in quantity of pig iron produced. That as others do it there
must be some unexplainable virtue in continuous work, and hence each works, fears to
initiate the Sabbath rest reform, lest they may sufi'er loss and be exposed to ridicule.
One famous manager testifies: "We do not claim that we can make as much iron in six
days as we could in seven, but in the long run — a year — the Sabbath -keeping furnaces
make more than those who do not rest." The fact is submitted here that obedience to
God's laws insures the best results, physically, morally, and financially. That violation
of law is destructive in every respect, body, soul, and pocket. With the accurately kept
statistics of furnaces and iron works, the economy or loss of Sabbath-breaking could be
clearly shown. The burden of this proof lies at the door of the .Sabbath-breaker. It

76 THE LOCOMOTIVE. [May,

cannot be denied that a large waste in labor and materials accompanies SaVjbath work.
Men who work on the Sabbath require some inducements to violate so clear made law —
an increase of wages, or abatement of the hours of work, or both. These range from 30
to 400 per cent, in excess of week-day work. But in addition to the direct loss in wages
and time worked, there is a further continued loss in the quality of work, which is
usually hastily and imperfectly performed.

Another loss is even more than this, arising from the debility of workmen employed
on the Sabbath, and which is carried through the work of the six days following.
Every such work of the Lord's day is a constant loss, both in its direct and reflex influ-
ences. It would not be just to charge managers of iron works with the whole sin of
Sabbath work, for it is well-known that too many of the workmen desire such work.
But the manager could readily abate very much of the work now performed on the Sab-
bath. The mode has been indicated for resting the furnaces on the Sabbath day. The
Bessemer converting works, blooming mills, rolling mills, with their associated plant, are
mainly at rest on the Sabbath day. A large amount of work, however, is done in their
repairs and renewals. It is plain that this can be abated. It will require investment in
keeping on hand a suflRcient stock of duplicate machinery, to replace breakages promptly
and to enable repairs to be made during the week. It is submitted that the excess of
wages paid and loss in work, would alFord a large interest on the capital required for
duplicate machinery for repairs. As the works close early on Saturday, sufficient time is
afforded to replace and repair the breakages and wear of ordinary work. That this can
be done,is just as clear as that the furnace can be rested. Sunday work in all depart-
ments of iron works is poor work. It is frequently followed with disastrous breaks. It
also induces a great waste by breakages in the neglect to repair them promptly under
the plea, " Oh, that can be fixed up next Sunday." Necessity of Sabbath work in any
department of iron making cannot be defended. If the furnace can be rested, all other
operations of iron manufacture can more easily be rested. There can be no conflict
of physical and moral laws, for both have the same source in one Creator.

It is confidently submitted that by Sabbath rest at iron works great saving would
follow. That a faithful eff'ort to rest on the Lord's day would reduce the expenses of
repairs and maintenance of machinery and appliances — secure more regular work, and
largely reduce " breakages." It would be followed by better work during the week —
more vigorous, clear-headed, and sustained. It is not even remotely implied, that the
iron works managers are " sinners before the Lord exceedingly." In many cases they have
had the Sabbath breaking sin handed down to them. All that can be urged is, that
they have not given this great question the attention its importance demands. On the
other hand, it is the glory of American iron works managers, that they have cherished
the material interest of their workmen with persistent care. They have planted a great
protecting shield in the tariff laws, on which the world may read in letters of gold :
" We desire it understood that we shall not enter into competition with European iron
managers on the basis of starving the workmen to make cheap products. Our men must
be well fed and cared for, with such wages as will enable them to educate their succes-
sors, making them more valuable workmen and better citizens — thus contributing to
material progress in iron making and to the perpetuity of our republican form of
government.

This position is deserving of much praise. But the Creator admonishes, " that men
cannot live by bread alone." Food and education are good, but man must be cultivated
in his entirety. He cannot attain his full degree of usefulness, until every element of his
being is cultured and brought into harmonious action. The moral qualities of the man
must be developed. He is a religious being. Just so long as the Creator's monitor
throbs its approval or disapproval in his heart, just so long must it be harmonized, or

1882] THE LOCOMOTIVE. 77

else the whole is discord. Christianity is the complement of manhood. It is cheering to
know that we are living in an age of material and moral progress. The clouds of sla-
very have been lifted. Polygamy totters in its mountain pastures. Intemperance is
being dismembered piece by piece. May we not hope that tlie managers of iron works
will consider this sin of Sabbath desecration, and plant before the eyes of the world, a
second moral protecting shield, on which shall be inscribed: "As for us and our
workmen, we shall endeavor to keep holy the Lord's day." " For the wages of sin is
death."' — Iron Age.

Standard Time for the World.

At the meeting of the American Society of Civil Engineers at Washington, D. C,
May 17th, an interesting report upon the subject of standard time was read by Mr. San-
ford Fleming of Ottawa, Canada. Mr. Fleming is the chairman of a committee appointed
by the American Society of Civil Engineers at its meeting in Montreal on June 15th,
1881, to take into consideration the question of standard time. At the annual meeting
of the society in Xew York last January, the committee made its first report, submitted
a scheme for the establishment of a prime meridian, and of uniform standard time, and
suggested the expediency of obtaining an expression of opinion upon the various points
which presented themselves from as large a number of practical and scientific men as
possible. This suggestion was approved by the societj', and the committee was author-
ized to take such steps as might be necessary to obtain information which would enable
it to report definitely at a future meeting. The committee prepared a series of questions
to cover the whole subject, and sent cojnes of it to a large number of jiersons throughout
the country who are practically interested in the question.

By the scheme referred to, it is proposed : —

Firist. — To establish one universal standard time, common to all peoples throughout
the world, for the use of railways, telegraphs, and steam-boats, for the purposes of trade
and commerce, for general scientific observations, and for every ordinary local purpose.

Second. — It is proposed that standard time everywhere sliall be based on the one
unit measure of time denoted by the diurnal revolution of the earth, as determined by
the mean solar passage at one particular meridian to be selected as a time zero.

Third. — The time zero to coincide with the initial or prime meridian to be common
to all nations for comjiuting terrestrial longitude.

Fourth. — The time zero and prime meridian of the world to be established with the
concurrence of civilized nations generally.

Fifth. — For the purpose of regulating time everj'where it is proposed that the unit
measure, determined as above, shall be divided into 24 equal parts, and that these parts
shall be defined by standard time meridians established around the globe, 15° of longi-
tude, or one hour, distant Irom each other.

Sixth. — It is proposed that standard time shall be determined and disseminated
under governmental authority ; that time signal stations be established at important cen-
ters for the purpose of disseminating correct time with precision, and that all the railway
and Ideal public clocks be controlled electrically from the public time station, or other-
wise kept in perfect agreement.

Seventh. — The adoption of the system in the United States and Canada would, ex-
clusive of Newfoundland and Alaska, have the effect of reducing the standards of time
to four. These four standai ds, precisely one hour apart, would govern the time of the
whole country, each would have the simplest possible relation to the other, and all would
have equally simple relations to the other standards of the world.

Finally. — It is proposed to have only one series of hours in the day, extending from

78 THE LOCOMOTIVE. [Mat.

midnight to midnight and numbering 1 to 24, without interruption, to number the
hours between midnight and noon (1 to 12) precisely as at present, and to denote the
hours between noon and midnight by letters of the alphabet.

To the series of questions which accompanied this scheme, the committee has re-
ceived hundreds of replies, and Mr. Fleming in his report to the society to-day, gave a
classified statement of their purport, as follows : Ninety-seven per cent, of all the writ-
ers approve the scheme. 76 per cent, express themselves as in favor of four standard
meridians in Xorth America, one hour or 15° apart. 6 per cent, favor two meridians,
and a small minority prefer one continental meridian. In reply to the question with
regard to a change in the notation of the hours of the day, a very large majority of the
committee's correspondents — 92 per cent, of the whole number — express themselves in
favor of counting from 1 to 24 consecutively. In conclusion Mr. Fleming said : " Upon
the replies received to its questions, the committee is fully warranted in reporting that
there is throughout the country a very strong sentiment in favor of establishing a system
of standard time, upon the basis of the scheme which the society now has under tonsid-
eration. The report of the committee was approved by the society, and resolutions were
adopted requesting Congress to take the initiative step, by endeavoring to establish a
prime meridian which shall be common to all nations."

Overloading Safely Valves.

The practice, which prevails extensively, of loading the safety-valves of steam boilers
beyond the proper limit is a most dangerous one, and cannot be too strongly condemned.
Cases are very frequent, where, by this means, old boilers, worn and thinned by
corrosion, are regularly worked at a much higher pressure than they were originally
intended for when new. There can be but one result of such a course, and that points
unerringly toward disaster. The wear and tear of a boiler so overloaded and over-
worked is vastly increased, so that little if any economy results from the practice. It is
true, that in times of great business prosperity, when every department of a manufactur-
er's establishment is driven to its utmost capacity, that the teoaptation to overwork a steam
boiler is very strong, still the practice is, under any circumstances, wholly inexcusable.
With most kinds of machinery the only result of overwork is simply the failure of the
machinery and the consequent pecuniary loss ; but with steam boilers the case is differ-
ent. Here the damage in case of accident is not confined to the boiler itself, or even
destruction of adjacent property, but human lives are almost invariably sacrificed. We
think everyone will agree with us when we say under no circumstances is the imperil-
ment of people's lives justifiable. Everything should be done that human knowledge
renders possible to make the use of steam perfectly safe.

The Hartford Steam Boiler Inspection and Insurance Company intends to deal fairly
with all its patrons, and always allows a pressure which the judgment of its inspector
deems safe, when boilers are placed under its care. It has no disposition or motive to
deal unfairly with anyone. Its inspectors are selected solely on their merits and capacity
to fulfill their duties intelligently ; consequently their judgment maybe relied upon as
far as it is possible to rely upon luftnan judgment in any given matter. When they fix
upon a certain definite jjressure for any given boiler that pressure may be considered to
be consistent with safety.

Now this company cannot afford to, and will not, insure a boiler for a certain pres-
sure and then have the weight on the saft\-valve increased at the will of the engineer
or owner of the boiler the minute the inspector's back is turned. This is frequently
done, as may be seen by reference to tlie Inspectors' Monthly Reports, piiblished in the

1882.] THE LOCOMOTIVE. 79

Locomotive. We wish it to be distinctly understood by everyone that this renders the
policy of insurance void, and that we cannot, and will not, be held responsible for dam-
agre caused bv accidents which occur under such circumstances. Cases have occurred
very recently where we have been obliged to cancel policies for the above reason. In
case of explosion under such circumstances the damage to the company is twofold. In
addition to the pecuniary loss involved, the judgment of the company is called in ques-
tion, and the matter is eagerly seized upon and spread far and wide for the sole purpose
of injuring its business. We have abundant proof in our possession that some of the
worst accidents that have occ»rred to boilers under our care have been brought about by
a violation of the conditions of the policy in this respect. We think any fair-minded
person will agree with us, that we are justified in canceling our policies where such a
state of things exists, botli for our own protection and for the purpose of putting the
responsibility where it belongs.

Notes and Queries.

C, Waterbury, Ct., asks : — How long will a superheating steam-drum last, when ex-
posed to a temperature varying from 500 to 1,200 degrees Fahr. ? The drum to be made
of wrought-iron, T. S. 50,000, | inches thick, 30 inches diam., double-riveted?

Ans. We are of the opinion that the drum would be rendered worthless the first
time it attained the temperature of 1,200 deg., which is a full red-heat. The tightness
of the joints would certainly be destroyed. Leaving the aliove questions out of consid-
eration, the iron would be rapidly oxydized by the action of the steam at such a high
temperature tliat the shell would probably be wholly destroyed in a few months. Cases
have occurred where the lining of steam chimneys have been reduced from |" to ^g" in
fourteen months. This, however, is an extreme case.

A., Hartford, Ct.. inquires: — Why will an internally fired boiler, such as a round
water-front for example, when set in brick-work, always leak on the vuder side when the
products of combustion are led directly to the chimney after passing through the flues,
or when they are returned over the top of the shell ?

Ans. The leakage is caused by unequal expansion of the top and bottom of the
shell, which is due to diff'erencc of temperature between top and bcttom, the top being
much the hotter in either case. This difierence of temperature is due to the imperfect
circulation of the water in the boiler, owing to abs(nce of heat on the under side of the
shell. The difficulty may be remedied by returning the heat along the under side, as is
usually done in the case of drop-flue boilers. Boilers designed to be used in this way,
wonld be improved by double-riveting the girth seams, and caulking inside and out.

J. H., Boston. Mass., inquires: — Is a six inch tube as effective as a stny, as a three
inch tube ? In other words, if I have in one case a boiler-head, say CO" diam., containing
G4 three inch tubes, and in another case a head of the same size in whicli are 32 six
inch tubes, which head would be the more eflectively stayed ?

Ans. The one with the three inch tubes. A head containing 64 — 3" tubes, would
hold only IG — 0" tubes, not 32. A C'tube Avill sustain twice as much as a 3" tube, but
there can be only one-fourth, as many in a given area; consequently, this would reduce
the staying power o?(e-/(a//'. In addition to this, the area between tubes on which the
steam pressure acts, is twice as great in the case of the 6" tubes, as in the case of the
3" tubes; thus there is a further reduction of one-half in the staying power. Hence, it
is evident that you have twice as much pressure to sustain in one case as you have in the
other, and only one-half xhc power to resist it; therefore, the effective staying power with
G" tubes is only one-fourth what it ia with 3" tubes. .' *"

W. S., Brooklyn, N. Y., inquires: — Is there any simjjle rile for determining the
thickness of flat, unstayed, cast-iron boiler heads?

Ans. Yes. the following: '\/_^1JLF= thickness; in Avliich D denotes the

^ 24.00U
diam. of the head, and P, the required safe-working pressure.

THE LOCOMOTIVE.

[May.

Incorporated
1866.

Charter Per-
petual.

Issnes Policies of InsnraDce afler a Carefnl Inspection of tlie Boilers,

COVERING ALL LOSS OR DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

ARISING FROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full infonnation concerning the plan of the Company's operations can be obtained at the

co3sd::E».A.i?rir's oifp^iozej, H-i^iaTiFOiF^iD, consmsr.

Or at any Agency.

J. M. ALLEN, Prest. W. B. FRANKLIN, Vice-Prest. J. B. PIERCE, Sec'7.

Boa<r<l of Directors :

J. M. ALLEN. PreBident.

LUCIUS J. HENDBE. Prest. .(Etna Fire Ins. Co.

FRANK W. CHENEY, Treas. Cheney Brothers Silk

Manufacturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Amer. Nat. Bank.
RICHARD W. H. JAR VIS, Prest. Colt's Fire Arms

Manufacturing Co.
THOMAS O. ENDERS, of .^tna Life Ins. Co.
LEVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Qkn. WM. B. FRANKLm, Vice-Prest. Colt's Pat. Fire
Arms Mfg. Co.

GEO. CROMPTON, Crompton Loom Works, Wor-
cester.

Hon. THOS. TALBOT, Ex-Governor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manufacturer, Provi-
dence, R. I.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. parry, of Baldwin Locomotive Works,
Philadelphia.

How. HENRY C. ROBINSON, Attorney at Law.

GENERAL AGENTS. CHIEF INSPECTORS.

OFFICES.

THEO. H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKIM,

W. S. Chamberlin,

J. L. SMITH,

H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

R. K. McMURRAY,
WM. G. PIKE,
JOSEPH CRAGG,
WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN,
J. H. RANDALL,
A. C. GETCHELL,
J. S. WILSON,

New York City.
Philadelphia.
Baltimore.
Boston, Mass.
Providence, R. I.
Chicago, III.
St. Louis, Mo.
Hartford.
Bridgeport.
Cleveland.

CiNOINHATI.

OflBce, 285 Broadway.

" 430 Walnut St.
" 10 So. HoUiday St.
" 10 Pemberton Sq're.
" 15 WeyboBset St.

" 132 La Salle St.

" 404 Market St

" 218 Main St.

" 328 Main St.

" 246 Superior St.
" 63 West Third St.

afe

0t0ni0tte.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series — Vol. III.

HARTFORD, CONK, JUNE, 1882.

No. 6.

Proportions of Riveted Joints.

Last month we showed various proportions for single-riveted lap joints ; in this num-
ber we give the double-riveted joints from the same sources, with a comparison of their
eflSciencies. One of the commonest forms of joint is shown in Figs. 1 and 2. Here the

Fig. 1.

Fig. 2.

pitch and rivet diameter are the same in both the single and double joints. In the
single riveted joint the strength of plate at joint as compared with the solid plate is

THE LOCOMOTIVE.

[June,

? II _ 61 per cent.; and the strength of the rivets as compared with the solid plate is

= 77 per cent., from which it will be seen that the rivets are much the stronger.

^47937
.2X ,»

This being the case, what use is it to put in another row of rivets and make a double-
riveted jotnt without increasing the section of tlie plate ? It merely adds to the expense
of the boiler without in the least increasing its strength or durability. Purchasers ot
boilers who specify double-riveted joints would do well to look to this point and insist

upon reform.

"VVe give the proportions as we find them.

Fig. ?.
Fi-. 3. Plates Nos. 5, 4, 3, 2, and 1. Rivet holes, \\" diam. Pitch of rivets = 2*".
St Jeugth of plate at joint = ^-^^=^ = '^^ 1^ of solid plate.
Strength of rivets at joint No. 5 plate = ^^^^^ = 135 ^ of solid plate.
Strength of rivets at joint No. 4 plate = |^g|| = 125 % of solid plate.
Strength of rivets at joint No. 3 plate = '^^^ = 115 f. of solid plate.
Strength of rivets at joint No. 2 plate = g|^, = 104 f. of solid plate.
Strength of rivets at joint No. 1 plate = f'^ = 99/. of solid plate.
The stren-th of the rivets is out of all proportion to the strength of the plate. The
pitch should be increased, and the diam. of the rivets reduced

Fig. 4. Plates, 2, 1, 0, and 00. Rivet holes f diam. Pitch of nvets _ 2i .
StLgth of plate at joint = ^^^ = '^0,^ of solid plate.
Strength of rivets at joint No. 2 plate = '^^^^ = 124 /. of solid plate.
Strength of rivets at joint No. 1 plate = '^^ = 1 18 ^ of solid plate.
Strength of rivets at joint No. 0 plate = -^^^ = 104 ^ of solid plate.

1883.]

THE LOCOMOTIVE.

strength of rivets at joint No. 00 plate == ^^^^ = 99^ of solid plate.

Fig. 4.
In the above examples the pitch is the same, and in the second example the joints
would be better proportioned if the rivet holes were H" ^iam. If one should ask the
man who uses 2^" pitch in No. 00 plate why he didn't use a larger pitch and get a
stranger ioint he would probably say he could not make a tight joint if he did. And
vet the first man uses the same pitch (2^") in plates only .22" thick or less than two-
thirds the thickness, and he has no difficulty in keeping the joints tight. Surely one or
tlie other must be wrong.

Fig. 5.
Fig. 5. Plate ^" thick. Rivet holes f diam. Pitch of rivets = 2f' .
Strength of plate at joint = '

2.5
44179x2

Strength of rivets at joint = 2 5 x 3125

= 70 ^ of solid plate.
= 113^ of solid plate.

THE LOCOMOTIVE.

[June,

Fig. 6.

Fig. 6. Plate f^" thick. Rivet holes if" diam. Pitch of rivets = df.

StLgth of p^.ate at joint = ^^^^=^ = 75 ^ of solid plate.

Strength of rivets at joint = gl^^g = 102^ of solid plate.

The above is the best proportioned double-riveted joint we have seen thus far.
Those who maintain that a tight joint cannot be made with a wide pitch may perhaps
-be consoled by the statement that the above is the proportion used by the largest and
,most successful builders of locomotives in this country. As a matter of fact the secret ot
rthe whole thing is this : Do the work in an intelligent manner. Do not depend on the
.hammering which the rivet receives to bring the plates together. Press your plates
tightly together and hold them while the rivet is being driven.

Fir. 7.

Plates ^%" and f" thick.

Fig. 7.
Rivet holes |" diam. Pitch of rivets = 2|' ,

1882.]

THE LOCOMOTIVE.

2.5— .75 ^ 70 6^ of solid plate.

Strength of plate at joint = — 275

Strength of rivet at joint ^V' P^^^e = ^7^3^^3105

Strength of rivet at joint f " plate = ^|^^ = 94 ^ of solid plate

44179x|_ _ j^3 ^ of goii^i plate.

Fig. 8.
Fig. 8. Plates f" thick. Eivet holes H" ^iam. Pitch of rivets = 2>2".
Strength of plate at joint = ^-^^=^ = ^U ^ °f ^^^^^ P^^^e.
Strength of rivets at joint = |^^ = 1 H ^ of solid plate.
A difference of over 50 per cent, in strength between rivet and plate.

Fig. 9.
Fif. 9. Plate fy" thick. Rivet holes i" diam. Pitch - 2|".

THE LOCOMOTIVE.

[JCNE,

2 7'5 875

Strength of plate at joint = ' ^ ^- = 68 fc of solid plate.

Strength of rivets at joint = ~,^^^.^,L = 100 ^c of solid plate.

Fig. 10.

Fio-. 10. Plates, f", Yg", and ^" thick. Rivet holes -J |" diam. Pitch of rivets =2^".

o =5 Rl'^o

Strength of plate at joint = ^ ' ./. " = 67^ </c of solid plate.

51849 x'*
Strength of rivets at joint in |" plate ■= \ . ^^^ =110,^ of solid plate.

51849x2
Strength of rivets at joint in fg" plate = ^ . j^ = 95^ of solid plate.

51849 x2
Strength of rivets at joint in h" plate = ' ^^ = 83^ of solid plate.

Fig. 11.

Fig. 11. Plate f thick. Rivet holes, |-|" diara. Pitch = 2|" .

1882.]

THE LOCOMOTIVE.

strength of pl.te at joint = ^^^^4^ = 70 ^ of solid plate.

Strength of rivets at joint = '-^^^ = 75 ^ of solid plate.

Fig. 12.

Fig. 12. Plate f thick. Rivet holes i^" diam. Pitch of rivets = 3".

Strength of plate at joint = 'tz^ = 69 fc of solid plate.

Strength of rivets at joint = '^^^ = 93^ of solid plate.

Next month ^ve shall submit what we think are the proper proportions for single
and double-riveted joints, and invite a candid and thorough criticism from all boiler-
makers and others interested in the matter.

Inspectors' Reports.

Apuu-, 1882.
Below is given the usual summary of the work of the Company's Inspectors for the
month of April last. From it we learn that the number of visits of ^-^^^f^^^tl
was 2009 during which a total of 4.533 boilers were exammed. The number inspected
both ext;rnallv and internally foots up 1762, and 412 were tested ^y hydrostatic pres-
sure. The number of boilers condemned as being unfit for further use was 57. Below
is given the usual summary of defects noted:
Nature of defects.

Cases of deposit of sediment,

Cases of incrustation and scale,

Cases of internal grooving, - - - '

Cases of internal corrosion, - - - ■

Cases of external corrosion, - - - "

Whole number. Dangerous.

263 - - 34

351 - - 30

22 - - 11

130 - - 34

134 - - 30

88 THE LOCOMOTIVE. [JraE.

Broken braces and stays, . . - - -

Settings defective, ..-.--
Furnaces out of shape, . . . . .

Fractured plates, ...--.
Burned plates, .-.--.

Blistered plates, ......

Defective riveting, .-.---
Defective heads, .-.---

Leakage at tubes, ------

Leakage at seams, ------

Water-gauges defective, - - - - -

Blow-out defective, ------

Cases of deficiency of water, . - - -

Safety-valves overloaded, -----

Safety-valves defective in construction,

Pressure gauges defective, . - - - -

Boilers without pressure gauges, . - - -

Total, - - 2,925 - - 569

118

146

233

459

304

174

158

A New Galvanometer for Powerful Currents.

A novel form of galvanometer for the measurement of intense electric currents was
recently presented to the French Academy of Sciences by MM. Zerquem and Damien.
It consists essentially of a magnetic needle pivoted at its middle like the ordinary tan-
gent galvanometer needle, but the conductor conveying the current in its vicinity, instead
of being in the form of a coil of wire round the needle, is constructed of a stout band of
copper, so that the instrument has practically no internal resistance, and it passes under
the needle and parallel with it when in the zero position. Several of these bands (there
were six in the specimen exhibited) run below the needle through a block of insulating
wood, and parallel to one another, this block of wood carrying the conductors, and the
needle is mounted on a vertical stem of wood planted in a socket, so that it can be
turned round by hand to any angle, and the current can be led to any band desired by
means of vertical bands of copper, and a contact screw. The mode of using the appara-
tus consists in sending the current through one or other of the bands according to its
degree of strength, and tliereby getting a deflection of the needle. The block or bowl
of the compass is then turned round until the needle points to the zero of the scale.
The current is then interrupted, and the deflection angle of the needle read oflF. This
deflection gives the rotation of the bowl, and the sine of the angle is proportional to the
intensity. The several bands give the apparatus a certain range of power, and if the
current is too strong for that nearest the needle it can be sent through one further off.
CoeflScients for finding the relative powers of the bands can be found by experiment.
Moreover, for each band a curve or table of intensities corresponding to given deflection
can be calculated. Such an apparatus will measure the current of a dynamo-electric
machine without the use of shunts; and it appears to be very simple and eflfective.
— Engineering.

The reports for 1881 of the Miirlcischer Verein zur Prufung und Ueberwachung von
Dampfkesseln in Frankfurt a. Ober, and also that of the Verein zur Ueherwachung der
Dampfhessel mit dem Sitz in Hannover, have just been received. They contain much
information of a valuable character relating to the proper management of boilers.

1882.] THE LOCOMOTIVE. 89

$$]$

HARTFORD, JUNE, 1882.

The Locomotive on the Track.

A correspondent signing himself X has been taking up considerable space of late in
the Manufacturers' Gazette, on a subject which apparently he is not veiy familiar -with,
or has an unfortunate infelicity in expressing his views. In a recent number he felt
called upon to criticise our editorial on the experiments of Mr. Lawson, making wild
assertions about our " being oflf the track," contradicting ourselves, etc. We have to say
simply that the views which we expressed are the same that we have entertained and
given expression to from the first. "We quote from an article which we published in the
Locomotive in 1868, as follows: ''Now if water subjected to high heat is confined, as
in a steam boiler, its temperature may be increased almost indefinitely. For instance, in
a boiler steam may be raised to a pressure of one hundred and forty pounds, which
would be at a temperature of three hundred and sixty degrees, or one hundred and
forty-eight degrees above the temperature required to produce steam, with the water sur-
face open to atmospheric pressure. Now, if when the water has been so heated the pres-
sure is removed, the water cannot remain in its original condition, as water merely, but
a part of it becomes immediately converted into steam ; and. if the pressure is excessive
(or very high) and suddenly removed, it will cause a tremendous blow to be discharged
upon the sides of the boiler sufiicient, no doubt, not only to extend any existing rupture
but to completely rend the boiler in pieces. There is reason to believe that steam alone,
striking at a great velocity upon a solid surface, can discharge a violent blow, in addition
to whatever effect it may produce by its pressure when at rest. Many steam users and
theorists formerly contended that this percussive action of steam was suflBcient to account
for the most destructive boiler explosions ; but more recent investigations have led engi-
neers to look beyond this for an explanation. The following letter from Mr. D. K.
Clark to the editors of the Mechanics'' Magazine gives his views on the subject, based
upon careful investigation :

"'Gentlemen: I have, within the last few months, given some attention to the sub-
ject of boiler explosions — their cause and their rationale. I observe, in the discussions
that have appeared in contemporary papers, that the percussive force of the steam sud-
denly disengaged from the heated water in a boiler, acting against the material of the
boiler, is adduced in explanation, and as the cause of the peculiar violence of the result
of explosion. Now, gentlemen, a little calculation would show that the percussive force
of steam is not capable of causing such destructive results as are occasionally produced ;
and I beg leave to suggest that the sudden dispersion and projection of the water in the
boiler against the bounding surfaces of the boiler is the cause of the violence of the
results, the dispersion being caused by the momentary generation of steam throughout
the mass of the water and its efibrts to escape. It carries the water before it, and the
combined momentum of the steam and the water carries them like shot through and
amongst the bounding surfaces, and deforms or shatters them in a manner not to be
accounted for by simple over-pressure or by simple momentum of steam.

" ' Your obedient servant, D. K. CLARK.' "

We have copied only a portion of the article which we wrote in 1868, but sufficient to
show that our views have undergone no change. Our publications since have maintained
the same views as against the dangerous "mysterious agency" theory, which comes to
the surface now and then. It is fair to presume that X has been a diligent reader of the

90 THE LOCOMOTIVE. [Junk,

publications of this company, and that what few sound views he gives expression to
have been derived from that source. He seems to be a tyro at the business, and proba-
bly had not commenced his investigations when the above article was written — lie may
not have been born. In a Locomotive article, written some time ago, on boiler explosions,
we summed up their causes under four heads, viz., lad material^ faulty m type, had work
in construction, and inefficiency and carelessness in management. X desires to know under
which of these four heads Mr. Lawson's theory should be classed. If this inquiry came
from some sources we might be surprised, but nothing that X says surprises us. If he
will read carefully our report in the April Locomotive, commencing on first page, he will
be able to understand how Mr. Lawson's experiments were conducted. It will be seen
that as the pressure increased the safety-valve was opened at intervals of from two to six
minutes. The object was to hurst the hoiler, and observe the conditions under which it
"let go." It was run up to excessive pressures. This was perfectly proper for ^Mr. Law-
son to do. His work was experimental. He did not aim to run the boiler carefully or
safely. Suppose a manufacturer should introduce the same practice into the boiler-house
of his mill — run the boilers up to near their bursting pressure, erect a "bomb proof" to
protect the man in charge, provide a cord to enable him to raise the safety-valve at inter-
vals of three or five minutes as the pressure increased, would that be regarded as safe
practice ? It would he condemned at once as the height of carelessness — criminal carelessness
in management. If X had fully comprehended this subject, he would hardly have asked
so foolish a question. He is evidently in the fog of " super-heated water," which, judg-
ing from his expressions, he fails utterly to understand. Investigations in this direction
intelligently made are valuable contributions to the literature of the subject. Experi-
ments on the Donny theory, as relating to boiler explosions, were made at the Massachu-
setts School of Technology several years ago, and the results, instead of furnishing any
explanation of the causes of boiler explosions, exploded the theory itself. Such experi-
ments, made by such men as the professors of this school of science, and their conclu-
sions, have weight and are valuable. But the value of X still remains an unknown quan-
tity.

Riveted Joints. /

The articles on the strength of riveted joints which are being published in the
Locomotive are based upon the rules recommended by the English Board of Trade, and
will be found in their "Manual of Instructions as to the Survey of the Hull, Equipment,
and Machinery of Steam Ships Carrying Passengers." There are two rules: First, one
for ascertaining the percentage of plate at joint as compared with the solid plate; and
Second, one for ascertaining the percentage of strength of rivets as compared with the
solid plate.

The formulae are thus :

(Pitch — Diameter of rivets)

(1)

Pitch

(Area of rivets X No. of rows of rivets)

i . . (3)

(Pitch X thickness of plate)
Having ascertained the results of these two problems, the smallest of the two per-
centages must be accepted as the maximum strength of the joint, and should be used in
calculating the safe working pressure of the boiler. These rules were adopted by the
Philadelphia Commission recently appointed to revise the ordinance regulating the
inspection of steam boilers. The application of these rules to many of the joints of
boilers now in use and being constructed will show that the greatest possible strength of
joint is rarely attained. The size and pitch of rivets should be in such proportion to

1882.J THE LOCOMOTIVE. 91

the thickness of plate that the results of the two problems shall be the same.
Then we have the strongest form of joint attainable. We shall show in these articles
what the proportions are for the strongest joint. There is an aversion on the part of
many boiler-makers to increase the pitch beyond their usual practice from the fear that
a tight joint cannot be secured. We believe, however, that some slight changes can be
made that will secure a stronger joint and at the same time a tight one.

The Hon. William S. Slater, of Providence, R. I., died May 28, 1882, in that city,
aged sixty-six years. Mr. Slater was prominently connected with the manufacturing
interests of Rhode Island. He was the son of John Slater. His ancestors came to this
country in 1790, and erected the first cotton-mill in America, at Pawtucket. Mr. Slater
was a much-esteemed citizen of Providence. His gifts to the Rhode Island Hospital,
Brown's University, and Free Public Library, were munificent. He had been for many
years a member of the Board of Directors of the Hartford Steam Boiler Inspection and
Insurance Company.

"X"lraordinary.

It is a sad sight and a sorrowful commentary on the alleged perfection of the human
brain (?) to see a man set out to demonstrate the truth of the views which he entertains
on a certain subject, and become so thoroughly mixed up before he gets through that
he entirely loses sight of his original ideas. The spectacle is made more especially mor-
tifying when the aforesaid man suddenly wakes up, and, finding himself advocating his
opponent's views, says that those were his views all along, and very deliberately accuses
his antagonist of trying to switch on to his track. There may be no analogy between the
two cases, still it reminds me very forcibly of the story about the drunken man who was
one day riding upon a horse-car, and, being somewhat confused, fell over the tail-board
of the car into the mud. After floundering around awhile he was finally helped up, and
indignantly demanded why the car ran off the track. Upon being informed that the car
had been on the track all the time, and that there had been no collision, he confidentia ly
informed the bystanders that "if he had known that he wouldn't got off."

Such seems to be the plight into which X has fallen. Originally setting out to
prove that superheated water was the sole cause of ])oiler explosions, he speculates
along in a desultory way for several months in a series of articles entitled, "Why Boilers
Burst." In this series of articles (?) I have looked in vain for any very decided reference
to boiler explosions; but, after he has proved in a very labored way, by dint of using
many " therefores " and "hences," that the presence of a thick coating of scale on the
internal surfaces of a boiler is an efficient safeguard against over-heating the plates, and
also that it takes longer and requires more heat to get up steam from water after it begins
to boil than it does from the same water when it is cold, he discovers that experiments
made to determine the elfect of the shock which is produced by suddenly opening a
large valve in a boiler under high pressure, illustrates exactly what he has been trying to
demonstrate. The funny part of the matter consists in his suddenly straddling this and
calling it "his theory"; and when he finds that the Locomotive thinks much harm may
be done to a weak boiler in this manner, he says that he "is glad that the Locomotive
has been converted to his view, even though it be an eleventh hour repentance." If X
will be so good as to refer to the Locomotive for January, 1868, he will find the same
matter discussed there in a manner which cannot fail to convince him that the Locomo-
tive is not "off the track," neither is it "switching with some difficulty on to a new
line," as he alleges. This must be all the more distastetul to him by reason of his
emphatically-expressed aversion to anything bearing upon boiler explosions " formulated
more than twelve years ago." He may also perceive that the only person in any imme-

92 THE LOCOMOTIVE. [June,

diate danger of getting "left" is the aforesaid man who fell over the tail-board into the
mud.

Now, why doesn't X stick to his original theory and sink or swim with it, and not sud-
denly throw it overboard and grasp at one propounded and discussed in the' Locomo-
tive more than fourteen years ago? Why doesn't he confine his arguments to proving
that water really can be superheated in a steam boiler, and that this superheating may
be brought about by merely shutting off" the steam, as he asserts in his first paper? That
he has changed his views may readily be seen. Referring to my statement that he evi-
dently considered water heated above 212° Fahr., under any circumstances, to be super-
heated, he says: "I adhere to my original statement, that, under ordinary conditions,
with the atmospheric pressure of fifteen pounds to the square inch, these steam bubbles
are not perceptible until the water arrives at a temperature of 212^; but when we repeat
this test under a vacuum we observe that ebullition occurs at a far lower temperature,
showing that, with the removal of the pressure on the water, steam is generated with a
lower degree of heat, and proving, likewise, that the greater this pressure, the greater
the degree of heat the water must absorb to produce a given steam force. This explains
the phenomenon of superheated water, or water raised above 212° without making
steam."

On the contrary, it does not "explain the phenomenon of superheated water." It
merely illustrates what every one is familiar with, viz., the dependence of the boiling
point on the external pressure, and has not the remotest connection with the phenom-
enon of superheated water. Moreover, it is not X's "original statement," nor does it
agree with his original statement in any particular. It is strange X cannot quote his
own language correctly, but such is the lamentable fact. His "original statement"
appears in ihe Manufacturer s Gazette of January 28th, and reads exactly as follows:
"Now let steam be cut off" from the engine. What is the result? The steam keeps on
forming, and the globules accumulate until the pressure they exert is equal to the pres-
sure of the fire. The two forces being equal, action ceases. . . . But there is a subtle
force at work all this while. It is true that steam is not being formed actively; hit the
heat is entering thexcater^ and is absorbed hy it.''"'

Now if any one can discover any resemblance between the above two " original
statements," they are justly entitled to a large reward. The latter one is the true explana-
tion of superheated water, not the former, which X avers to be his "original" explana-
tion. But I showed conclusively in the April Locomotive that it was impossible for the
water to attain such a state in a steam boiler, and X has not yet disputed it. As he stu-
diously avoids any discussion of this point, which is the only question on which I have
taken issue with him, I incline to the belief that this Jumbo of modern steam engineers
is trying to crawl under the tent to get out of the clown's way !

But as he evades discussion of the point at issue and seeks to create a diversion by
" catching on " to the Locomotive's theory, I will take leave of him by recalling one
paragraph which he has written, which well illustrates the keenness of his intellectual
vision and broad grasp of his subject generally. In the Gazette of May 6th he says:
"In 1874 I examined a steam boiler which had been in use for some twenty years. ... I
found the flues at the back end of the boiler so corroded as to leave a mere shell only, a
slight How upon which with a small hammer was sufficient to produce a bi"eak. . . . Now,
will the insurance companies inform me at what stage of its existence the hammer test
would have condemned that boiler ? "

Probably the inspectors, and all others who know what the hammer test is, will
appreciate the sublime ignorance displayed by asking the above question after making
such a statement. The guilelessness displayed is about equal to that of the man who
wanted to know what time the three o'clock train started for Podunk !

In conclusion I would caution X against biting into that " literary sandwich " too
recklessly, lest he find it too hard for his teeth.

H. F. S.

1882.] THE LOCOMOTIVE. 93

The Blue Process of Copying Tracings.

As Ave have had several inquiries recently in regard to the best method of copying
tracings by what is known as the " blue printing process," we will give a bi'ief descrip-
tion of the method employed by us ; we do not say it is the best, but it certainly is as
simple as any other, and has always given us perfect satisfaction.

The materials required are as follows : —

1st. A board a little larger than the tracing to be copied. The drawing-board on
which the drawing and tracing are made can always be used.

2d. Two or three thicknesses of flannel or other soft white cloth, which is to be
smoothly tacked to the above board to form a good smooth surface, on which to lay the
sensitized paper and tracing while printing.

3d. A plate of common double-thick window glass of good quality, slightly larger
than the tracing which it is wished to copy. The function of the glass is to keep the
tracing and sensitized paper closely and smoothly pressed together while printing.

4th. The chemicals for sensitizing the paper. These consist simply of equal parts,
by weight, of Citrate of Iron and Ammonia, and Red Prussiate of Potash. These can be
obtained at any drug store. The price should not be over 8 or 10 cents per ounce
for each.

5th. A stone or yellow glass bottle to keep the solution of the above chemicals in.
If there is but little copying to do, an ordinary glass bottle will do, and the solution
made fresh whenever it is wanted for immediate use.

6th. A shallow earthen dish in which to place the solution when using it. A com-
mon dinner-plate is as good as anything for this purpose.

7th. A brush, a soft paste-brush about 4" wide, is the best thing we know of.

8th. Plenty of cold water in which to wash the copies after they have been exposed
to the sunlight. The outlet of an ordinary sink may be closed, by placing a piece of
paper over it with a weight on top to keep the paper down, and the sink filled with
water, if the sink is large enough to lay the copy in. If it is not, it would be better to
make a water-tight box about 5 or 6 inches deep, and 6 inches wider and longer than
the drawing to be copied.

9th. A good quality of white book -paper.

Dissolve the chemicals in cold water in the following proportions : — 1 ounce of cit-
rate of iron and ammonia, 1 ounce of red prussiate of potash, 8 ounces of water. They
may all be put into a bottle together and shaken up. Ten minutes will suffice to dis-
solve them.

Lay a sheet of the paper to be sensitized on a smooth table or board; pour a little
of the solution into the earthen dish or plate, and apply a good even coating of it to the
paper with the brush; then tack the paper to a board by two adjacent corners, and set
it in a dark place to dry ; one hour is sufficient for the di*ying; then place its sensitized
side up, on the board on which you have smoothly tacked the white flannel cloth; lay
your tracing which you wish to copy on top of it; on top of all lay the glass plate,
being careful that paper and tracing are both smooth and in perfect contact with each
other, and lay the wiiole thing out in the sunlight. Between eleven and two o'clock in
the summer time, on a clear day, from G to 10 minutes will be sufficiently long to expose
it ; at other seasons a longer time will be required. If your location does not admit of
direct sunlight, the printing may be done in the shade, or even on a cloudy day ; but

from one to two hours and a lialf will be required for exposure. A little experience will
soon enable any one to judge of the proper time for exposure on different days. After
exposure, place your print in the sink or trough of water before-mentioned, and wash
thoroughly, letting it soak from 3 to 5 minutes. Upon immersion in the water, the
drawing, hardly visible before, will appear in clear white lines on a dark blue ground.
After washing, tack up against the wall, or other convenient place, by the corners to dry.
This finishes the operation, which is very simple throughout.

94 THE LOCOMOTIVE. [June.

The Effect of Extravagant Promises.

There is a somewhat familiar story of a man who upon estimating at the end of the
week the probable results of adopting all the "improvements" offered during the preced-
ing six days — improvements all looking to the saving of fuel in connection with his
engine and boiler — found that so far from buying any more coal he could open a coal-
yard, with reasonable prospects of supplying a fair trade. Whatever of truth there may
be, literally, in this story, it is entitled to the legend — " Founded on fact."

In view of the general increase of knowledge in matters pertaining to steam engi-
neering, it might with reason be supposed that extravagant assertions of prospective
savinof by the use of new devices, or by the re-employment of ancient contrivances, would
be less frequent than when there was a good deal of excusable ignorance in relation to
such matters. That is, this ignorance might be taken as an excuse why the inventor
should, if quite honest in his intention, deceive himself, or if not entirely sincere, should
attempt to deceive the purchaser.

The possibilities of the use of coal, in connection with the steam engine, according to
known methods, are made reasonably plain to those who read, or inquire, notwithstand-
ing which there is apparently no end of those who are anxious to agree to reverse all
known laws, by means which it is apparent contemplate no addition to existing knowl-
edofe of the subject. Instead of decreasing, the list of wonderful steam motors and re-
markable appliances that save considerably more than is wasted, were probably never so
numerous as just now.

No exception can be taken to those who ^look to doing more work — in the steam
eno-ine for instance — for less money. On the contrary, any one who accomplishes a
desired end in this direction, or even who honestly attempts its accomplishment, is in a
plain sense a benefactor. There is no trouble with what is accomplished, but rather
in the fact that the exaggerated statements of what is to he accomplished, serves the end
of preventing the trial and probable adoption of really valuable devices. A wise man
with a few hundred dollars puts it into some institution that can afford to pay the inter-
est it agrees to pay, rather than invest it with some one who offers 25 per cent. With
t^qual reason the purchaser of mechanical devices inquires as to the possibility of the
results talked of, and finding them impossible, sets the vender down as a fool or knave,
exactly which making no difference in the consequences.

The mistake made in this respect, and it is a mistake that often results disastrously
to the inventor or introducer, is that it is necessary to tell a large story to secure atten-
tion, while the fact is, that no one likes to be approached as if devoid of ordinary intelli-
gence. In effect, extravagant assertions of this kind made to those, who, however
limited their specific knowledge of the subject may be, are yet well enough acquainted
with it in a general way to recognize their absurdity, have much the effect of intensely
qualified expressions of any sort; that is, they discredit whatever of truth there may be
in the entire statement.

We noticed recently in a circular of a new valve gear, with which it is proposed to
displace an extensively-used and reasonably-economical type of cut-off gear, a claim —
made particularly prominent — of a saving of the new over the old of 50 per cent. For
all we know to the contrary, there are points of merit in the new arrangement that ought
to bring it into immediate general use. If this is true, it is a pity that it should go
seeking public favor handicapped with such an extravagant claim. The class of men
with whom this is to find favor particularly, know that it is impossible that it should
bring about any such saving; and it would seem that no better plan, not to have it con-
sidered, could be devised. As considerably better (?) than this, the result of the fuel
economy of using a device in connection with a locomotive, a device which has for its
principal object the bringing about of more cleanliness and hence comfort on the train,
is given as more than 70 per cent. Such statements are simply absurd on their face, and

1882] THE LOCOMOTIVE. 95

the wonder is, that it is not quite apparent that they go far to neutralize anything of
good there may be in the arrangement.

The writer remembers a few years ago, being applied to by a party — a stranger — to
examine a grate-bar for a boiler furnace, and, if thought well of, to give the exhibitor a
note that might possibly assist him in making a beginning in the locality. It was
purely a matter of good-will that led him to accompany the inventor to an establishment
for the purpose of introducing him to the engineer — a man who had grown old in the
business, and whose word would be sufficient in the matter of its adoption, or at least
its trial.

The engineer was favorably impressed, and, although using what he considered the
best grate of which he knew, was quite determined to give the new grate a trial, until in
an unfortunate moment the inventor sacrificed all possibility of his doing so, by assert-
ing that it would save 30 per cent, in fuel. The extravagance of the claim, perhaps in
its effect heightened somewhat by the covert insinuation that thirty years of experience
had only been sufficient to educate him up to waste 30 per cent, of the coal, efl'ectually
settled the grate-bar, so far as that party was concerned.

As previously intimated, such assertions are entirely uncalled for, and always work
to the detriment of the party making them. As a rule, purchasers are satisfied with a
reasonable saving, and are more inclined to meet a seller who only promises what is at
least possible, than one who promises impossibilities. Beyond the point of the selling
of something of the kind referred to, the seller can never get so good a recommend as
that of having it do more than he promised, nor so poor a one as the having it do
materially less.

The efiect of extravagant promises is entirely adverse to the interest of the seller —
in the first place as operating against the probability of his selling what he has to dis-
pose of, and in the second place as resulting in dissatisfaction, should he succeed in
selling. — American Machinist.

Notes and Queries.

W. L. G., Hamilton, N. Y., inquires: "What is the best method of removing scale
collected in feed-pipe? Pipe runs through front head of boiler over furnace, no circu-
lating pipe inside. Where does one apply for engineer's license? What is the best
weekly paper to take to gain information regarding engines and boilers?"

Ans. (I) Try solvents dissolved in the feed water. If the scale is a lime scale, soda
ash or tannic acid will be found useful. If this fails you had better take the pipe out
and remove the scale by mechanical means. (2) In the cities of New York and Brooklyn,
to the Boiler Inspector's Department, at Police Headquarters. In the smalkr towns we
believe no license is required. (3) For sources of information regarding engines and
boilers see answer to W. T., below. The Boston Journal of Commerce, the American
Machinist, and Mechanics are all good papers for an engineer to take.

E. L,, St. Louis, Mo. Your suggestion is a good one, but it lies outside of our spe-
cialty.

From W. T., Cambridge, Mass. : " What are the disadvantages of the Compound
Tubular Boiler other than not being able to get to lower shell to clean it, and its prim-
ing ? What is a good elementary book on steam-boilers and engines ? "

Ans. (1) There are no other especial disadvantagesif the boilers are well constructed
of good material. (2) The best work on boilers is Wilson's Treatise on Steam Boilers,
published by Crosby, Lockwood & Co., of London. For works devoted more particu-
larly to engines we can recommend Thurston's Rise and Growth of the Steam Engine
King's Practical Notes on the Steam Engine, and Forney's Catechism of the Locomotive.
If you are already familiar with the construction and practical operation of different
types of engines, we would advise you to read Cotterill's Steam Engine Considered as a
iltat Engine and D. K. Clark's Fuel, its Combustion and Economy. All of the above may
be obtained of any bookseller.

D. W. C. H., Willimantic, Conn., asks: "What is the proper way to leave a com-
mon tubular boiler which is to remain out of use during the summer, it being used as a
heating boiler in the winter ? Should it be left full of water, or empty ?"

Ans. Blow the boiler off while the setting is somewhat warm. Remove the man
and hand-hole plates immediately; and, if the blow-off pipe does not enter through the
bottom of the shell, syphon out what water remains, so that the shell and tubes may be
thoroughly dried. The manhole and hand-holes should be left off to allow thorough
circulation of air. If the location of the boiler is very damp, it may be necessary to
build a fire of shavings under it beneath the grates, every few weeks, to keep it in proper
condition.

THE LOCOMOTIVE.

[June.

Incorporated
1866.

Charter Per-
petual.

Issnes Policies of Insnrance aller a Careful Inspection of lie Boilers,

COVEBINO ALL LOSS OB DAMAOB TO

BOILERS, BUILDINGS, AND MACHINERY,

ABISINQ FBOM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Fall information concerning the plan of the Company's operations can be obtained at the

Or at any Agency.

J. M. ALLEN. Prest. W. B. FRANKLIN, Vice-Prest. J. B. PIERCE, Sec'y.

Soard of Directors t

J. M. ALLEN. President.

LUCIUS J. HENDEE. Prest. Mtnsi Fire Ins. Co.

FRANK W. CHENEY, Treas. Cheney Brothers Silk

Manafacturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Amer. Nat. Bank.
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

ManufacturinET Co.
THOMAS O. ENDERS, of.iEtnaLlfeInB. Co.
LBVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Gbn. WM. B. FRANKLIN, Vlce-Prest. Colt's Pat. Fire

Arms Mfg. Co.
GEO. CROMPTON, Crompton Loom Works, Wor-

Hon. THOS. TALBOT, Ex-Qovemor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM 8. SLATER, Cotton Manufacturer, Provi-
dence, R. I.

NELSON HOLLI8TER, of State Bank, Hartford.

CHAS. T. PARRY, of Baldwiu Locomotive Works,
Philadelphia.

Hon. henry C. ROBINSON, Attorney at Law.

GENERAL AGENTS. CHIEF INSPECTORS.

THEO. H. BABCOCK, R. K. McMURRAY,
CORBIN& GOODRICH, WM. G. PIKE,
LAWFORD & McKIM, JOSEPH CRAGG,

W. S. CHAMBERLIN,

J. L. SMITH,

H. D. P. BIQELOW,

C. C. GARDINER,

D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN,
J. H. RANDALL,
A. C. GETCHELL,
J. S. WILSON,

OFFICES.

New York City. OflSce,
Philadelphia. "

Baltimobe. "

Boston, Mass. "

Pbovidence, R. I. "
Chicago, III. "

St. Lonis, Mo. "

Habtfobd. "

Bbidobpobt. "

Clevblaitd. "

ClNOIiniATI. "

285 Broadway.
430 Walnut St.

10 So. Holliday St.

10 Pemberton Sq're.

15 Weybosset St.
132 La Salle St.
404 Market St
218 Main St.
828 Main St.
246 Superior St.

53 West Third St

®fe

0t0motm.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

N"ew Series — Vol. III.

HARTFORD, CONN., JULY, 1883.

No. 7.

Proportions of Riveted Joints.

The cuts in last month's Locomotive show better practice than the average. They
were selected from the proportions of the best and most prominent manufacturers only.
The general practice in the greater number of shops was shown in Figs. 1 and 2, where
the pitch is the same in both single and double-riveted plates. The practice cannot ])e
too strongly condemned, and it is strange that such a system can find followers anywhere
among intelligent boiler makers.

Fig. 1.

Having shown the great diversity of practice in proportioning riveted joints, the
question arises, what are the best proportions for the different thicknesses of plate? We
have shown that the strongest form of joint is seldom realized in practice, and that
double-riveting is invariably badly proportioned. Different reasons are given for this
wide departure from the strongest proportion, the principal one being the impossibility
of making a tight joint with wide pitches. Now we maintain that tight joints can be
made with much wider pitches than are generally used, for we know of several places
where it is done without any trouble whatever. If ordinary skill is used there will be
found no trouble whatever in using 3" pitch for a double-riveted joint in a quarter-inch
plate.

Another strong argument in favor of the widest possible pitch is the fact that more
metal remains to resist the effects of corrosion, which always affects the plate more than
it does the rivet. All things being equal, the life of the boiler will be greater in propor-
tion to the amount of effective material we have to resist deteriorating influences.

After extended observation and mature reflection, we have arranged the following
scale of pitches and rivet diameters for different thicknesses of plates. It will be noticed
that the distance between the two rows of rivets in the double-riveted joints is such that
the distance from the center of any rivet in one row to the center of the next rivet in the
other row is about equal to the pitch in single riveting. This is an important point and
should never be overlooked. By this means we get the advantage of the staunchness due
to a small pitch with the extra metal and greater strength of the wider pitch. We give
cuts of the proportions with calculations of their efficiencies, and invite careful considera-
tion of them, and candid criticism if anyone is disposed to be critical.

THE LOCOMOTIVE.

[TULY,

Referring to Fig. 1 we have : —

Plate i" thick. Rivet hole H" diam. Pitch of rivets, 2".

2._.68T5
Strength of plate at joint = ^ = 66 per cent, of solid plate.

.37122

Strength of rivets at joint = q .)- = 74 per cent, of solid plate.

Fig. 2.

Fig. 2. i" plate, double-riveted. Rivet holes, \y' diam. Pitch of rivets, 3".

3 6875

Strength of plate at joint = — — ^ = 77 per cent, of solid plate.

37122 X 2
Strength of rivets at joint = o^~25 ~ ^^ P^'" ^'^^^- ^^ ^°^'*^ plate.

Fig. 3.
Fig. 3. j\" plate, single riveted. Rivet holes i" diam. Pitch of nvets=2x\

2.0625— .75 ,., ^ ^ TJ , .

Strength of plate at ]oint = .> q^.,- — = 64 per cent, of solid plate.

44179
Strength of rivets at joint = 2062^ x 3125 ~ ^^ ^^^ ^^^^' ^^ ^^^^^ plate.

Fig. 4. y\" plate, double-riveted. Rivet holes f " diam. Pitch of rivets=3i".

3 125— 75
Strength of plate at joint = — ^^ — = 76 per cent, of solid plate.

44179x2
Strength of rivets at joint = 3 i>)5x 31-^5 — ^^ ^^^ ^^^^- °^ ^^^^^ P^^^^"

1883.]

THE LOCOMOTIVE.

Fig. 4.

Fig. 5.

Fig. 5. f" i)l:ite, single-riveted. Rivet holes, [f diam. Pitch of uve*s=2^

Fk;. G.

100

THE LOCOMOTIVE,

[July,

2.125— .8125

Strength of plate at joint = g jog

= 62 per cent, of solid plate.

.51849

Strength of rivets at joint = 3 105 x 375 — ^^ P*^^' ^^^^- °^ ^^^^^ P^^^^"
Fig. 6. t" plate, double-riveted. Rivet holes, ^f" diam. Pitch of rivets=3i".

3.25— .8125

Strength of plate at joint

'3.25

75 per cent, of solid plate.

Strength of rivets at joint = ^^gx 37^5 ~ ^^ P®^ ^®°*- °^ ^° P

Fig.. 7
Fig. 7. y\" plate, single-riveted. Rivet holes, |" diam. Pitch of rivets=2V\'.

2.1875— .875 ,,^ ^ . ,., , ,

Strength of plate at joint = — ^ 1875 ~ ^ P^^ ^^'^ ^

Strength of rivets at joint = 2 1875 X. 4375 ~ ^^ P^'' ^^^*" ^^ ^^^^^ ^^^^^"

Fig. 8.

Fig. 8. iV" plate, double-riveted. Rivet holes, |" diam. Pitch of rivets=3|"

Q Q^s 875

Strength of plate at joint = -^—337^ — = 74 per cent, of solid plate.

ISS*}.

THE LOCOMOTIVE.

101

Strength of rivets at join = 3^~5 J 43~5 — ^^ P^^' ^■^^'^- ^^ ^^'^^^^ plate.

Fig. 9.

Fig. 9. i" plate, single-riveted. Rivet holes, ^ }" diam. Pitch of rivets=2i".

2 25 9375

Strength of plate at joint = ^ o^ = 58 per cent, of solid plate.

69029
Strength of rivets at joint = q".,!^ - = 61 per cent, of solid plate.

Fi(i. 10.

Fig. 10. i" plate, double-riveted. Rivet holes, || ' diani. Pitch of rivet.s— 3^".

?, ,50— 9375
Strength of plate at joint = — -o-^^r = 73 per cent, of solid plate.

09029 X 2
Strength of rivetsat joint = s'sq^T^sq" ^^ P^'' ^^^^- °^ ^^^^^ plate.

The above we believe to be as good and systematic pi'oportions for riveted joints as
liave been published by anyone. We have given the size of the rivet-holes in estimating
the strengtli, in every case. The rivets would of course be -fij" smaller. In practice the
holes generally are not more than ^V' larger than the rivets which are driven in them ; in
that case, the proportionate strength of plate given above would be somewhat increased.

102

THE LOCOMOTIVE,

[JXTLY,

Plates more than i" thick should never be joined with lap-joints. When it is nec-
essary to use them, a butt joint with a double fish plate should always be used. In rec-
ommending the above proportions, we assume that the workmanship is always fair. In
these days there is no excuse for poor and slouchy workmanship under any circum-
stances.

TABLE OF THE FOREGOING PROPOTITIOXS.

Thickness of plate, -
Diameter of rivet,
Diameter of rivet-hole,
Pitch — single-riveting,
Pitch — double-riveting,
Strength of single-riveted joint,
Strength of double-riveted joint.

-u

«i

¥i

2tV

.66

.64

.62

.60

.77

.76

.75

.74

1 5

Tff

.58

.73

Inspectors' Reports.

May, 1882.

The usual monthly summary of the work done by the Inspectors of the company
during the month of May last, is given below. From it we learn that 2,612 visits of
inspection were made, during which 5,419 boilers were examined. The number of com-
plete internal inspections foots up 1,874, and 487 others were subjected to hydrostatic
pressure. The number of boilers considered worn out and unfit for further use was 39.

The total number of defects found was 2,859, of which number 637 were considered
to be of so serious a character, as to impair the safety of the boilers in which they were
located. The following detailed statement of defects shows their precise nature.

Nature of defects. Whole number. Dangerous.

Cases of deposition of sediment, - - - -

Cases of incrustation and scale, - - . .

Cases of internal grooving, - - - - -

Cases of internal corrosion, -----

Cases of external corrosion, - - - - - <

Broken and loose braces and stays, - - - -

Settings defective, - - - - . -

Furnaces out of shape, . . . . -

Fractured plates, ------

Burned plates, .-.---

Blistered plates, ------

Cases of defective riveting, -----

Defective heads, - . -

Leaky tubes, ------

Leaky seams, ------

Water-gauges defective, - . . . -

Blow-out defective, ------

Cases of deficiency of water, ....

Safety-valves overloaded, - - - . -

Safety-valves defective in construction,

Pressure gauges defective, .... -

Boilers without pressure gauges, ....

One dangerous defect unclassified,

Total. - - 2,859 - - 637

285

428

129

174

- 108

225

269

402

141

174

1882.]

THE LO'COMOTIVfi,

103

HARTFORD, JULY, 1883.

The following article was originally prepared for The Boston Journal of Commerce,
and appeared in its issue of July 1st :

Some months ago I prepared an illustrated article for fhe.Journal of Commerce on
machine riveting. My object was not to condemn machine riveting, but to call the atten-
tion of boiler makers who used riveting machines to the fact that, imless such machines
were under the management of skillful men, very poor work might be turned out. It
was shown that the failure to so adjust the parts — that the axes of the moving cup-
shaped die, fixed die, and rivet hole, were coincident — would result in forming the head
on one side of the body of the rivet. The illustrations, made from rivets in this office,
could not fail to convince any careful observer of the necessity of great care in the use
of the riveting machine. When business is driving and the boiler maker is overwhelmed
with orders, he finds the riveting machine of great service, because the work can be so
much more rapidly done by it, and it is just here that the liability to carelessness comes
in. "With due care in adjustment there is no doubt but that a very eft'ective, I will say,
superior joint, can be made by a riveting machine.

I introduce here illustrations of three (3) rivets which have come into my possession
since the last article was written :

Fig. 1.

Fig. 8.

They only furnish additional evidence that the proper adjustment of the machine
and the work to be done is sometimes overlooked.

The question has been raised as to whether the great force with which the rivet is
driven will not tend to so enlarge or expand the body of the rivet as to endanger that
portion of the plate extending from the rivet holes to the edge ; that is, start a fracture
from the holes outward. I have watched for this defect, but have failed to detect it. I
am told, however, that others have satisfied themselves that it is sometimes true.

If it is so, may it not result from using a rivet of too great length for the thickness
of plate ?

We can readily see that when the rivet is driven, any excess of metal must find a
place for itself somewhere. My own observations have been that, under such circum-
stances, it flows out underneath the face of the die, forming a "^«," as shown by the
following illustrations:

104

THE LOCOMOTIVE.

[JUI>Y,

Fig. 4.

Fic. 5.

It has been said that a " tin '' could not be formed on a rivet head made by a ma-
chine. But suppose we have a rivet containing more than metal sufficient to fill the rivet
hole and the cup-shaped dies ; it must flow somewhere, and it will go in the place of
least resistance, which will be out underneath the face of the die. This point of relief
is to my mind sutRcient to prevent any damaging strain being brought upon the plates
from the enlarging of tlie body of the riret. But it is well to bear in mind that the
rivets should be adapted in length to the thickness of plate, and to the capacity of the
cup-shaped die, or dies.

In hand riveting, an excess of metal is disposed of by distributing it over a larger
area, or by giving the apex of the head greater altitude above the jilate. In machine
riveting, the shape and size of the head is determined by the die. J. M. Allen.

Prof Antonio Favaro of the Royal University of Padova, Italy, has published a very
interesting and valuable work on Acoustics, as applied to the construction of churches,
public halls, &c. It has been our privilege to have more or less correspondence with
Prof. Favaro on this subject, and we are gratified to have the results of his investiga-
tions. The laws of Acoustics are so little understood, or so little attention is given to
the subject by builders of churches and public halls, that there are many in this country
as well as foreigTi countries, where everything is sacrificed to architectural eft'ect. The
Professor points out these defects, and lays down some rules by which these bad efiects
may be remedied or avoided. The work is printed in Italian; we are not aware that it
has been translated into English.

In John W. Nystrom's Treatise on Steam Engineering, page 103, he says, under the
heading DovUe-Eiveted Laj) Joints : " Double-riveted joints, if properly proportioned, in-
crease the strength of the boiler about forty per cent., on account of the rivets l>eing
spaced farther apart, leaving more section of plate between them to resist the strain. The
rivets are arranged in two rows, ziz-zag over one another, as shown in the illustration.
For the greatest strength the distance between the rivets in the direction of the joint
should be double the distance between the center lines of the two rows, and the rivets
will then form a right angle, or 90° with one another."

The illustration which he gives is in accord with our own views, and will, with due
proportion of size of rivet to thickness of plate, give the strongest double-riveted joint.
Our own method of arriving at tlie size of rivet is based upon the thickness of plate, and
the pitch is determined from the thickness of plate and size of rivet. The distance of
the center lines of the two rows of rivets we make equal to half the} pitch. This gives
the same result as is shown in Mr. Nystrom's illustration, viz., the rivets form a right
anffle, or 90° with one another.

1882.] THE LOCOMOTIVE. 105

We have noticed of late articles on Riveted Joints in several mechanical journals
which were stolen bodily from an article prepared in this office, and which ajipeared in
the LocoiiOTrvE of Sejitember, ISSl. One English paper has copied it, crediting it to
an Exchange. "We do not object to having articles co2)ied from the Locomotive, but ex-
pect that every honorable journalist will give us due credit. To cojjy rerlatim et litera-
tim, with no credit, is no better than stealing, and we are ready to believe that no
honorable journalist would knowingly be so discourteous. It is proper to say that the
attention of those who have done this has been called to the matter, and their explana-
tions in the main have been satisfactory. Some of our articles have been prepared at no
little expense and labor, and if they are used by others, due credit should be given.

We are indebted to the Pennsylvania Iron and Steel Co. for specimens of liveted
joints. There are hand-driven, button set. and hydraulic machine-driven rivets. The
work in each case is first-class. The relative merits of the different methods can be
readily seen. The Pennsylvania Iron & Steel Company say that they give the prefer-
ence to machine riveting in their works.

We also are favored with a specimen joint made with Johnson's Riveting ]\Iachine.
Mr. Johnson of Xew Orleans, the inventor, explained to us personally the peculiarities of
his machine. The work is so adjusted that the rivets stand perpendicular when driven.
He has a piston within a piston, one to bring the plates together and the other to drive
the rivet. He claims that with his machine a rivet cannot be driven with the head
offset. We have had numerous communications bearing on the question of machine
riveting, since we called attention to the bad work that is sometimes done through care-
lessness, with such machines.

We are indebted to Howard Lockwood, Esq., Publisher, for a copy of Grimshaw's
work, called the Miller,, Millwright,, and Mill-furnisher. It is a book of between 500 and
600 pages, and pretty thoroughly covers the ground indicated by its title. It will no
doubt have a large sale among men engaged in the milling business. *

The ifecAa/iic«Z ^/j^meer of New York- is growing in favor among mechanics. It
senior editor, Mr. E. P. Watson, was formerly editor of the Scientijic American, and he
knows how to make a valuable paper. Read their articles entitled the "Professor in
the Machine Shop.'"

At the meeting of the Master Car-Builders' Association, held in Philadelphia on
June 13th, Mr. 'SI. W. Forney, of the Rnlroad Gazette,, stated that from 1,200 to 1,500
employees are killed annually on our railroads, and from 5,000 to 10,000 injured.

A BRASS steam-whistle, thought to be the largest ever made, has just been finished
by the Eaton, Cole & Burnham Co., 58 John St., New York. It is of cast brass, 4 ft. 9 in.
in length, the bell having a diameter of twenty in. Its weight is 400 lb., and its value
$500. The supply pipe is 4 in. in diameter. It goes to a large steam saw mill in
Canida, where it is to be employed, with a system of signals, to give orders to the lum-
bermen at a distance, and to summon the widely scattered employees in case of fire.
— Scientific American.

106

THE LOCOMOTIVE.

[July,

Specific Gravity Table,

The folio-wing table of Specific Gravities, etc., has been condensed from Trautwine's
Engineers" Pocket Book. The third column, which will be found useful in many cases,
has been added by us. The table will be found of very great use in ascertaining the
weight of anything which it is not convenient to weigh, but can be measured. Such,
are boilers, large masses of metal, beams, floors, and walls of buildings, tanks and barrels
of water, etc. The cubic contents being obtained by measurement, the weight may
easily be computed.

Table of the Weight jlsd Specific Gravity of Different Substances.

Name of Substances.

Gravity. °°® ^"""^ "• Cu. in.

Air, atmospheric at 60° and under the pressure of one atmos-
phere, or 14.7 lbs. per sq. inch, weighs -g\-g part as much as
water at 60°, -.----.-.

Alcohol, pure, -

Alcohol of commerce,

Ash, American white, dry,* (see foot note, p. 108,)

Ash, American white, 1,000 ft. board measure weighs 3,167 lbs..

Bismuth, cast. Also native, -------

Brass, (Copper and Zinc) cast, 7.8 to 8.4. Average,

Brass, rolled-sheet,

Bronze, gun metal, copper 8 parts, tin 1, 8.4 to 8.6,
Brick, best pressed, 1,000= 5,750 pounds (8^"x4"x3"),
" common hard, 1,000=4,800 " " " -

" soft inferior, 1,000=3,850 " " " - -

Charcoal, of pines and oaks,

Coal, Anthracite, of Pennsylvania, 1.3 to 1.7, average, -
broken, of any market size, loose,

" " " " " shaken, -

a heaped bushel, loose, weighs 77 to 83 lbs.,
' 2,240 lbs., loose, averages from 40 to 43 cu. ft.,
2,000 " " " " 36 to 39 " "

Bituminous, 1.2 to 1.5, average, ----#-
broken, of any market size, loose,
u u u u u shaken, -

a heaped bushel, loose. 70 to 78 pounds,
2,240 lbs. occupies 43 to 48 cubic feet,
2,000 " " 39 to 43 "

Cherry, perfectly dry,* (see foot note, p. 108,) . - -

" 1,000 ft. board measure weighs 3,500 pounds, -
Chestnut, perfectly dry,* (see foot note, p. 108,) . -

" 1,000 ft. board measure weighs 3,416 pounds,
Cement — hydraulic, Rosendale, ground, loose, average, -

" U. S. struck bushel = 70 lbs.,

Louisville, " " " " =62 "

English, Portland. U. S. struck bushel=

100 to 128, -----

Cement— hydraulic,English, Portland, a barrel=400 to 430 lbs.,

Copper, cast, 8.6 to 8.8,

rolled, 8.8 to 9.0, ..-----

Cork,

Earth, common loam, perfectly dry, loose, - - - -
" " " •' shaken, - - - -

" " >' " " moderately rammed,

" " " as a soft flowing mud, - - - -

Elm, perfectly diy,* average, (see foot note, p. 108,)

" 1,000 ft. board measure weighs 2,916 lbs.,

u
a

a
u

((

.00123

.793

.834

.61

9.74
8.1
8.4
8.5

1.5

1.35

.672
.66

8.7
8.9
.25

.56

.0765

49.43

52.1

607

504

524

529

150

125

100

15 t6 30

93.5

52 to 56

56 to 60

.0286

.0301

.023

.3513
.2916
.3033
.3061
.0868
.0723
.0579

.0541

.0486

47 to 52

51 to 56

.0243

.0237

49.6

81 to 103

542

.3136

555

.3212

15.6

73 to 80

83 to 93

90 to 100

04 to 113

.0202

1882.]

THE LOCOMOTIVE.

107

Name of Sttestaxces.

Glass, 25 to 3.45, average,

Glass, common window, average,

Granite, 2.56 to 2.88, average, . . . . .

Gneiss, common 2.62 to 2.76, average, - - - -

Gravel, about the same as sand, which see.

Gold, cast, pure, or 24 carat, ------

" native, pure, --------

'■'• pure hammered, 19.4 to 19.6, r - - -
Hemlock, perfectly dry,* (see foot note, p. 108,) -

" 1,000 ft. board measure weighs 2,083 pounds.

Hickorj', perfectly dry,* (^see foot note, p. 108.)

'' 1,000 It. board measure weighs 4.415 pounds.

Iron, cast,

" " usually assumed at, - - - - -

When 1 cubic ft. =450 lbs.; 1 cubic in. =.2604 lb. and one
pound=3.84 cubic in., 2,000 pounds= 7,680 cubic in.

Iron, wrought, - -

" " large rolled bars,

' " " " usually assumed at,

' sheet,

When 1 cubic ft. =480 lbs., 1 cubic in. =.2778 lb., one
pound=8.6 cubic in., 2,000 pounds=7,200 cubic in.

Ice,

Lead, average, - .

Lime, quick, average, - - . . - .

" " either in small irregular lumps or ground, loose,

50 to 58,

Lime, quick, ground, loose, 62 to 70 lbs. per struck bushel, -
" " " well shaken, 80 " " "

" " " thoroughly shaken, 93| lbs. per struck

bushel, --

Mahogany, dry Spanish,* average, (see foot note, p. 108,)

" " Honduras, "

Maple,* dry, average, (see foot note, p. 108,) - - . -

1.000 ft. board measure=4,083 pounds.
Masonry, of granite or limestone, well dressed throughout, -
" '• well scabbled mortar rubble, \ mortar, -
^' _ " " " dry rubble,

" brickwork, medium quality, - - - .

Mercury at 60°, .-.----.-

Mortar, hardened, 1.4 to 1.9, average,

Oak, live, perfectly drv,* " (see foot note, p. 108,) -

" white, " « .1

" red, " " "

Pine,white. perfectly drj-,* .35 to .45, average, (see ft n'te, p. 108,)

1,000 ft. board measure=2,083 pounds.
Pine, yellow Northern,* .48 to .62, average, (see ft note, p. 108,)

1,000 ft. board measure=2,858 pounds.
Pine, Southern,* .64 to .80, average, (see foot note, p. 108,) -

1,000 ft. board measure=3,750 pounds.
Powder, slightly shaken, - - - . -

Platinum, 21 to 22,

Salt, coarse, per struck bushel, 56 pounds, - - - -

" fine, for table use,

Sand, dry and loose, 112 to 133 lbs. per struck bushel, -

Sand, at the average of 98 lbs. per cubic ft., one cubic
inch=.0567 lb., 2,000 lbs.=20.4 cubic feet, one struck bushel
= 122^ pounds.
Sand, perfectly wet, -

Average
Specific
Gravity.

Weight of
one Cubic ft.

186

Weight
of one
Cu. in.

2.98

.1076

2.52

157

.0908

2.72

170

2.69

168

19.258

1204

.6967

19.82

1206

19.5

1217

.7042

.0145

.85

.0306

6.9 to 7.4

430 to 461

7.21

450

.2604

7.6 to 7.9

474 to 493

7.6

474

7.69

480

.2778

485

.2807

.92

57.4

.0332

11.41

711

.4114

1.5

53
53
64

.85

.56

.79

165

154
138
125

.0283

13.58

846

.4896

1.65

103

.95

59.3

.0343

.77

48
32 to 45

.0278

.40

.0145

.55

84.3

.0198

.72

.026

1.00

62.3

21.5

1342
45
49

.7766

2.65

90 to 106
118 to 129

i08

THE LOCOMOTIVE

[July,

Name of Si-bstances.

Average
Specifl^c
Gravity.

Weight of
cue Cubic ft.

Weight
of one

Cu. in.

■Sqovt, fresh fallen, - -

5 to 12

" moistened and compacted by rain, - - . -

15 to 50

Slate, 2.7 to 2.9, averaue, ...----

2.8

175

Silver, - - . . -

10.5

655

.379

Steel, 7.7 to 7.9, average. -------

7.85

490

.2835

•Spruce, perfectly dry,=^ average,

.0145

1,000 ft. boaid measure =2,083 pounds.

Zinc, 6.8 to 7.2, average, - - - - • -

7.0

437.5

.2532

Tin, cast, 7.2 to 7.5, average, -------

7.35

459

.2656

Water at 32° Fahr., - - -

7.35

62.417

U U QOO i. ----- - - -

1.00

62.355

.03607

" 212° " . -

59.7

Water at 60° Fahr.. a cubic inch = .03607 lb. = . 57712 oz.,

and a pound=27.724 cubic in., which is equal approxi-

matelv to a cube 3" on each edge — more exactly, the cube

* Green timbers usually weigh from one-fifth to nearly one-half more than dry ; and ordinary building tim-
Ijers when tolerably seasoned, about one-sixth more than perfectly dry.

Things Worth Remembering about Water.

The following was condensed from D. K. Clark's Manual of Rules, edition 1877.

Four notalle temperatures, vh. :

32° = the freezing point under one atmosphere of pressure.
39°r = the point of maximum density.
62° = the British standard temperature.
212° = the boiling point under one atmosphere of pressure.

Weight of one cuMc inch of water.

= .03612 pounds = .5779 ounce = 252.84 grains.
= .036125 pounds = .578 ounce = 252.875 grains.
= .03608 pounds = .5773 ounce = 252.595 grains.
= .03451 pounds = .5522 ounce = 241.5875 grains.

Weight of one cubic foot of loater.

— 62.418 pounds.
At 39°r = 62.425 pounds = greatest weight of one cubic foot.
At 62° = 62.355 pounds = Standard temperature.
At 212° = 59.640 pounds.

Volume of one pound of pure water.

At 32° = .016021 cubic feet = 27.684 cubic inches.
At 39 1' = .016019 cubic feet = 27.680 cubic inches.
At 62° = .016037 cubic feet = 27.712 cubic inches.
At 212° = .016770 cubic feet = 28.978 cubic inches.

The volume of one ounce of pure water at 62° = 1.732 cubic inches.

The weight of water contained in a cylindrical vessel one foot in diameter and one
foot high at 62° = 48.973 pounds.

The weight of water contained in a cylindrical vessel one inch in diameter and one
inch high at 62° = .02833 pound, or .4533 ounce.

The weight of one gallon of water at 62° = 10 pounds.

At 32°
At 89°1'
At 62°
At 212°

At 32°

1882.] THE LOCOMOTIVE. 109

The volume of one gallon of water at 63° = 277.123 cubic inches,'^or .160372 cubic
foot.

One cubic foot of water contains Q^ gallons nearly.

The volume of water at 62° in cubic inches, multiplied by .00036, gives the capacity
in gallons.

The capacity of one gallon is equal to one square foot ^1.924 inches dtey =[2''
inches nearly, or to one circular foot 2.-4o inches deep = 2^" nearly.

One ton (2,240 pounds) of water at 62° contains 224 gallons.

One ton (2,000 pounds) of water at 62° contains 200 gallons.

One hundred pounds of water at 62° contains 10 gallons.

Volume of given weights of icater at 52°8' = Q'iA 'pounds per cubic foot.

1 ton = 35.9 cubic feet.

1 hundred weight = 1.795 cubic feet.

1 quarter = .449 cubic foot.

1 pound = .016 cubic foot = 27.692 cubic inches.

1 ounce = 1.731 cubic inches.

One cubic yard, or twenty-seven cubic feet of water weighs about fifteen hundred
weight, or three-fourths of a ton.

A pipe three feet long holds about as many pounds as the square of its diameter in
inches (exactly two per cent. more).

Pressure of tcater,

A pressure oi one p)0und per square inchh exerted by a column of water 27.71 inches^
or 2.3093 feet high at the temperature of 62°.

A pressure of one atmosphere, or 14.7 pounds per square inch, is exerted by a
column of water 33.947 feet high at 62°.

A column of water at 62°, one foot high, presses on the base with a force of .433;
pound, or 6.928 ounces per square inch.

A column of water one inch high presses on the base with a force of .5773 ounce per
square inch., or 5.196 pounds per square foot.

Water is only slightly compressible. Experiments show that for every atmosphere,.
or every 14.7 pounds pressure per square inch applied to it, it is reduced 47^ millionths-
of its bulk.

The U. S. standard gallon contains 231 cubic inches instead of the 277.274 of the
British standard.

The XJ. S. standard ton contains 2,000 pounds instead of 2,240, as in the British ton,
and the quarter and hundred weight are in the same proportion.

The pound used in this article is the Standard Avoirdupois poimd and the grain is^
the Troy grain of which the Avoirdupois pound contains exactly 7000 and the Avoirdu-
pois ounce 437|. The Troy grain is much used at the present time in weighing small
quantities by Avoirdupois weight.

One of the most remarkable features brought out at the meeting of the Master Car
Builders' Association at Philadelphia on the 13th ult., and at the last two or three meet-
ings, has been the introduction of railroad freight car brakes which are practically
automatic in their application, and which can be used by the engine when the cars to
"which they are applied are scattered through a long train and unconnected with each
other, save through the ordinary links and pins of the draw-bars. Probably no problem
in the mechanical world ever presented greater difficulties than this, and yet from the last
reports of the Master Car Builders' Committee on Train Brakes for Freight Cars, it
would seem that a very high degree of efficiency has already been obtained. — Mechanics^

llO THE LOCOMOTIVE. [July,

Iron and Steel Production in 1881.

The report of the Secretary of the American Iron and Steel Association for 1881,
just completed, gives the following summary of the year's work : Production of pig iron
in net tons, 4,641,564, including 21,086 tons of spiegeleisen ; production of all rolled
iron, including nails and excluding rails, 2,155,346 tons; Bessemer steel rails, net tons,
1,330,302 ; open hearth steel rails, net tons, 25,217 ; iron and other rails, net tons, 488,-
581; production of iron and steel street rails included in above, 21,554; crucible steel
ingots, net tons, 89,762 ; open hearth steel ingots, net tons, 146,946 ; Bessemer steel
ingots, net tons, 1,539,157 ; blister and patent steel, net tons, 3,047. Production of all
kinds of steel, net tons, 1,778,912. Production of blooms from ore and pig iron, net
tons, 84,606. Imports of iron and steel, $61,555,078. Imports of iron ore, gross tons,
782,887. Exports of iron and steel, $15,782,282. Production of Lake Superior iron ore,
gross tons, 2,336,335 ; production of iron ore in Jersey, gross tons, 737,052. Total pro-
duction of iron ore in census year 1880, net tons, 7,974,705.

Production anthracite coal in census year 1880, net tons, 28,646,995. Production ot
bituminous coal in census year 1880, net tons, 42,420,581. Production of anthracite coal
in 1881, gross tons, 28,500,016. Miles of railway completed in 1881 : 9,650 miles of
railway track in the United States, December 31, 1881, including double track and
siding estimated, 130,000. Iron ships built in the United States in the fiscal year
ending June 30, 1881, 42. — Scientific American.

Specifications for Boiier and Fire Box Steel, issued by the Pennsyl-
vania Railroad Company, February 1, 1881.

First. A careful examination will be made of every sheet, and none will be.received
that show mechanical defects.

Secrnid. A test strip from each sheet, taken lengthwise of the sheet, and without
annealing, should have a tensile strength of 55,000 pounds per square inch, and an
elongation of thirty per cent, in section originally two inches long.

Third. Sheets will not be accepted if the test shows a tensile strength of less than
50,000 or greater than 65,000 pounds per square inch, nor if the elongation falls below
twenty-five per cent.

Fourth. Should any sheets develop defects in working they will be rejected.

Fifth. Manufacturers must send one test strip for each sheet (this strip must ac-
company the sheet in every case), both sheet and strip being properly stamped with the
marks designated by this company, and also lettered with white lead, to facilitate

marking.

The Treasury Department on June 9 issued a circular addressed to supervising and
local inspectors of steam vessels, boiler makers and otliers, suspending the operation of
the formulas for the construction of boiler flues less than 16 inches in diameter, which
were promulgated by the department circular, No. 30, issued March 14th of this year.
The object of this suspension is to permit the objections of boiler makers to the formulas
as originally laid down, to be presented to the Board of Supervising Inspectors for
consideration at its next meeting. From representations made by the leading l^oiler
makers in the West, it appears that the formulas in question are, in many respects,
impracticable. These views, we understand, are endorsed by the Supervising Inspector-
General, which leads to this action upon the part of the Government. — Mechanics.

1882.] THE LOCOMOTIVE. H^

Notes and Queries.

An Engineer, Duluth says : — Please give me thpough the Locomotive a simple rule
or determining the correct diameter and •' lift " of check valves, of single acting plunger
pumps such as are generally attached to direct acting steam engines ?

Ans. "We have never seen any rule in any of the various treatises on the steam
engine, for determining the lift of check-valves under varying circumstances. For fast
running pumps, such as locomotive feed-pumps, the lift must of course be less than for
slow running pumps. Forney in his Catechism of the Locomotive^ says the lift of locomo-
tive feed-checks varies from fY' to ^". In our own opinion h' is too much. An old
master mechanic on one of our Eastern roads says, that the practice some years ago was
to give checks ^", -f^" or f" lift according to size of valve. The tendency of locomotive
builders of the present day, however, when pumps are used, is to increase the diameter
of the valve and give it less lift.

Our own experience with feed pumps for stationary engines, convinces us that ^" is
about as much lift as a check-valve should have under any cii'cumstances. We use the
following empirical rule for determining the lift of checks under ordinary circumstances,
and it has always given good satisfaction.

Divide 2^ by the square root of the number of strokes per minute made by the
pump ; the quotient will be the proper lift in fractions of an inch. Suppose we have a
pump making 120 strokes per minnte; then 'y/120 = 11 nearly. 2^ -^11= .23" lift.

Having determined the lift, the diameter of the valve should be such that the area
of clear opening in valve, should be about equal to area of pipe in which the valve is
placed, and it may be calculated by the following rule :

Multiply the internal area of the pipe in which the valve is to be placed by 1.4,
divide the product by the lift of the valve, from the quotient subtract the product of
half the lift multiplied by 3.1416; the remainder is the circumference of the opening
through valve, which divided by 3.1416 will give the required diameter.

For example suppose we wish to find the size of valve required for a one inch feed
pipe. !

Assume for simplicity that the speed of the engine is slow, then the lift of the valve
may be \ of an inch.

The internal area of a one inch pipe is given by the makers as .86 of a square inch.

Then we have' ^- ' =4.82; 4.82 minus (3.1416 X^) =4.42; and 4.42 divided

by 3.1416 = ly*jj = required diameter of valve.

The area of opening for a miter valve of any given diameter and lift is found as
follows : Multiply half the lift of the value by 3.1416, and add the product to the circum-
ference of the opening through valve; multiply this sum by the lift; and divide this
last i^roduct by 1.4; the quotient will give the area of the clear opening in square inches.

According to the Sacramento Record, the largest locomotive in the world was
recently completed at the Central Pacific shops in that city. The cylinders are 19" x
30"; four jtairs of drivers; weight on drivers. 53 tons. The boiler shell is of Otis steel,
5 feet in diameter and 17 feet long, with 166 tubes 2^" diameter; dome. 26" diameter by
40" high. The total length of boiler is 29 feet 2^ inches, and the weight 14 tons. The
distribution of steam is assisted by supplementary valves working on the back of the^nain
slide. The capacity of tank is 3,000 gallons of water, and of tender o tons of coal. — Am.
Machinist.

112

THE LOCOMOTIVE.

[July.

Incorporated
1866.

Charter Per-
petual.

Issnes Policies of Insnrance alter a Careful Inspection of tte Boilers,

COVERING ALL LOSS OR DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

ARISING FROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full information concerning the plan of the Company's operations can be obtained at the

Or at any Agency.

J. M. ALLEN, Prest. W. B. FEANKLIN, Vice-Prest. J. B. PIBECB, Sec'y.

Board of Directors :

J. M. ALLEN, President.

LUCIUS J. HENDEE, Prest. .(Etna Fire Ids. Co.

FRANK W. CHENEY, Treae. Cheney Brothers Silk

Manufecturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Amer. Nat. Bank.
RICHARD W. H. JARVIS, Prest. Colt's Fire Anns

Manufacturing Co.
THOMAS O. ENDERS, of .<Etna Life Ins. Co.
LEVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Hon. HENRT C. ROBINSON, Attorney at Law

Gen. WM. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire
Arms Mfg. Co.

GEO. CROMPTON, Crompton Loom Works, Wor-
cestcr.

Hon. THOS. TALBOT, Ex-Governor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manufiicturer, Provi-
dence, R. I.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. PARRY, of Baldwin Locomotive Works,
Philadelphia.

GENERAL AGENTS. CHIEF INSPECTORS.

OFFICES.

THEO. H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKIM,
W. S. CHAMBERLIN,
J. L. SMITH,
H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FREEMAN.
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

R. K. McMURRAY,
WM. G. PIKE,
JOSEPH CRAGG,
WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN,
J. H. RANDALL,
A. C. GETCHELL,
J. S. WILSON,

New York City.

Philadelphia.

Baltimore.

Boston, Mass.

Providence, R. I.

Chicago, III.

St. Louis, Mo.

Hartford.

Bridgeport.

Cleveland.

Cincinnati.

Office, 285 Broadway.
" 430 Walnut St.
" 10 So. Holliday St.
" 10 Pemberton Sq'r*^

15 Weybosset St.
" 132 La Salle St.
" 404 Market St.
" 218 Main St.
" 328 Main St.
" 246 Superior St.
" 53 West Third St.

Witt JTaraniatte.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY,

New Series— Vol. III. HARTFORD, CONK. AUGUST, 1882.

No. 8.

Boiler Construction and Setting-.

In the March number of The Locomotive we gave an illustrated article showing the
construction and setting of a horizontal tubular boiler, 20 feet long, 66 inches in diameter,
containing 54 tubes, each 4 inches in diameter. A number of boilers of this type have
been built and set under the supervision of the Hartfokd Steam Boiler Inspection
AND Insurance Co., and they have in every case worked fully up to and beyond our
expectations. They are of unusual dimensions, and to insure the best results the setting
must be carefully done. In most cases chimneys have been planned with special reference
and adaptation to them, so that we have not recommended them except where an
entirely new boiler-house and chimney were tobe erected. A more common size of boiler
is 16 feet 8 inches long outside and GO inches in diameter, containing 66 tubes, each
3 inches in diameter. Tiie front of the boiler is what is known as the projecting front,
as shown in the following Fig. 1. The tube-heads are 15 feet apart; tubes 15 feet

A- STEAM MOZZLE

Fl(!. 1.

long. They are set in vertical and horizontal rows, with a broader central vertical space.
The tubes are arranged to secure the best circulation of water. There are 20 braces in
all— 10 on each head. Tliese braces are secured to ])iece8 of T-iron placed radially on
each head, as shown in Fig. 2. We iiavc found tliis mctliod of securing braces advanta-
geous for two reasons. Tlie pnll of the brace is straigiit from the web of the T-iron, a
jaw Ix'ing made on the end of tlie l)race, which is pinned and keyed to the web; and
second, the pieces of T-iron riveted to the iiead give it stiffness. Tiie braces should be
made of iron at least one inch in diameter, with no rneld.

Every boiler should be supplied with two nozzles, one ff)r steam and one for safety-

114

THE LOCOMOTIVE.

[August,

valve. The jiractlce of putting up a nest of boilers with only one safety-valve is danger-
ous and pernicious. Every boiler should liave its own independent safety-valve. It will
be noticed iu Fig. 1 tliat there is a door at rear end of setting 3 feet by 2 feet. This is
important to facilitate cleaning the bottom of boiler, and for removing ashes that may

accumulate in rear of bridge wall. We
would call attention also to the man-hole
frame. It should be put on the inside of
boiler shell. If well done, a more effective
re-inforcing of the strength of man -hole is
secured, as well as a tighter joint. We
have discussed this point in The Locomo-
TivE in previous numbers, and we have
■0 also tested it in practice. In preparing the
foundations for boiler settings great care
should be taken to see that they are iirm.
Many boiler foundations are simply brick-
work laid on the ground. When the
boiler has been used a short time the foun-
dations settle and the walls crack and
tumble down. Do the work well, even if
it costs a little more to begin with ; it will
be economy in the end. The walls should
be heavy, with air spaces iu the center to
-p , Q prevent fractures from expansion and con-

traction. Fig. 3 shows the plan of boiler
and setting. The feed should be introduced through its own independent pipe, with
suitable check and stop-valves. It is not good practice to blow and feed through the

Fig. 3.
same pipe. There are many details in the designing construction, and setting of boilers
wliich must not be neglected if safety and economy are to be attained.

Tubes of greater diameter than 3 inches may be used with good results; all depends
upon their proper arrangement. The Haktfokd Steam Boii.ru Inspection and Insur-
ance Co. furnishes plans and specifications for both boilers and settings for its patrons,
and will supervise the settings if desired. It also prepares ])lans for boiler-houses and
chimneys. Hundreds of boilers are now in use which have been built and set from its
plans and specifications.

1882.] THE LOCOMOTIVE. 115

Inspectors' Reports.

June, 1882.

The one hundred aud eighty-uiuth monthly summary of the reports of the Com-
pany's Inspectors is given below, and will well repay a careful perusal. From it we
learn that 2,142 visits of inspection were made aud 4.535 boilers were examined. The
number of thorough annual internal inspections reaches a total of 1,803, and 364 boilers
were proved by hydrostatic pressure.

The whole number of defects found which were considered sufficiently serious to be
reported, was 2,898, of which number 661 were considered to be of so grave a nature as
to impair the safety of the boilers in which they were found. The number of boilers
condemned, was 44. The usual analysis of defects is given below.

Nature of defects.
Cases of deposition of sediment, _ . .

Cases of incrustation and scale, . _ .

Cases of internal grooving, - - - -

Cases of internal corrosion, - - - -

Cases of external corrosion, - - - -

Broken and loose braces and stays, - - -

Settings defective, -----
Furnaces out of sha])e, - . - .

Fractured plates, -----
Burned plates, . - . - -

Blistered plates, -----

Cases of defective riveting, - - - -

Defective heads, . - . - .

Leakage around tubes, . . - -

Leakage at seams, -----
Tyatcr-gauges defective, . . - -

Blow-out defective, -----
Cases of deficiency of water,

Safety-valves overloaded, . . - -

Safety-valves defective in construction.
Pressure-gauges defective, - - - -

Boilers without ))ressiu-e gauges,

Total, - - 2,898 - - 661

The matter of defectire settings, as well also as the proper design fur a boiler setting
originally, is one that is every day becoming of greater importance. As comi^etition in
different lu'anches of manufactin-ing industry becomes eacli succeeding year closer, every
avenue of waste must be closed as far as it is possible to do so, and nuiiuifacturers find
themselves obliged to economize in all things. This being the case, it will readily be
seen that users of steam power are interested to the greatest possible extent in cvery-
tliing that tends to the eccmomy of fuel; for the item of coal in any manufacturing
establishment running by steam power must necessarily be a very important one.

It is very difficult to imagine conditions more unfavorable to the stability and
duraT)ility of Vjrickwork generally, than those which obtain in the case of the ordinary
externally tired horizontal tubular boiler. One part of the setting is exposed to a very
intense heat, while other parts are always exposed to draughts of cold air, and in many
cases which have come under the writer's observation, every shower or snow storm
caused a complete deluge of the brickwork with cold water. Under such circumstances

Whole number.

Dangerous.

311

442

109

160

105

174

311

297

214

164

154

HQ THE LOCOMOTIVE. [August.

masonry must give way, walls will ci-ack open, and settle down, and bulge out, and
general disarrangement of steam and water connections must inevitably result. Of
course some of this action is unavoidable, from mere changes of temperature, but the
extent of it depends to a great extent u[ion the manner in which the work is done
originall}'.

As much, perhaps, depends upon the design, as ujion the (juality of tlie workman-
ship as far as the durability of the setting and economy of the boiler is concerned. The
side walls and back end wall of a boiler setting should always be closed in to the shell a
few inclies below the normal watei line. This is absolutely essential to the safety of the
boiler. Under no conditions sliould the top of the shell be exposed to the direct action
of the heated products of combustion. Seri(ms trouble will always arise when this is
allowed. The sheets are l)urncd, fractures occur, the seams are loosened, and a boiler in
nine cases out of ten will be reduced to an absolutely dangerous condition in a com-
paratively short time.

One of the commonest defects to which boilers set with a flush front setting are
liable, is the burning and breaking off of the shell on the lower side just forward of the
front tul)e-sheet. This is caused by the tire-brick arch over the furnace door becoming
loose and tumbling down, tluis exposing the dry portion of the shell to the direct action
of the intense heat of the furnace fire. When this is the case a very short time only
suthces to heat the shell at this point red iiot, and the expansion is in itself sufficient to
fracture it. While this defect is not necessarily dangerous, it is apt to so strain the joint
between the shell and the flange on the tube-sheet, that persistent leakage, resulting in
corrosion at this point, is the consequence.

Another important point to which we Avould call the attention of boiler owners is
the method of sup])orting the shells of boilers. They sliould always have strong, sub-
stantial brackets, riveted, not bolted, on the side of the shell, and should have a strong
pier of Wrv brick built up to take the weight of the boiler. These piers should be about
2 feet long and should be perpendicidar on their face. A cast iron plate extending
nearly theii- whole length should be laid on top of them to distribute the weight of the
boiler over the whole pier as much as possible. Of course the brackets at back end of
boiler should rest on rolls so that tlie resistance to contraction and expansion shall be as
little as possible.

The thickness of the side and end walls of boiler settings should not be too much
scrimped. AVhere a battery of boilers are set together, the distance between the shells
should l)e two feet at least. The walls between any two adjacent boilers need not have
an air s[)aee, hut they should not be tied together; they should belaid up independently
of each other, Itut close togetlier. The advantages of this plan will be apparent when it
is wished to lay any one boiler in the battery off. Then the liability of cracking the
wall is much reduced if they are laid u|) separately.

The outside walls, both of the side and back ends of the setting, should always be
laid up double, with a good air space between. The thickness of the air space sliould
be not less than two inches, and that of the outer wall not less than 8"; that of the inner
wall a foot at least. For a GO-inch boiler it should be about 14 inches at top of grate
and should batter outwards to a line 3 inches from the shell of the boiler at the height,
where the wall is closed in. The plans of boiler and setting in this issue show the proper
method of setting boilers.

If attention be given to the above points, and the mason does his work properly
the repairs on the setting will be reduced to a nuninunn.

1882.] THE LOCOMOTIVE. 117

*tttmi!titt

HAETFORD, AUGUST, 1882.

In our examinations of boilers we not infrequently find a strange disregard of all
rules and regulations for the safe management of boilers. We say strange, for it hardly
seems possible that intelligent men would encourage or allow a disregard of rules that
are known to be safe. "We can account for it only on the ground that the desire to meet
every demand for his product blinds the manufacturer to the danger of overworking his
boilers. We have of late found safety-valves overweighted 15 and 20 pounds. When
the engineer was asked why he had changed the weight on the safety-valve, his reply was
that his employer wanted more steam and had ordered him to increase the weight
on the valve. These men would feel very much aggrieved to be accused of dishonesty.
But suppose the boiler had exploded in the meantime and killcMl several persons. Would
these men have stood up and said, "We increased the load on the safety-valve and are
responsible for this disaster." Probably they would have kept very (juiet and thrown the
responsibilit}- on the insurance company or on the inspector. Men sometimes have two
kinds of morality — one for church and the family and another for business. If men will
take the responsibility of their own acts and not endeavor to throw it on to others when
disaster comes there will be a higher tone of morality in business.

Another difficulty is the desire to use old boilers at excessive pressures. "We must
have more steam,'' is the cry. Why not get new boilers constructed for the pressure you
want? Then you could do your work easily and safely. Tliis penny -wise policy of
working boilers beyond their safe limit is a strange phenomenon. And how men reputed
to be wise and ])rudent can be so short-sighted is the mystery.

They sometimes get very much disturbed because we will not assent to their de-
mands. Oftentimes they pay no attention to the condition of their boilers, and know
nothing of the rules for casting the safe working pressure of boilers, but they want so
much steam, and they are going to have it. We give them the limit that we are willing
to be responsible for, and say if you want more you must take the responsibility and we
will withdraw our certificate; and we have withdrawn it in a. number of instances lately.
We hope those who have taken the responsibility will go through unharmed, but if acci-
dent should occur their reflections will not be cheerful.

Wc say to all steam users. Don't ]iresume to overwork old boilers, nor work any
boilers l^eyond a safe ])ressure. If yoin* business demands more steam get new boilers,
and you will do your work easier and liave a clearer conscience.

We have just received the Report of j\Ir. ^Miciiael Longridge, Chief Engineer of the
Engine, Boiler, and EmployerH' Liahility Insurnncc Company, Manchester, England, for the
year 1882. It contains very full and complete accoimts of Boiler Explosions in England
during the past year; a very inttircsting report of the trial of a ])air of compound en-
gines; many specimens of indicator diagrams taken by tlie company's engineers, and
which illustrate queer practices in the use of steam, and a good amount of very sensible
information regarding the construction and management of engines and boilers
generally.

1^8

THE LOCOMOTIVE

[Atjgtjbt,

Wrought Iron Welded Tubes for Gas, Steam, or Water.

Tabi,e of SiWNDARD DIMENSIONS. {Miwrin, Taskev & Co., Limited.)

\\" and below, butt welded
1^" and above, lap welded

Proved to ;}00 Ib.s. \\qv si], inch by hydraulic pressure.

•3

'S c
a <o

•38

-a
'5/

a
o

1
o

"3
a
u

.2
a

►—1

B
<u

Sq'areln.

Length of pipe per
sq. ft. of inside
surface.

Length of pipe per
sq. ft. of outside
surface.

§4^
« _:

Weight per foot
of length.

Inch's

Inches.

Inch's.

Inches.

Square In.

Feet.

Pounds.

.27

.405

.068

.848

1.272

.0572

.129

14.15

9.44

2,500.

.243

.364

.54

.088

1.144

1.696

.1041

.229

10.50

7.075

1,385.

.422

.494

.675

.091

1.552

2.121

.1916

.358

7.67

5.657

751.5

.561

.623

.84

.109

1.957

2.652

.3048

.554

6.13

4.502

472.4

.845

3
4

.824

1.05

.113

2.589

3.299

.5333

.866

4.635

3.637

270.

1.126

1.048

1.315

.134

3.292

4.134

.8627

1.357

3.679

2.903

166.9

1.670

1.38

1.66

.140

4.335

5.215

1.496

2.164

2.768

2.301

96.25

2.258

1.611

1.9

.145

5.061

5.969

2.038

2.835

2.371

2.01

70.65

2.694

2.067

2.375

.154

6.494

7.461

3.355

4.430

1.848

1.611

42.36

3.667

2.468

2.875

.204

7.754

9.032

4.783

6.491

1.547

1.328

30.11

5.773

3.067

3.5

.217

9.630

10.996

7.388

9.621

1.245

1.091

19.49

7.547

3.548

4.0

.220

11.146

12.566

9.887

12.566

1.077

.955

14.56

9.055

4.026

4.5

.237

12.648

14.137

12.730

15.904

.949

.849

11.31

10.728

4.508

.247

14.153

15.708

15.939

19.635

.848

.765

9.03

12.492

5.045

5.563

.259

15.849

17.475

19.990

24.299

.757

.629

7.20

14.564

6.065

6.625

.28 19.054

20.813

28.889

34.471

.63

.577

4.98

18.767

7.023

7.625

.301

22.063

23.954

38.737

45.663

.544

.505

3.72

23.410

7.982

8.625

.322

25.076

27.096

50.039

58.426

.478

.444

2.88

28.348

9.001

9.688

.344

28.277

30.483

63.633

73.715

.425

.394

2.26

34.077

10.019

10.75

.366

31.475

33.772

78.838

90.762

.381

.355

1.80

40.641

11.224

12.

.388

35.261

37.699

98.942

113.097

.340

.318

1.455

47.727

12.180

13.

.41

38.264

40.840

116.535

132.732

.313

.293

1.235 54.655

13.136

14.

.432

41.268

43.982

134.582

153.938

, .290

.273

1.069 61.940

14.092

15.

.454

44.271

47.124

155.968

176.715

.271

.254

.923 70.008

15.048

16.

.476

47.274

50.265

1 '5 7. 867

201.062

.254

.238

.809 78.269

16.004

17.

.498

50.278

53.407

201.102

226.980

.238

.225

.715 87.120

16.960

18.

.520

53.281

56.548

225.907

254.469

.225

.212

.638 96.379

17.916

19.

.542

56.284

59.690

252.096

283.529

.213

.201

.571 106.067

18.872

20.

.564

59.288

62.832

279.720

314.160

.202

.191

.515 116.214

19.828.

21.

.586 62.291

65.973

308.771

346.361

.192

.183

.466126.760

^ inch pipe,

NUMBER OF THREAD PER INCH OP SCREW.

27 threads per inch.

-to u i( i:

14 " '< '<

lU " "

ecommended instead of screwed ends.

I inch and | incli pipe,

1 U "3 " •'

2 4 • •

1 " IJ- incli, 1^ inch, and 2 ini
All sizes larger than 2 inch,

For sizes above 10 inch diameter flanges are r

\\ i.ii)c.

TAPER OF THREADS PER INCH OF SCREW.

\ inch to 8 inch pipe, inclusive, ^t^ incli per incli in lengtli of screw.
9 inch to 20 " " "

1882.]

THE LOCOMOTIVE.

119

Lap Welded American Charcoal Iron Boiler Tubes.

Standard Dimensions. {Table of Morris, Tasker cfc Co., Limited.)

Diam.l-

Circum-

Clrcum-

of tube
foot of
Surface.t

f tube per
t of Out-
rface.l

■3

S
u
<s

1 =

1*.

Is
w

. — 0

C C
t, 4)

as 0

a a

■4-*

"3
a

u
a>

■4.3

1*^

5 1/ 30

2 *j'

Inches.

Inches

Inches.

Square Ins.
.575

Square Ins.
.785

Feet.

Pounds.

.856

.072

2.689

3.142

4.460

3.819

.708

1.106

.072

3.474

3.927

.960

1.227

3.455

3.056

1.334

.083

4.191

4.712

1.396

1.767

2.863

2.547

1.25

1.560

.095

4.901

5.498

1.911

2.405

2.448

2.183

1.665

1.804

.098

5.667

6.283

2.556

3.142

2.118

1.909

1.981

2.054

.098

6.484

7.069

3.314

3.976

1.850

1.698

2.238

2.283

.109

7.172

7.854

4.094

4.909

1.673

1.528

2.755

2.533

.109

7.957

8.639

5.039

5.940

1.508

1.390

3.045

2.783

.109

8.743

9.425

6.083

7.069

1.373

1.273

3.333

3.012

.119

9.462

10.210

7.125

8.296

1.268

1.175

3.958

3.262

.119

10.248

10.995

8.357

9.621

1.171

1.091

4.272

3.512

.119

11.033

11.781

9.687

11.045

1.088

1.018

4.590

3.741

.130

11.753

12.566

10.992

12.566

1.023

.9.^5

5.32

4.241

.130

13.323

14.137

14.126

15.904

.901

.849

6.01

4.720

.140

14.818

15.708

17.497

19.635

.809

.764

7.226

5.699

.151

17.904

18.849

25.509

28.274

.670

.637

9.346

6.657

.172

20.914

21.991

34.805

38.484

.574

.545

12.435

7.636

.182

23.989

25.132

45.795

50.265

.500

.478

15.109

8.615

.193

27.055

28.274

58.291

63.617

.444

.424

18.002

9.573

.214

30.074

31.416

71.975

78. .40

.399

.382

22.19

10.560

.22

33.175

34.557

87.479

95.033

.361

.347

25.489

11.542

.229

36.26

37.699

103.749

113.097

.330

.318

28.516

12.524

.238

39.345

40.840

123.187

132.732

.305

.293

32.208

13.504

.248

42.414

43.982

143.189

153.938

.282

.272

36.271

14.482

.259

45.496

47.124

104.718

176.715

.263

.254

40.012

15.458

.271

48.562

50.265

187.067

201.062

.247

.238

•45.199

16.432

.284

51.602

53.407

212.227

226.980

.232

.224

49.902

17.416

.292

54.714 •

56.548

238.224

254.469

.219

.212

54.816

18.400

57.805

59.690

265.903

283.529

.207

.200

59.479

19.360

.32

60.821

62.832

294.373

314.159

.197

.190

66.765

20.320

.34

63.837

65.973

324.311

346.361

• .188

.181

73.404

•The thicknesp of Tubes can be varied to order.

+ It is imposHible to make Tubes ni exact internal diameter.

Jin estimating the effective steam-heating or boiler surface of Tubes, the surface in contact with air or
gases of combustion (whether internal or external to the tubes) is to be taken.

For heating lifjiiids by steam, superheating steam, or transferring heat from one liquid or gas to another,
the mean surface of the Tubes is to be taken.

Magnesia Bricks and Moulders' Sand. — Magnesia ol)tainod by decomposing
chloride of magnesium, as free from silica as possible, is formed into briquettes and heated
to a white heat, then ground and mixed with a little water or tar, and made into bricks,
and again Ijurned to a white heat. As magnesium bricks shrink greatly in burning, Mr.
S. G. Thomas places in the kiln an occasional layer of lime l)ricks as a binding layer, and
is thus able to build them up much higher without fear of their falling while being biu-nt.
The briquettes above mentioned, ground, are stated to be an excellent substitute for
moulders' sand, as they are quite infusible, and do not stick to steel castings. — Boston
Journal of Commerce.

120

THE LOCOMOTIVE

[August,

Properties of Saturated Steam.

Pressure per
Steam-gauge.

S3 .

S (U S

Degrees.

♦" a _ •^

Heat Units.

§g

So
*j a

C 3
0/ o

3" 1

a o

|l 1

's o a

0=3
B a

o<«
t„ - o

= m o ?
O

Lbs.p'rSq.In

Heat Units.

Pounds.

Cubic Keet.

Cubic Feet.

212.0

180.9

965.7

1,146.6

.03797

26.336

1.642

227.2

196.3

955.0

1,151.2

.05

20.

1.246

239.4

208.7

946.3 i

1,154.9

.0619

16.16

1,008

249.8

219.2

938.9

1,158.1

.0736

13.59

847

258.8

228.4

932.5

1,160.9

.0852

11.74

732

2G6.8

236.6

926.8

1,163.3

.0967

10.34

645

274.0

243.9

921.6

1,165.5

.1081

9.27

577

280.6

250.7

916.9

1,167.5

.1195

8.37

521

286.7

256.9

912.5

1,169.4

.1308

7.65

477

292.4

262.7

908.4

1,171.1

.142

7.04

439

297.7

268.2

904.6 1

1,172.7

.1531

6.53

407

302.6

273.2

901.1

1,174.2

.1643

6.09

380

307.3

278.0

897.7

1,175.7

.1753

5.7QL

356

311.8

282.6

894.4

1,177.0

.1863

5.37

335

•$16.0

286.9

891.4

1,178.3

.1973

5.07

316

320.0

291.1

888.4

1,179.5

.2082

4.80

299

323.9

295.1

885.6

1,180.7

.2192

4.56

282

327.6

298.9

883.0

1,181.9

.23

4.35

271

331.2

302.0

880.4

1,182.9

.2409

4.15

259

334.6

306.1

877.9

1,184.0

.2517

3.97

248

100

337.9

309.5

875.5

1,185.0

.2625

3.81

238

105

341.1

312.8

873.15

1,186.0

.2732

3.66

228

110

344.2

316.0

870.9

1,186.9

.2839

i 3.52

220

115

347.2

319.1

868.7

1,187.8

.2946

3.39

212

120

350.1

322.1

866.6

1,188.7

.3053

3.28

204

125

352.9

325.0

864.5

1,189.6

.3160

' 3.17

197

130

355.6

327.8

862.5

1,190.4

.3266

3.06

191

135 •

358.3

330.6

S60.6

1,191.2

.3^72

2.97

185

140

3G0.9

333.3

858.6

1,192.0

.3478

2.88

179

145

363.4

335.9

856.75

1,192.7

;3584

2.79

174

150

30.-). 9

338.5

855.0

1,193.5

.3b89

2.71

169

155

368.3

341.0

1 853.25

1,194.3

.3794

2.64

164

IGO

370.7

' 343.5

851.5

1,11)5.0

.3899

2.56

160

165

373.0

345.9

849.8

1,195.7

.4004

2.50

156

170

375.2

348.2

S48.2

1,196.4

.4109

2.43

152

175

377.4

350.5

846.6

1,197.1

.4213

2.37

148

180

379.0

352.8

845.0

1.197.7

.4318

2.32

144

185

381.7

355.0

843.4

' 1,198.4

.4422

2.26

141

190

383.8

i 357.2

841.8

1,199.0

.4526

.2.21

138

195

385.8

359.2

840.4

1,199.6

.4630

' 2.16

135

200

387.8

363.3

836.9

1,200.2

.4734

2.11

132

Rule for Ascertaining- the Cubic Contents of Masses, Brolcen, Rough,

and of Irreg-ular Form.

It not unfrequently occiirs in the experience of those who have to do with small
castings of brnss, silver, iron, and even lartjer cnstiniis, too-etlier with carved work of
.Stone or marble, or irregular and broken lumps of any material, that some convenient
rule for ascertaining the cubic contents of the same, in mass or singly, w^ould be very
desirable. Some thirty years ago the writer settled a dispute over the cubic contents of

1882.] THE LOCOMOTIVE. 121

a very irregular broken piece of stoue to the entire satisfaction of botli the disputants,
neither of whom was right. I give the j^vocess for the benefit of our readers. A tub
was secured of sufficient depth to allow the irregular mass to be entirely submerged
when placed on the bottom of the tub, and the tub filled with water to the brim. By
small copper wires, which had been previously attached to the irregular piece of stone,
it was carefully lifted out so as not to spill any of the water. This done, the cubic
contents of the water in the tub was ascertained, also the cubic contents of the tub.
The difference between these two results was the cubic contents of the irregular piece of
broken stone. To make this plainer if jiossible, I will su2>pose that we have a lump of
broken coal as large as one's two fists, more or less, the cubic contents of which we wish
to ascertain. First secure a tin pail with straight sides. (1 say straight, because the
contents of the pail can be more easily cast), ascertain the cubic contents of this by the
following rule: Multiply the square of the diameter in inches by the decimal .7854, and
this result by the depth of the pail in inches. The last result will be the cubic contents
of the pail in inches. Now place the lump of coal in the pail, having fastened a small
copper wire to it, and fill the pail to the brim. Remove the coal carefully by means of
the copper wire. Then ascertain the number of cubic inches in the water remaining in
the pail by multiplying the square of the diameter of the pail in inches, by the decimal
.7854 (as above), and this result by the dej>th of water in inches. Subtract this last result
from the cubic contents of tlie pail, and you have the cubic contents of the lump of coal.
By this process the cubic contents of bent and twisted pieces of metal can be easily
ascertained, also pieces which are turned into fantastic shapes. A square, water-tight
box may be used instead of a circular vessel or ])ail. The cubic contents of such a
vessel is easily ascertained by multiplying the internal length, breadth, and depth
together. To ascertain the cubic inches in the water when the box is only partially full,
multiply the length, breadth, and depth of the body of water together.
Some verv vexing problems can be easily solved by this simple rule.

J. M. A.

Superheated Water.

We rcpul)lis]» the following article from our issue of January, 1880, believing it will
be of interest at the present time. It is an extract from an article published some years
ago in the American Artisan. It was writt(;n by Mr. A. Guthrie, formerly U. S. Super-
vising Inspector General, and the ten experiments seem to include about all the methods
of de-aijrating water that are likely to occiu- in the use of steam boilers.

"In the American Artimn of the 20th inst. (page 45), I was pleased to find some
communications from corres])ondents of your valuable paper in reference to boiler
explosions being caused by de-aerated and 'superheated' water. This theory — that
water deprived of its natural pro])()rtion of air can ever be heated above a J)oiling point
due to the pressure, and in consequence becoming explosive — has in my humble ojjinion,
gone far enough to meet a positive contradiction. A theory advanced by M. Donny, an
obscure chemist, as long back perhaps as 1770, In'ing of itself simply ridiculous, has
found advocates up to the present day. That this theory has been copied into many
works on chemistry and science, and assented to by learned men during one liundred
years, excites my wonder; but that it has not found its refutation in its own absin-dity
seems to me still mon; singular. I am glad to see that at least one of your correspond-
ents, Mr. Geo. B. Brayton, has the boldness to contradict it.

" I have made many experiments to satisfy myself of the truthfulness of this theory,
and have endeavored to conduct them with j'crfect fairness and impartiality, and with
all the care that my feel>I(! abilities would permit. I am entirely satisfied that there is
not a shadow of truth in the Doiuiy theory, that water deprived of air ])oils at a higher

122 THE LOCOMOTIVE. [August,

temperature or at any different temperature than water not so deprived ; nor is there any
foundation whatever for the statement that such water has the slightest explosive ten-
dency more than any other water. I mean exactly, that it will boil at 212" Fahrenheit
when other water does, and that it will come to a point of ebullition without a particle
of tendency to ex])losion. no more than any other water, just this, exactly.

"I concede that Prof. Tyndall has in his lectures in a manner given credit to this
theory, but the moment after and before concluding he declaims his belief in it so
plainly that he need not be misunderstood.

"I admit that Brand and Taylor in their work on ' Chemistry ' (which, by the bye,
is a work of exceeding value), with many other distinguished writers, have adopted this
theory as the true one ; but I am led to think it has been adopted without reflection and
without investigation. It may a])pear to be great presumption in me to contradict tliis
theory with the positiveness I do; but did I not suppose I had given it the fullest
investigation, with just as good means to give it a fair trial as any one, I should not
venture to contradict.

" In the first place, I assume as true that all natural water has a small percentage (say
two and a half) of atmospheric air mixed with it; in this I believe we all agree. Now,
then, I assume that this air may be expelled in the process of congelation ; by boiling for
a given time; by distillation out of contact of air; by placing it in vacuo; and by being
absorbed in tish or water-breathing animals in their kind of res^iiration. I suppose there
is little difference of opinion upon these points.

"(1.) In my experiments, I first procure a sample of water from the boiler of an
ordinary condensing engine; here, of course, in addition to being subjected to long-
continued l)oiling, it had passed through the vacuum.

"(2.) I procured a sample from the ordinary high-pressure non-condensing engine
boiler, which before entering the boiler had passed the heater at 210°.

"(3.) I procured some clean snow and dissolved it under oil, so that there was no
contact with the air.

"(4.) I froze some water in a long upright tube, using only the low^er end of the ice
when removed from the tube, and dissolved under oil.

"(5.) I placed a bottle of water under a jjowerful vacuum jjump worked by steam,
for two hours ; agitating the water from time to time to displace any air that might
possibly be confined in it, then closed it by a stop-cock, so that no air could possibly
return.

"(6.) I boiled water in an open boiler for several hours, and filled a Ijottlc half-full,
closed and sealed it up, so that when it became cool it would in effect be under a vacuum ;
agitating it as often as it seemed necessary.

"(7.) Another bottle was filled with the same, and sealed.

"(8.) I next took some clean, solid ice, dissolved it under oil, and brought it to a
boil, which was continued for an hour or more, after which it was tightly corked.

"(9.) I procured a bottle of carefully distilled water, after long boiling and having
been perfectly excluded from air during the distillation.

"(10.) I obtained a large number of small fisli, placed them in pure, clean water in

an open-headed cask in a moderately cold night, so that very soon it became frozen over,
consequently excluding the air, the fish breathing up the air in the water, so that (if I
am correct in this tlieory) a water freed from air would be the result; but in aome of
these different processes, if not in all, I was likely to free the water from air, if it could
ever possibly occur in the ordinary course of operating a steam boiler.

" Having procured a good supply of glass boilers adapted to my purpose, and so made
that the slightest changes could be noted, and using as delicate thermometers as I could
obtain, I took these samples one after another, and brought them to the boiling i^oint ;
and every one wuth no variation whatever, boiled effectually and positively at 212®
Fahrenheit or under; nor was there the slightest appearance of explosion to be
observed."

1882.] THE LOCOMOTIVE. 123

Misapplying the Steam Jacket.

The object of applying steam jackets to steam engines is to keep the steam doing
work from artificial condensation by the external temperature as long as jjossible. In
other words, to keep its vital heat at the temperature at which it entered the cylinder,
less that lost necessarily by doing useful work. There have been differences of opinion
upon the utility of jacketing steam cylinders, and able engineers have not hesitated to
state their disbelief in them. In such cases there may have been causes operating simi-
lar to those here related :

A writer in the recent number of the Engineering relates that he had occasion to
believe that the steam jacket applied to compound marine engines was seldom used, or if
used at all, improperly. His observations are divided into five classes. He found thir-
teen vessels where the jackets were used as follows: The engineers said:

"I work the jacket with the outlet to the condenser or hot well full open, and tem-
per the live steam supply to the jacket by the valve. I prefer this plan because there is
then no trouble with the water."

On three steamers the engineers said: "I use the jacket on starting only, to warm
up the cylinder, and keep the steam from condensing during stopping and starting.
When under way I shut off the jacket, because there is no use in it when the cylinders
are well lagged."

On two steamers the engineers said: "I work with the steam inlet full open, but
keep the drain cock shut, and blow the water out once on a watch."

On three steamers the engineers said: "I dinna trouble meself much aboot the
jecket, for I canna see what difference it can make."

On two steamers the engineers said : " I keep the live steam on all the while, and
regulate the drain so as to keep the water out without wasting steam."

By this testimony, which in some respects is ludicrous, it will be seen that it is easy
to make out that a jacket is or is not economical, according as it is used. It also shows
the risk attending taking testimony upon the merits of economical apparatus without
absolute certainty as to the manner in wliich the same was treated. — Mechaniail Engineer.

Weight of a Million Dollars.

Mr. E. B. Elliott, the Government Actuary, has computed the weight of a million
dollars in gold and silver coin as follows:

The standard gold dollar of the United States contains of gold of nine-tenths fine-
ness, 25.8 grains, and the standard silver dollar contains of silver of nine-tenths of fine-
ness, 412.0 grains. One million standard gold dollars, consequently, weigh 25,800,000
grains, or 53,750 ounces troy, or 4,479 1-6 pounds troy, of 5,760 grains each, or 3,685.71
pounds avoirdupois of 7,000 grains each, or 1 843-1,000 " short " tons of 2,000 pounds
avoirdupois each, or 1 645-1,000 " long " tons of 2,240 pounds avoirdupois eacli. One mil-
lion standard silver dollars weigh 412,500,000 grains or 85!),375 ounces troy, or 71,-
614.58 pounds troy, or 58,928.57 pounds avoirdupois, or 29 464-1,000 " sliort " tons of
2,000 pounds avoirdupois each, or 26 307-1,000 " long" tons of 2,240 pounds avoirdupois
each. In round numbers the following table represents the weight of a million dollars
in the coin named:

Description of coin. Tons.

.Standard gold coin If

Standard silver coin, 26}

Subsidiary silver coin 25

Minor coin, 5 cent nickel, 100

— Scientific American.

124 THE LOCOMOTIVE. [August,

Thing's Worth Remembering' About Air.

[Condensed from D. K. Clark's Manual of Rules, Tables, and Data.]

The mean pressure of the atmosphere at the level of the sea is equal to :

14.7 pounds per square inch, or
2,116.4 " " " foot.

This pressure is equivalent to a column of air at 32° F. of uniform density, (equal to
that at the level of the sea,) 27,801 feet high, or

A column of mercury at 32° F. =29.922 inches high,
u n 62oF. = 30. " "^

" water 32o F. = 33.913 feet " (Freezing point.)

" " 390 F. =33.909 " " ^Maximum density.)

" " 62° F. =33.947 " " (Standard temperature.)

A pressure of one pound per square inch is equal to :

A column of air at 32° F., of uniform density as above, 1,891 feet high, or,
" mercury at 32° F. = 2.035 inches high.

" " 62° F. =2.04 " "

" water 32° F. =27.684 " "

" " 390 F. =27.68

" " 62° F. =27.72 " "

A pressure of one pound per square foot is equal to : ^

A column of air at 32° F., of uniform density as above, 13.13 feet high.
" mercury at 32° F. = .0141 inch high.

<' " 62° F.=. 01417 " "

" water 32° F. = . 19225 '' "

" " 39° F.=. 19222 " "

" " 62°F.=.1925

The density or weight of one cubic foot of pure air, under a pressure of one atmos-
phere or 14.7 pounds per square inch is:

At 32° F. =.080728 pound, or 1.29 ounce, or 565.1 grains.
" 62° F.=. 076097 " 1.217 " 532.7 "

Tlie weight of air compared Avith that of water at three notable temperatures, and at
52.3° F., under one atmosphere, is as follows: _

Weight of water at 32° F. = 773.2 times the weight €f air at 32° F.
" " 39.1° F.=773.27 " '' " 32° F.

" " 62° F.=772.4 " " " 32° F.

" " 62° F.=819.4 " " " 62° F.

a ci 52.3° F. =820. " " " 62° F.

The volume of one pound of air, at 32° F., and under one atmosphere of pressure,
is 12.387 cubic feet. The volume at 62» F. is 13.141 cwlnv feet.

The specific heat of water being 1 : —
" " " air under constant ])rcssurc is .2377.

" " " " " " volume is .1688.

Or in other words, if we enclose air in a cylinder provided with a piston moving
freely, so that when the air is heated it can expand, and the pressure remain the same,
then the (]uantity of heat necessary to raise the temperature of one pound of water one
degree from 39.1° to 40.1° will raise the temperature of 4.207 pounds of air one degree.
And, if we enclose air in the cylinder and secure our piston so that the air cannot expand
when it is heated, then the quantity of heat whicli will raise the temperature of one
pound of water one degree, from 39°. 1 to 40.°1 will raise the temperature of 5.924
poimds of air one degree.

The following rules will be found to be practically useful.

Rui.,E 1. When the volume of any given weight of air at any given temperature
is known, to find its volume at any other temperature, the pressure remaining the same.

1882] THE LOCOMOTIVE. 125

Multiply the given rolume by the temjjerature at which the Doltime is reqtiired + 461,
and divide the product by the given temperature + 461 ; the quotient is tJie required volume.
Example. The volume of one pound of air at 33*^ F., under one atmosphere of
pressure is 12.387 cubic feet; required its volume at 212° F., at the same pressure.

12.387 x(212+461)=8336.45 and 8336.45-^(82 + 461) = 16.91 uearly^thevohime of oue
pound of air at 212°, and under one atmosjihere of pressure.

Rule 2. When the pressure of any given weight of air at any given temperature
and volume is known, to lind its pressure for any other temperature and volume.

Multiply the given pressure by the given volume, and this pjroduct again by the tempera-
ture f&r which the p/ressure is requi)-ed + 4:Ql ; divide this last product by the product of the
new volume multiplied by the given temperature +4iM.

Example. The pressure of one pound of air at a temperature of 32° F., at a vol-
ume of 12.387 cubic feet is 14.7 pounds per square inch; wliat is its pressure at a tempera-
ture of 212° and volume of 20 cubic feet?

14.7 X 12. 387 x(212+462) = 122o45.8297 and 122545.8297-f-20x (32+461) ^12.428 the
required pressure.

The Locomotive Industry.

In a recent number of the liailway Age there is published an article on the locomo-
tives in the United States, in which some figures relating to the locomotive industry
and its jnospects for the future are given that are likely to be of interest to our readers :

The number of locomotives on the 104,325 miles of railway in the United States at
the commencement of the present year is stated by Poor's Manual as 20,116, an increase
of 2,167 over the number reported one year previous. In our issue of December 8, 1881,
we estimated the numl)er of engines manufactured during the year at private works and
railway shops as about 3,000, of which probably 1,000 would take the place of machines
worn out and retired. This would give a net increase of about 2,000, which nearly cor-
responds with the actual figures given in the ^Manual, whose statistics, however, it must
be remembered, do not come within the exact Ijound*; of the calendar year, as they are
made up from the railway reports. Avhich terminate at various periods. It is interesting
to note that, taking the Manual's totals of railway mileage and number of engines for
the last two years, they give nearly the same average number of miles per engine, that
for 1880 being 5.21 miles, and that for 1881 being 5.18 miles showing a slight and not
unnatural falling oil in the average, as the roads opened into new country do not at first
require as large equi])ment as those upon which business is developed. Had the average
of 1880 continued, the increase for last year would have been only 9,'d locomotives more
than that actually reported. The number of engines added this year is likely to be
somewhat less than that built in 1881, as orders were, in many cases, curtailed when the
temporary depression of last winter and s])ring came, and the lost time cannot be
recovered, even if the demand greatly increases, as it seems certain to do. The 15 loco-
motive works in the United States, however, appear to be fairly busy, and some we know
have orders ahead sufficient to run them through the year. Most of them have increased
their productive capacity, and one or two new works are being constructed. The build-
ings are being erected for one of these near Chicago, but the works are not likely to be
finished in time to offer much competition this year.

Prices of locomotives have fallen somewhat. The fact is, they were higher last year
than necessary to afford a good profit, but as the manufacturers had all that they wanted
to do, and the railways must have the engines at any price, it is not strange that as high as
$13,500 was asked and paid for an eight-wheel passenger engine. The locomotive
builders made money enough last year to enable them to stand a little lower prices,
although they are in no danger of suffering this year. The railways will have a heavy

126 THE LOCOMOTIVE. [August,

business, the country is prosperous, and the manufacturers are as much entitled to share
in tlie general prosperity as are tlu; farmers, many of whom will grow rich with a single
year's harvest. — Mec/ianics.

Regenerative Gas Burners.

At a recent meeting of the Glasgow Philosophical Society, Scotland, Mr. William
Foulis read a paper on the Siemens regenerative gas burner. He said that the general
principle of this burner was the he.iling of tlic gas and air supplies before they reached
the point of combustion. This idea was suggested by Professor Faraday as early as
1843. The luminosity of a flame is due to the incandescence of the small particles of
carbon, which, by the ordinary method of burning gas, are dissociated from the hydro-
gen gas in the earlier stages of the process of combustion. The important points to
consider in connection with the question of the economical consumption of gas are (I)
that the separation of the particles of carbon should be as complete as possible, and (2)
to have the greatest available number of these particles disseminated throughout the
flame. The limit of the separation of the solid particles was the point at which the
flame began to smoke, and the stage of the combustion process at which the greatest
degree of luminosity took place was just the point before the emission of smoke began.
Another consideration was that the higher the quality of the gas, the sooner did the
point arrive at which it began to smoke. In order to insure a perfect separation of the
carbon particles the gas should be burned at a very low pressure; and moreover, the
temperature of the flame should be as high as possible, in order that the carbon particles
may be very highly heated, and also that a greater number of them may be maintained
in the state of incandescence. In the Siemens burner the gas is heated to a temperature
of from 600° to 700° F., and thus the flame temperature greatly increased. — Mechanics.

The End of the World.

"I had a horrible dream the other night," said George Freeman, of New York, to a
party of friends the other evening. "Tell us about it," said one. "Well, I dreamed
that while sitting in my ottice and looking out on Broad street I saw an unusual excite-
ment on the sidewalk. I leaned out and asked 'What's the matter?' 'The world is
coming to an end,' said one excited man as he ran for his life. Just then in walked
William H. Vanderbilt, and says I, ' Billy, what can you do to save us? ' ' Oh, that's all
right; you stay by me and you'll pull through all right. You see I've got the Celestial
branch of the New York Central put through, and when the liual bust comes we'll get
aboard the special train and be all right.' ' Just hold the train a minute, will you, till I
send up town for my wife and children.' ' Certainly,' says William, and I immediately
called my son, who looked very queer as he walked in, and no wonder, for his head was
covered with a fungus growth of chessmen, knights, queens, kings, and pawns scattered
all over his head in a wonderful manner. 'How did you come by those?' 'Don't
know,' said he; 'they came on all of a sudden last night.' 'Well, never mind; go up
town and get your mother and family and bring them down quick as possible.' The
dutiful boy left. In a few minutes I had a telephone message from the house from my
son, saying that ' mother is down at Macy's. What shall I do? ' ' Great heavens,' I cried,
'that woman is always at Macy's.' 'Go after her,' I yelled, and began packing up
my valuable papers. Meantime William H. was pacing up and down the office with
an anxious look upward to the sky. 'Ah,' he murmured,' here she comes.' 'What
comes?' said I. 'The Celestial branch train,' he replied, complacently. I looked up
and saw about a hundred miles in the zenith a long train of Pullman sleepers plowing

1882.] THE LOCOMOTIVE. >[27

down through space with comet-like velocity. The train then stopped and several bal-
loons immediately descended corner of Broad and Wall streets. There was a great
scramble for seats, but William H. had engaged a squad of the 'finest' to beat the
crowd back. My wife having arrived with her bundles from Macy's, we got on the car
and shot up to the train. William II. did the square thing by giving us all a through
ticket, and we were soon bowling through space at tlie rate of 42,005 miles a second.
At the end of the first second after starting we heard a fizz like a wet fire-cracker, and
looking down we saw that the world had really come to an end, like an ignited torpedo.
We had traveled but a few winks more and had come in sight of the pearly gates, when
a terrific roar was heard and the whole train evaporated. The boiler had exploded. I
instinctively grasped my wife's back hair to save her life, and we both fell down through
space like a rocket-stick. The next thing I heard was my wife's voice saying: 'Good
land! George, what are you doing there on the floor? Come back to bed and don't act
like a fool.' I went ' back,' and, I forgot how I acted, but I remember crawling imder the
sheet all covered Avith goose pimples and a horrible taste in my mouth. — The Revieic.''''

A Super-Sensitive Thermometer.

Since the days when Mr. Edison brought out his microtasimeter, which proved so
sensitive to heat, until now, Ave have had no instnnnent devised for measuring extremelv
delicate changes of temperature. Such an apparatus has, however, been recently devised
by M. Michelson, and brought, at least, in its experimental form, before the French
Physical Society. It is based on the principle of bi-metallic thermometers, but ebonite
or hard caoutchouc is -chosen instead of one metal. Hard rubber is ten times more dilata-
ble than platinum under heat, and a spring comjiosed of j)latinum on one side, and ebon-
ite on the other, will curve under tlie least increase of temperature. At the extremity of
the spring is fixed a small glass stem forming an elbowed lever which abuts against a
light mirror suspended by a silk fil)rc. When the spring curves or straightens, the mirror
is deflected, and a ray of light from a lamp reflected from its surface to a scale that moves up
or down the divisions of the scale. By giving to the spring and lever a relatively great
length, this instrument can be made very sensitive, and the inventor hopes to be able to
measure the thousandth of a degree centigrade. — Engineering.

English and A.merican Machinery in Russia. — Reporting njjon the trade of
Odessa in the year 1881, Consul Stanley directs special attention to the strong demand
which exists in the south of Russia for agricultural machinery. Few villages, he states,
are without at least one agricultural steam engine, and as there is only one manufactory of
these engines in Ru.ssia — viz. , that of Maltzof — they are largely imported. Notwithstand-
ing the great extra cost of English engines, due to freight, insurance, and duty — an extra
cost, which on an engin6 sold in England for £240 may, Consul Stanley estimates be
placed at £100 — the Russians are willing to pay the higher price, because of the greater
durability and better working of our machines. English plows and threshing machines
also are, he states, preferred to all others; "but the Americans supply at a cliea])er rate
better horse-rakes, mowers, and reapers, with or without self-binders. As these are ex-
empt from duty, Russia does not attempt to enter into competition. It may seem strano-e "
Consul Stanley goes on to say, "that the American makers should so com])letely drive
the English out of the field in tliis business. An explanation given to me is that they
are content with a smaller profit than English makers, and that the iron and wood work,
while sufficiently strong, is lighter and better. English manufacturers could, I am told
make an equally good article, and the rate of skilled wages being less in England than
in America, the cost of making them ouglit to be less; but English makers, apparently,
do not care to .sell them at the price taken here for such articles of American make." —

Iron, London.

128

THE LOCOMOTIVE.

[August,

Incorporated
1866.

Charter Per-
petual.

Issues Policies of Insurance alter a Carelnl Inspection of the Boilers,

COVEKINtJ ALL LOSS OR DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

ARISING PROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full iuforniation conrerning the'plan of the Company's operations can he ohtained at the

Gonvnip^^isr'sr's oi^ipioE, m^ieTiFOiaxD, coisrisr.

Or at any Agency.

J. M. ALLEN, Pres't. W. B. FEANKLIN, Vice-Pres't. J. B. PIERCE. Sec'y.

Boai'cl or I>irectoi*s:

^Etna Fire Ins. Co.
Treas. Cheney Brothers

J. M. ALLEN. President.
LUCIUS J. IIENDEE, Prest
FRANK \V. CHENEY, Asst.

Silk Manufacturing Co.
CHARLES M. HEACH, of Beacli & Co.
DANIEL PHILLII'S, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Anier. Nat. Bank.
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Manufacturinfj; Co.
THOMAS O. ENDEKS, Sec'y. .Ktna Life Ins. Co.
LEVERETT BRAINARl), of The Case, Lockwood &

Brainard Co.

Hon. HENRY C. ROBINSON, Attorney at Law.

Gen. W. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire
Arms MfiT. Co.

GEO. CROMPTON, Cromptou Loom Works, Wor-
CGst cr

Hon. TH()S. TALBOT, E.K-Governor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manufacturer, Provi-
dence, R. I.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. PARRY, of Baldwin Locomotive Works,
Philidelphia.

GENERAL AGENTS.

THEO. H. BABCOCK,
CORBIN& GOODRICH,
LAWFORD & McKIM,
W. S. CHAMBERLIN,
J. L. SMITH.
H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FREEMAN,
W. G. LINE BURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

CHIEF INSPECTORS.

OFFICES.

R. K. McMURRAY,

Nkw York City.

Office, 285 Broadway. ■

WM. G. PIKE,

Philadklphia.

430 Walnut St.

JOSEPH CRAGG,

Baltimore.

10 So. Holliday St

WM. U. FATRBAIRN

Boston, Mass.

10 Pemberton Sq.

B. M. LORD,

PROVIDf:NCE, R

1.5 Weybosset St.

H. D. P. BIGELOW,

Chicago, III.

t (

115 Munroe St.

J. S. WILSON,

St. Louis, Mo.

4 i

404 Market St.

F. S. ALLEN,

Hartford.

218 Main St.

J. H. RANDALL,

Bridgeport.

328 Main St.

A. C. GETCHELL,

Cleveland.

246 Superior St.

J. S. WILSON,

Cincinnati.

53 West Third St

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series— Vol. III. HARTFORD, CONN., SEPTEMBER, 1882.

No. 9.

An Explosion Without Any Mystery.

The explosion illustrated in this number of the Locomotive occurred some years
ago in one of the southern cities. A short account of the accident appeared in the
LocoMOTiTE at the time, and we reproduce it here with an additional illustration, which
shows more clearly the cause of the disaster, believing it will afford a timely warning to
workmen who have occasion to make repairs to boilers, as well, also, as to illustrate
certain important points regarding the proper construction and arrangement of safety-
valves.

Fi(i. 1.

The exploded boiler was one of a battery of two horizontal boilers, 48 inches in
diameter by 31 feet long. Each boiler had two flues 16 inches in diameter by 27 feet
long. The thickness of the shell plates was ^ of an inch. They were provided with
domes 20 inches in diameter, to the top of which the steam-pipes and safety-valves
were connected as shown in Fig. 2. Each boiler was provided with its own safety-
valve, with no stop-valve between it and the boiler. The two boilers were run in con-
nection with each other, and were connected with each other by a steam pipe provided

130

THE LOCOMOTIVE,

[September,

with a stop-valve, which could be closed when it was desired to use but one of the
boilers. The working pressure allowed was 60 pounds per square inch.

The boiler which exploded was known as No. 2. Repairs being necessary, this
boiler was laid off, and the stop-valve between it and No. 1 was closed. This valve
leaked slightly, and the steam coming through from No. 1 was condensed in the pipe
and dripping down through the opening in tlie dome and annoyed the workmen who
were making the repairs (and who were inside the boiler), so one of them made a pine
plug to fit the hole in the steam-nozzle, and drove it into tlie nozzle from the inside, as
shown in Fig. 2, and went on with his work. When the repairs were completed, the
I . workmen of course got out of their vmcomfortable quarters as

^^ quickly as possible, and, what was very natural under the cir-

— cumstances, forgot all about the plug, it he\ng at the top of the
dome out of sight. They then put on the man-hole plate, and
pronounced the boiler ready for use.

Thus it will be seen that the only outlet for the steam was
securely closed, and the safety-valve rendered useless.

The boiler was filled with water and the fire started under
it. Four hours afterward it exploded with great violence,
demolishing everything in the immediate vicinity, killing one
man and injuring several others. The damage to property was
estimated at not less than 15,000 dollars.

A study of the top of the dome of the exploded boiler is
very' interesting. The crown of the dome was of cast iron and
was 1 1 inches thick. It was convex outwardly, and the steam
nozzle was cast with and formed a part of it. It will readily be
seen that the force required to produce the rupture must have
been enormous. The surface of the iron through the line of
fracture shows it to be sound and of good quality. The portion of the plug left project-
ing into the dome by the workmen was about 8 inches long, and 3;^ inches in diameter.
It was completely shattered or "broomed'' by the force of the expanding steam. It
appears as though the steam, under the immense pressure just preceding the explosion,
had permeated the fiber of tlie wood, and filled every Dore, and its sudden exiwnsion
when the boiler burst and the pressure on it was relieved, was sufficient to completely
shatter the projecting portion. It has the same appearance as portions of a tree have
which has been struck by lightning, and the moisture in it .'suddenly converted into
steam of sufficient tension to splinter the trunk.

Workmen cannot be too careful when making repairs on steam boilers, or any
changes in steam connections, to be perfectly sure, the last thing they do before putting
on the man-hole cover, to see that the outlet to the safety-valve is free from all obstruc-
tions. The importance of this cannot be overestimated. Under no circumstances
should it be plugged up as it was in the above case, for there is always a chance that it
may be forgotten to remove the plug, and then serious consequences are sure to
follow. The most careful workman is apt to forget to do so in the rush and hurry under
which such repairs are generally made, and therefore the risk of doing so sliould necer he
incurred. •

It is also very bad practice to make the safety-valve part of a cluster of fixtures
or mounting, as it was in this case. It should always be an independent fixture, and
have its own independent connection with the boiler. Then the risk of accidents like
the above will be reduced to a minimum. Had the safety-valve on the above boilers
been properly mnatructed^ the accident would never have occurred.

Fig. 2.

1882.]

THE LOCOMOTIVE,

131

Inspectors' Reports.

JuLT, 1882.

The summary of the one hundred and ninetieth monthly report of the Inspection
Corps is given below, and has more than the ordinary amount of interest to boiler own-
ers and users. From it we learn that the inspectors of the company made 2,071 visits
of inspection, and examined altogether 4,838 boilers. 2,523 of these were complete in-
ternal and external inspections, while 373 were subjected to hydrostatic pressure.

The number of defects found foot up 8,081. of which number 455, or about 14f per
cent, were considered dangerous. The number of boilers condemned was 54. Below
is a tabular view of the number of defects of each class found.

Xature of defects.
Cases of deposition of sediment.
Cases of incrustation and scale,
Cases of internal grooving, - - - -

Cases of internal corrosion, -

Cases of external corrosion, - - - -

Broken and loose braces and stays, -
Defective settings, -----
Furnaces out of shape, - - - .

Fractured plates. -----
Burned plates. . - - .

Blistered plates, . . . _ .

Ca.ses of defective riveting, - - - -

Defective heads,
Cases of leakage around tubes.
Cases of leakage at seams, -
Water-gauges defective.
Blow-outs defective, -
Cases of deficiency of water,
Safety-valves overloaded,
Safety-valves defective in construction,
Pressure gauges defective, -

Whole numb

er.

Dangerous.

335

585

113

200

106

158

332

311

205

163

174

Total

3,081 - - 45i5

It seems strange that in the present advanced state of the mechanic arts, there can
be found men who will tit up safety-valves in the manner in which we sometimes find
them. In many cases the grossest ignorance of the first principles which should govern
the construction and arrangement of apparatus of this sort is displayed. In other cases
it would be hard to determine whether ignorance, carelessness, or cupidity is responsible
for some of the astonishing work which we run across.

One favorite way of running the escape pipes of safety-valves where boilers are sit-
uated in buildings not over one story high, is to run it straight up through the roof of
the Vjuiiding. This is perhaps well enough if tlie couuections are properly made and the
pipes properly drained, but unless they ar^ furnished witii a properly arranged drip-pipe,
the arrangement is positively dangerous, and should never be allowed under any pretense
whatever. In fact no escape-jtipo should rise in tl)e slightest degree after it leaves the
valve-chamber without being provided with a drip-pipe. It will invariably fill with
water if it does, and this will, of course, increase tlie load on the valve, and the water
which so collects, not only corrodes the valve and its fittings, but it is very liable to be-
come frozen in the winter season, and disaster is sure to follow if it does.

132 THE LOCOMOTIVE. [September,

One of the most damaging' explosions on record occuired a few years ago from this
cause. Tlie pipe run out through the side of the building and some distance beyond.
It became filled with water, which froze up solid, in consequence of which the boiler
blew up from failure of the safety-valve to relieve the pressure.

Another way of putting up escape pipes from safety-valves is to run them irtto the
chimney or the flue which leads to the chimney. This is frequently resorted to when
the chimney power is deficient and the reason given for it is that '• it improves the draft."'
It is difficult for a disinterested person to see how this device operates to " help the draft "
unless the valves are blowing off steam, and we confess our inability to see why the draft
should be improved at that time. However, we suppose a poor apology is sometimes
better than none at all.

One potent reason why safety-valves should never be put up this way is this: It is
impossible to tell when a valve is tight when it is connected. It may leak, and become
a source of great waste, without anyone knowing anything about it. A valve should
never be ptit up so that any leakage of steam Avill fail to make itself manifest imme-
diately.

Safety-valves should never have an "escape-pipe" attached to them. They should
be allowed to blow freely into the boiler-room. The objections to this plan are fast dis-
appearing among intelligent steam users and engineers, and in the very best arranged
boiler-houses that have been built lately, the safety-valves are i^ut up in this manner.
This arrangement is not only the best, but it is also the cheapest, as all the extra pipe-
fittings and useless labor are saved.

There can be little doubt that it would have been a blessing if the ordinary lever
safety-valve had never been invented. If the inventor's design had been to make some-
thing possessing every facility for being tampered with, instead of making a safety-valve,
he could not have succeeded in a more admirable manner. The lever offers every facility
for overweighting at the caprice of an ignorant or careless boiler attendant. If more
steam is wanted, if, from any cause, the demand for steam is irregular, so that much care
is required to prevent often blowing off, or, if the valve leaks, the sovereign remedy is to
slide the weight out farther on the lever, or attach all manner of junk to save trouble.
And observe bow admirably the thing is contrived to produce much overweighting with
little effort. The multiplying principle of the lever is Wrought into requisition so that
a pound on the end of it may be equal to anywhere from five to ten pounds on the valve,
and the effect of hanging a few old bricks, gears, pulleys, or pieces of anything tliat has
weight, on the end of the lever, would be equal to a whole junk shoj} if placed directly
on the valve. And the lever is such an inviting place to hang scraps of all kinds, that
many boiler attendants are simply unable to resist the temptation to do so on the slight-
est provocation.

A really good safety-valve should possess the following qualities in the highest pos-
sible degree:

First; It should be of the "dead weight" type of construction. No steelyard lever
should be allowed in its construction, it would then require much more weight placed
on it to produce a dangerous degree of overloading.

Second ; Its construction should be such it would be no easy matter to place extra
weight upon it, and such that any extra weight could be readily seen by anyone.

Third ; It should be connected to the boiler so as to be easily accessible, and no
escape pipe should be connected to it, and it should be arranged so as to be easily lifted
once or twice a day by the attendant.

Fourth ; It should always be an independent fixture, attached directly to the
boiler, and should have no connection whatever with any of the other fittings on the
boiler.

1882.] THE LOCOMOTIVE, 133

Mkt Btttmttint*

HARTFORD, SEPTEMBER, 1882.

Co.MPARATiTELT few people except those particularly interested in natural science
are aware of the important work which is being accomplished h\ the United States Fisli
Commission.

Its object is to thoroughly investigate and study the sea fauna of the waters of our
coast. In the winter season its labors are mainly confined to our southern waters,
while in the summer its investigations are extended to and largely confined to the Xew
England coast. Its summer station is at Woods" Hole, Mass., the southern point of the
promontory that divides Buzzard's Bay from Vineyard Sound. Here may be found the
Laboratories, Aquaria, and manipulating rooms of the commission, while at an ad-
joining wharf is a large steamer named " The Fish Hawk," which is used exclusively by
the commissioner for dredging in the adjacent or more remote waters for " life beneath the
waters. "" The steamer is provided with very complete apparatus for dredging in deep waters,
and sometimes the "catch" comprises beautiful and rare specimens. These dredgings
are not unfrequently made in waters 800 fathoms deep. From these great depths fish
unheard of before are often brought to the surface, and it is interesting to note that their
eyes are generally undeveloped, little more than rudimentary — apparently sightless —
showing that very little light penetrates these great depths, and yet there is animal life, a
fact which these and .similar investigations have established, though until within a few
years it was thought impossible for animal life to exist so far below the surface. When
the "catch" is brought in it is examined and distributed in the several aquaria, where
the habits of the various species can be studied.

The rare ones are then preserved in alcohol and prepared to enrich the already large
and rare collection in the National Museum of the Smithsonian Institute at Washington.
The work of this commission has settled many important questions bearing upon the fish
supply of our coast, their habits and feeding grounds, and the intelligent and scientific
manner in which the work has been done, has given it high rank among similar commis-
sions of other nations. It is highly creditable to our national goverment that it pro-
vides liberally for such investigations.

This commission is under the direction of Prof. Spencer F. Baird, Secretary of the
Smithsonian Institute. His name at the head is a guaranty that all the investigations
will be conducted in the most scientific manner. Prof. Baird is not merely a figure-head ;
he is on the ground and supervises every detail. He is ably assisted by an enthu.siastic
corps of naturalists, among whom are Profs. Verrill and Smith of Yale Scientific school.
Prof. Smith of New York, Prof. Rathbun of the Smithsonian Institute, Dr. Kidder,
and many others. Captain Tanner is commander of the "Fish Hawk.' He is not only
highly competent in nautical science, but enters with enthusiasm into the whole work of
the commi-ssion. It has been our privilege to spend more or less time with these gentle-
men, each season for several years, and we esteem it one of the great privileges of our
lives, it opens a wide field for thought, and gives new impressions and views of the
handiwork of that ever active Providence that provides for all His creatures.

134 THE LOCOMOTIVE. [September,

We are glad to notice that the American Railway Master Mechanics' Association
lias taken the first step towards abolishing the use of that trade idiocy known as win; and
sheet metal gauges. How anything of the sort ever was originated is a complete puzzle
to us, and now that instruments for measuring with precision are everywhere used, an
adherence to anything of the sort shows still greater stupidity. The only way that we
can ex])lain the existence of the abomination is on the supposition that people always
used to measure in the same manner as the laborer, who, when given a two-foot rule and
told to go and measure a certain dimension, returned with the information that it was
" twict the length of the rule, the thickness of two bricks and ' a small bit of a schtick,'
the breadth of two fingers, and half the distance from his 'fisht' to his elbow." Appear-
ances indi(;ate that wire gauges originated from some such standard as this.

The list of horrors traceable directly to the use of a poor quality of kerosene oil is
so great that few ])eople have any idea until they have made investigations. Accidents
by burning are really the most terrible which can happen to people, and those who suffer
most from the use of poor oil are those whose sensibilities are the keenest, the accidents
usually happening to women and children. We think there is little need of an oil accident
of any kind when a good quality of oil is used. Unfortunately, public taste, when oil first
came into the market, was made the sole judge of its excellence. People had been in
the habit of burning camphene and other similar substances which were "water white."
Without knowing what constituted a good oil, people at once began to demand a white
kerosene, because they " didn't like the looks " of the yellow oil. In England even the
better qualities of American oils have on more than one occasion been condemned by
consumers as being bad, simply on account of their dark color and great specific gravity.
Our manufacturers were actually sending them an oil that was too good. It was heavy,
and consequently when the reservoir became partly empty, the wick had difficulty in
lifting it to the flame. In their ignorance they wanted something which was lighter,
which burned easier, and was of course more dangerous. — Mechanics.

Standard for Exact Measurement.

The committee appointed by the American Society of Mechanical Engineers at the
meeting held in Philadelphia April last to investigate the method adopted by the Pratt
& Whitney company for the establishment of a standard for exact measurement, and
which met recently at the works of the company, was composed of the following gentle-
men : Henry Morton, Ph.D., president of the Stevens Institute, Hoboken, N. J., chair-
man ; J. Sellers Bancroft, of William Sellers & Co., Philadelphia, secretary ; Professor
Robinson of Oliio state university ; Oberlin Smith, president of the Ferracute Machine
company, Bridgeton, N. ,1. ; William Betts of the Betts Machine company, Wilmington,
Del.; George Stetson of Morse Twist Drill company, New Bedford; Ambrose Swasey of
Warner & Swasey, Cleveland, O. ; Edward Parkes of the Brown & Shaip Manufactur-
ing company, Providence, R. I., and Charles T. Porter of the Southwark Foundry and
Machine company, Philadelphia. Their report is to be submitted at the next meeting of
the mechanical engineers' society, to be held at New York in November.

A very favorable report has already emanated from the committee appointed by the
car builders' association of the United States, resulting in the adoption by them of the
United States standard thread gauges produced by the Pratt & Whitney company.
The subject of exact measurement has been most carefully considered by the company
during the past three years, and has been carried out from a scientific foundation to a
practical woi-kiiig standard irrespective of what has been done by others, the British

1882.] THE LOCOMOTIVE. 135

imperial yard being the only reference, an accurate transfer of which is in the hands of
the company. A complete and detailed description of the work and apparatus em-
ployed, with reports, etc.. will soon be published. This comparator meets a long-felt
want among machinists and will probably be universally adopted. The scientific work in
obtaining the necessary transfers and the determination of the co-efficients of expansions
was performed by Professor W. A. Rogers of Harvard observatory, Cambridge, Mass.,
and his plans were originally carried out in the construction of the comjiarator now in
use by the Pratt & Whitney company. Mr. George W. Bond has been in charge of the
work throughout — a work w'hich appears to have given satisfaction to the scientific
gentlemen who have had the privilege of seeing it in operation. — Hartford Post.

A London Anaconda.

A few years ago an immense anaconda, or water-boat, was received at the Gardens
in Regent's Park, brought in a barrel on board a steamer from Central America to Liver-
pool, and fowarded thence by rail. This reptile is the largest of the serpent tribe, in-
habiting the swamps of tropical America, and sometimes attaining a length of thirty or
forty feet, it may be much more. It is one of the constrictors — that is to say, it is non-
venomous, and kills its prey, like the boa and python, by crushing it within the convo-
lutions of its powerful body. In the British Museum there is a fine stuffed specimen,
about thirty feet long, represented in the act of seizing, though not constricting, a peccary.
The subject of my tale measured twenty-three feet in length, and in girth was equal to
the circumference of a man's thigh — a formidable customer, capable of swallowing a
sheep. Prepared for his reception, with the floor duly graveled, and a tank with water.
Den No. 3, on the left-hand side of the reptile-house, counting from the entrance door,
was allotted to him; and within the cage is a stunted tree, up which these large serpents
are wont to climb. The top of the cask unscrewed, the creature was allowed to find his
way into the cage through the small aperture behind.

Roaming about in the full enjoyment of his new-found liberty, he presently turned
round between the tree and front of the cage — a space of several feet — in such a way
that the l)ight of his body — to use a seafaring expression — lay within this space. Here,
feeling the contact of the glass on one side and tlie wood on the other, he suddenly
expanded his coil, probably in the sheer luxury of being able to stretch himself, and
pushed the front of the cage out! Not simply the glass, itself, which was not broken,
but the heavy framework in which it is fixed, was forced away from its connection with
the siuTOunding beams. Hereupon several of the spectators had the presence of mind
to rush forward and catch the sash before it could fall to the floor. In this way they
supported it as well as they could with hands and knees luitil fresh assistance arrived,
for the weight was to great for them to lift it back into position again; while the rep-
tile inside, excited by the shouting and commotion, was dashing about furiously in all
directions. This scattered the gravel about; and it was then found impossible to return
the frame into its proper place, as the groove was choked with the small stones. Mr.
Frank Buckland, aided now by a number of men from all parts of the gardens, still ke]it
the glass from descending, while the kee{)er and carpenter, who got into tiie cage from
behind, having thrown some blankets over the snake and puslied him into a corner, pro-
ceeded to scrape away the gravel. But the anaconda, now thoroughly enraged, contrived
to extricate his head from the covering, and before the men could escape, flew at the car-
penter and seized him by the shoulder. Tlie keeper courageously turned, gripped the
serpent by the throat, and forced him to let go, but not until the unfortunate man's arm
was terribly lacerated by the powerful lancet-like teeth.

136 THE LOCOMOTIVE. [September,

Luckily, the door of the reptile-house had been locked when the first contretemps
took place, so that no casual visitors were witnesses of the scene; otherwise fainting
women and horror stricken-men would doubtless have added to its confusion. By this
time the groove was clear, and the frame temporarily secured, so that the carpenter made
good his e.xit, while the keeper watching his oppoitunity, flung the creature from him
and jumi^ed out.

But it afterwards became very tame and tractable, and I established very friendly
relations with it. Many a time have I stood at the door with Holland, the keeper, and
allowed it to rear its great black-spotted head out of the tank till it flickered its tongue
against my face, Avhile I patted its shining scales with my hand. Towards Holland it
was most affectionate, and would always come up to the grated ventilator to see him
when he was sweeping out the passage behind, though it took no notice of the people
in front. Snakes take strong likes and dislikes to people, often unaccountably.
Holland was one of the kindest and most intelligent keepers that ever handled a reptile,
and could generally win any thing's confidence; yet there Avas — and probably is still — a
West African python, some sixteen feet long, in the house, that positively conceived a
murderous hatred of him. Why this should be so, neither he nor any one else could
ever understand; but it is a fact that this python at feeding-times would sit up close to
the d<5or and wait, not for the ducks and rabbits, but for him I — Chanibers' Journal.

London Fire Service. — Capt. Eyre M. Shaw, Chief of the London Fire Depart-
ment, now visiting this country, gives a number of interesting facts with regard to the
system and material for fire protection in use in London.

The area to be protected is 131 square miles. The force employed numbers 536
men and officers of all grades, one-third of the number doing duty by day, and two-
thirds by night, each set working twelve hours. The equipment of the department
comprises 53 land fire engines, 121 fire escape engines, 3 floating steam fire engines,
11 movable land stations, 4 floating stations, 3 large land fire engines, 35 small steam
land fire engines, 2 steam tugs, 4 barges, 29 hose-carts, 15 vans, and two trollies.

The movable land stations are large vans that are taken to a designated spot every
night at eight o'clock, each one drawn by four horses. The horses are then returned to
the engine-house to which they belong. They are sent the next morning at eight o'clock
to fetch the vans back. In each van is an engine and a number of men who are always
ready to attend a fire in the immediate neighborhood where the van is stationed. The
department is forced to use these movable stations on account of the cost of building
permanent stations. The engine does not leave its place, but depends upon its length
of hose to reach a fire.

The system of telegraph alarms has fifty-three telegraph lines with forty-four "call
points," or alarm -boxes, and seven telephone lines. The intention is to replace all the
telegraph lines with telephone lines. The city is divided into four sections or fire dis-
tricts, each with a central office, communicating with headquarters. The area covered
is so great that a single system, like that of New York, would not answer.

Captain Shaw was greatly interested with the method employed in this city of
loosing the horses from their stalls by electricity on the sounding of an alarm, and the
automatic harnessing. The London horses stand in their stalls harnessed. All the
London fireman are given a two months' course of instruc tion and systematic drilling
before they are sent out for actual service. The department has discarded rubber hose
entirely and use "fabric hose," which is much lighter, costs one-third as much, and
last three times as long. It is manufactured at Dundee. — Scientific American,

1882.]

THE LOCOMOTIVE.

137

Table Showing" the Number of Rivets in 100 Pounds.

DIAMETERS.

Length. | iucli.

iiifli. i inch.

^^g inch.

I inch.

inch.

I inch. I inch.

1965

1419

1848

1335

1692

1222

1512

1092

1437

1036

1368

988

1300

949

1260

924

1200

900

1156

840

1100

789

1031

744

999

721

945

682

900

650

828

598

779

562

743

536

715

513

4i-

1093

1027
940

944

846
763

840

726

797

691

760

653

730

624

711

596

693

553

648

532

608

511

573

502

555

491

525

475

500

443

460

411

433

379

413

352

395

341

326

312

298

284

270

256

244

233

223

213

207

203

198

665
597
538
512
487
460
440
420
390
375
360
354
347
335
312
290
267
248
241
230
220
210
200
190
180
172
164
157
150
146
143
140

450
415
389
370
357
340
325
312
297
289
280
260
242
224
212
201
192
184
177
171
166
161
156
151
145
140
138
134
129
125

356

228

329

211

280

180

271

174

262

169

257

165

243

156

237

152

232

149

220

141

208

133

197

127

180

115

169

108

160

102

158

150

146

138

135

130

124

120

115

111

107

104

100

Tlie lengtli of rivets required for hand driving = the icngtli of the hole + 1^ times
the diameter of the rivet.

The lengtli (jf rivets reijuiretl for mnchine drivimj ~ \i times the length of the hole
+ 1^ times the diameter of tlie rivet.

The weight of a ])air of rivet heads is about as follows:
Diameter of rivet,
Weight of two heads, . . . ~ ^, \

5" 11" 3" 1"
H > l5 ) 4 ) «

of a pound.

A Singular Sub.ject. — The question whether our heads are smaller than those of
our grandfathers has been attracting particular attention in European scientific circles
during the last few weeks. The suljject was first agitated by writers for Nature, Lon-
don, one of whom, Mr. F. F. Tuckett, insists that the average size of liats has decreased
one size within the last twenty-five years, which means, if the criterion is to be trusted.
a diminution of three-eights of an inch in average circumference. As Mr. Tuckett
adduces in evidence of his assertion the testimony of leading hatters in London, he is

38 THE LOCOMOTIVE. [September,

probably riglit, says the New York Times, so far as that part of the case is concerned.
But there are, as Mr. Cliarles Roberts explains, in a rejoinder to Mr. Tuckctt, various
reasons for the average decrease in size of hats, without accepting that gentleman's view
of the cause. In the first place, men wear their hair cropped more closely than they did
years ago; and in the second, the fashion now is to wear one's hat on the top of the
head, instead of ]nilling it down over the ears, as was done by men of the last genera-
tion. Again, the tall hat is now worn by a large class of persons who are uniformly
small-headed, such as clerks and shopmen, who formerly did not effect such a luxury;
while on the other hand, many persons of the large-headed class, clergymen and others,
■who wore tall hats only years ago, have now given them up, and ]M-efer the soft felt to
the uncomfortable section of stovepipe once in vogue. The only way to get at the
truth would be to examine the statistics of each class separately, and to make an allow-
ance of a quarter of an inch for tiie present mode of wearing the hat and of cropping
the hair. But if Mr. Tuckett's view is to be accepted, then, while the head has lost in
size, there has been a general gain in weight and vigor of body; for, comparing the sta-
tistics of factory children in 1833 with those of 1873, in England, it is found that chil-
dren of ten years of age now are as tall of statue and as heavy as children of eleven
years of age were forty years ago. There is great variety, however, in the size of heads
among the intellectual classes in England. According to Mr. Tuckett, Lord Chelmsford
wears a 6|- hat only ; and the sizes of some prominent people he gives as follows : The
late Dean Stanley, 6| ; Lord Beaconsfield, 7; the Prince of Wales, 7; Charles Dickens,
7^; Lord Selbourne, 7^; John Bright, 7^; Lord Russell, 7^; Macaulay, the historian,
7f ; Mr. Gladstone, 7|; Thackeray, 7|; Louis Philippe, 7f ; M. Julien, the celebrated
musical conductor, 7J; and the Archbishop of York, 8. The prelate must possess a
head of nearly 24 inches in circumference, while that of Dickens was average, that of
Thackeray beyond the average, and the pumpkin-head of Louis Philippe Avas very
large. — Exchange.

Visitors to ancient wine vaults or damp coal pits are sometimes astonished l)y the
curious fungi which drape the walls with gruesome tapestry ; but every instance of this
kind is thrown into the shade by the extraordinary growtj|B which have recently been
discovered in some of the deserted Mexican silver mines of Nevada. Tlie dank, warm
timber galleries and drifts of these old workings abandoned to themselves for years,
have silently given birth to a monstrous brood of morbid vegetation which, apparently,
has no ])arallel in the regions of the sunlight and the ujjjier air. In general they are all
of a snowy whiteness, and some of the hooded masses rise \i]) several feet from the
ground like sheeted ghosts. Others, in the distance take the form of bearded goats or
sleejnng owls. Here great bunches of long, white hair hang down from the roof; and
there huge, pulpy masses encumber the floor like brimstone coral. The latter appear to
have sprung miraculously from some spilled upon the rocks in past days, while the
former seem to have crystallized like hoar-frost from the atmosphere itself. Some of the
round masses have acutally lifted up from tlie floor blocks of stone weighing ten, fifty,
and even one hundred pounds to a height of three feet. In the higher level of the mines,
where the air is drier, the fungi are far less bulky then below, and much firmer in texture.
The shapes here are, however, more beautiful. One kind grows in a twisted spiral like
a rams horn to a length of five feet, and hangs from the rafters like a trophy of the
chase, or rather, like a serpent suspended by the tail. Another sort sends out A stem the
thickness of a pencil to a height of one or two feet where it blossoms into a bulbous
knob something like a flower. Nothing like the toadstool or the common mushroom is
to be found, and the wondrous growths have all the aspect of being called into a
special being by the pecularities of their environment. — Exchange.

1882.]

THE LOCOMOTIVE.

139

Table of Inches and Sixteenths Reduced to Decimals of a Foot.

The followiug table will be found of very great use to draughtsmen and others who
have a varietj- of computations to make :

luch.

]

Feet.

Inch.

Feet.

Inch.

Feet.

Inch.

Feet.

Inch.

Feet.

Inch.

Feet.

.0000

.1667

.8333

.5000

.6667

.8383

.0052

.1719

.3385

.5052

.6719

.8385

.0104

.1771

.3438

.5104

.6771

.8438

.0156

.1823

.3490

.5156

.6828

.8490

.0208

.1875

.3542

.5208

.6875

.8542

.0260

.1927

.3594

.5200

.6927

.8594

.0313

.1979

.3646

.5313

.6979

.8646

.0365

.2031

.3698

.5365

.7031

.8698

.0417

.2083

1 *

.3750

.5417

.7088

.8750

.0469

.2135

.3802

.5469

.7135

.8802

.0521

.2188

.3854

.5521

.7188

.8854

.0573

.2240

.3906

.5578

.7240

.8906

.0625

1 4

.2292

.3958

3
4

.5625

3
4

.7292

3
4

.8958

.0677

.2344

.4010

.5677

.7844

.9010

.0729

.2396

.4063

.5729

7
8

.7396

7
8

.9063

.0781

.2448

.4115

.5781

.7448

.9115

.0833

.25

.4167

.5838

.7500

.9167

.0885

.2552

.4219

.5885

.7552

.9219

.0938

.2604

' i

.4271

.5988

.7604

.9271

.0990

.2656

.4323

.5990

.7656

.9328

.1042

.2708

.4375

.6042

.7708

J.
4

.9375

.1094

.2760

.4427

.6094

.7760

.9427

.1146

.2813

.4479

.6146

.7813

3
8

.9479

.1198

.2865

.4531

.6198

.7865

.9531

.1250

.2917

.4583

.6250

.7917

.9588

.1302

.2969

1 -

.4635

.6302

.7969

.9635

.1354

.8021

i i

.4688

.6354

.8021

.9688

.1406

.3073

.4740

.6406

.8078

.9740

.1458

.3125

.4792

.6458

.8125

.9792

.1510

.3177

.4844

.6510

.8177

.9844

.1563

.3229

.4896

.6568

1
8

.8229

7
8

.9896

.1615

.3281

.4948

.6615

.8281

i .9948

The annual expense of running a locomotive engine and tender, averaging 75 miles a

day for 267 days in the year, or 20,000 miles annually, is given as follows by Trautwine:

Fuel, say 2^ cords wood per 75 miles, at $3.50 per cord, $7.87^ per day, - $2,100

Repair, at 9 cts. ])er mile run, ------ 1,800

Engineer, 12 months, at $90 per month, . . . . . 1,080

Fireman, 12 months, at $50 per month, . . . . . COO

Oil and waste, at 1 ct. per mile run, ------ 200

Sawing and loading wood, at 1^ ct. per mile run, . . - - 30O

Supplying water, at 1 ct. per mile run, . . . . . 2OO

Putting away, cleaning, and getting out, say, - - - - - 120

Locomotive superintendence, ------- 100

Total, --.------ $6,500

Equal to 34 cts. per train mile; $24.35 per running day, or $17.81 for every day in
the year.

-140 THE LOCOMOTIVE. [September,

A Correspondent writing from Bayreuth, in describing a fire, says: — The night I
arrived I had the unexpected pleasure of seeing a comedy. It was a genuine Germnu
comedy, too. Its su])ject-matter was tlie efforts of the Bayreutli fire brigade to put out
a fire. I was awakened from a sound sleep by the loud locating of a drum under my
windows. I could hear drums beating in various parts of the city, the church bells were
ringing, there was a heavy tramp of soldiers through the street, people rushing
about and shouting '' Fire" — in fact every indication of a fire, except the noise of fire
engines. A house a little way down the street was burning. A crowd luid gatliered
there. I fouiul the infantry guarding a patch of beans, the cavalry stationed about the
potato patch with Hashing sabres, and the artillery drawn up around a pear tree. The
flames were crackling merrily among the beams. At last, around tjie corner appeared
six big Germans carrying a small ladder, and, after them, six small Germans earring a
big ladder. These twelve Germans wore green suits and brass helmets. When they had
managed to place the big ladder against the front of tlie house they ran away again.
After a wliile we heard a rattling as though a dog with a tin can tied to his tail was
running through the next street. The twelve Germans again turned the corner, drawing
after them what looked like a tin box on wheels. It was the fire engine — an open tin
box with a hand piunp. .V hose was attached. A fireman mounted the ladder.
Another fireman carried the hose up to him. Meanwhile, women with large wooden
paniers strapped to their backs brougiit water from the neighboring fountain and emptied
it into the engine. Finally, everything was ready, and tlie j^umping began. Several
large streams of water came from the joints of the hose and wet the bystanders. A
small stream came from the nozzle. The fire was such a trifle that they really managed
to get it pretty well under control. Then they consulted as to whether they should
adjourn then and there and get some beer or go on until the fire was completely out.
They decided to adjourn. In about an hour they came back and finished their work. I
heard one Bayreuther say to another that after all the Bayreuth fire brigade was the best
in the world. The next day the city council voted a resolution of thanks and a com-
pensation of 13^ cents to the women who carried the water from the foimtain to the
engine. During the " Parsifal " performances the firemen are distributed through the
theater. This seems to me unnecessary — the building could burn down without their
assistance. ^

Ekkect of Explosives. — In their sixth aniui;il i'c'})ort, (''i)lontl ^Lijendie and Major
A. Ford, the inspectors of explosives, say: — "Experiments conducted by us appear to
establish very satisfactorily that the cfl'ect of small charges of dynamite, and similar
explosives, upon masonry structure, is essentially local. Where the charge is in contact
with an external jjortion of the structure, any cfl'ect which may be produced is almost
entirely confined to a comjilete or partial penetration of the structure a\, the spot where
such contact occurs; while, if the charge be not in contact with any part of the struct-
ure, the result, in the case of an external explosion, is either wdiolly or nearly negative,
while, if occurring in the interior of a building, any effect which maybe produced is
limited to the more or less complete demolition of the chamber or portion of the struct-
ure in, or in the immediate neighborhood of whicli the explosion was effected. Gen-
eral, or even partial, destruction of a public building, or of a substantial dwelling-
house, could not be accomplished except by the use of very nuich larger charges of
dynamite and similar substances than could usually be brought to bear without attract-
ing observation, and the effect of a single 'infernal machine ' containing a few pounds of
explosive would be structurally insignificant." — Mechanical Warld.

1882] THE LOCOMOTIVE. 14^

The Razor-Back Hog. — To the traveler through Texas one of the strangest and
most peculiar features of landscape is the razor-back hog. He is of Swiss cottage style
of architecture. His physical outline is angular to a degree unknown outside of a text
book on the science of geometry. The country razor-back prowls around in tlic woods
and lives on acorns, pecannuts. and roots; when he can spare time he climbs under his
owner's fence and assists in harvesting the corn-crop. In this respect he is neighborly
to a fault, and, when his duty to the owner's crop will allow, he will readly turn in and
assist the neighbors, even working at night rather than see his crop spoil for want of at-
tention. Crossing the razor-back with blue-blooded stock makes but little improvement.
The only effective way to improve him is to cross him with a railroad train. He then
becomes an imported Berkshire or Poland-China hog, and if he does not knock the train
off the track, the railroad company pays for him at the rate of $1 a pound, for which
they are allowed the mournful privilege of shoveling the remains off the track. The
ham of the razor-back is more juicy than the hind leg of an iron fire-dog, but not quite so fat
as a pine knot. — Exchange.

A MUSEUM of relics collected by Mr. D. W. Sawyer, cashier of a bank at Boothbay,
Maine, contains, among other curious things, a piece of worm-eaten plank found in a
codfish, and a watch-chain taken from a cod on the Banks. A brown jug in the collec-
tion has this curious fish story. One of the crew of the schooner Willie G., at South-
port, accidently broke the handle from a jug and threw it overboard. Four weeks
afterwards, in that locality, while cleaning a codfish just drawn in, the fisherman ex-
claimed; " Wal, by gracious now, if I don't believe that here's the handle of my jug; ''
and, sure enough, the piece found in the cod fitted completely, and both are here to verify
it. — Exchange.

To Cleanse a Soiled Chamois Leathku. — ^lake a solution of weak soda and
warm water, rub jjlenty of soft soap into the leaf her, and allow it to remain in soak for
two hours; then rub it well until it is quite clean. Afterwards rinse it well in a weak
solution composed of warm water, soda, and yellow soap. If rinsed in water only, it
becomes hard -when dry, and initit for use. The small (|uantity of soap left in the leather
allows the finer particles of tlie leather to separate and become soft like silk. After rins-
ing, wring it well in a rough towel, and dry quickly; then pull it about and brush it
well, and it will become softer and better than most new leathers. — Boston Joiiriud of
Commerce.

Notes and Queries.

W. II. \V., Jr., Westville, (.'onn., asks: (1) Can you give nie a correct rule for deter-
mining the size of water-cylinder for pumps to supply a given size of automatic engine?
(2) What kind of grate bars are most suitable for burning wood and sawdust; the single,
the double, or the sectional? (3) If it is a fact (and I think it is ) that a steam boiler
evaporates more water some days than others to do the same amount of work, why is it ?

Ana. (1) From the known dimensions, speed of engine, point of cut off, and pressure
of steam used, calculate the amount of feed-water required per minute to supj.ly dry

142 THE LOCOMOTIVE. [September.

steam for the engine ; and then so proportion the pump that it will be capable of deliv-
ering at least 2^ times this quantity in a minute, if required. The manner of making
the calculation is best shown by the following

Exwnple. Engine with cylinder 80" diameter, 60" stroke of piston, cut-ofF at \ of
stroke, clearance 5 per cent., steam pressure 80 pounds above the atmosphere, 60 revolu-
tions per minute.

Area cyliiKlcr 30" diameter, —4.91 square feet, 5 feet stroke of piston. Then
4.91 X 5 = 24.55 cubic feet displaced by the piston at each stroke. If we divide this by
4 l)ecause the engine cuts oft at one-fourtli, and add the clearance, which is 5 per cent,
of 24.55, we obtain (24.55^4) + (24.55 x .05) = 7. 365 cul)ic feet of steam consumed by
the engine at each stroke. Multiplying 7.865 by 120, the number of strokes per minute,
we obtain 883.8 cubic feet of steam used per minute by the engine. Now one cubic foot
of water will make 282 cubic feet of steam at 80 pounds pressure (Bee Locomottve,
August, 1882, page 120), therefore we divide 883.8 by 282, and obtain 3.135 cubic feet
of fecd-wuter wliich must be supplied to the boiler every minute to supply the engine
with dry saturated steam.

But ^team from a boiler is rarely perfectly dry, more or less water is always carried
off with the steam — there is always some condensation in pipes and cylinders, and always
more or less steam lost by leakage, and water lost by blowing off; these quantities are
variable and cannot be calculated, therefore it is necessary to have a pump large enough
to supply more than the above quantity. Practice shows that it should be capable of
delivering at least 2^ times the above quantity. Hence, 3.135x2.5 = 7.8375 cubic feet
as the capacity of the pump per minute. The size of the water cylinder of such a pump
is quite arbitrary, and depends upon the speed at which it is run, and also whether it
is sin fie or double-acting. Good American practice would be to make the diameter of
the water cylinder for a double-acting pump about 4^ inches, length of stroke about 8
inches, and run it from 120 to 125 strokes per minute. If this is a plunger pump, the
suction may be throttled down so it will deliver the required quantity of water to the
boiler. If it is a direct acting steam pump, the speed of which can be varied at will,
the cylinder might be reduced in size, say 3| or 3^ inches in diameter, and 7-inch stroke.

(2) The sectional.

(3) The increased evaporation is probably due to the influence of the atmospheric
moisture upon the various belts and machines about the establishment, by which they
require an increased amount of power to drive them.

.1. C. A., New York, asks: For a rule for ascertaining the necessary weight and
length of lever for safety-valves on stationary boilers.

A)is. Referring to the Fig.,
W denotes the weight at end of lever in pounds.
L " " distance between center of weight
and fulcrum in inches.

w denotes the weight of the lever itself in pounds.
(J " " distance between center of gravity
of lever and fulcrum in inches.

I denotes the distance between center of valve
and fulcrum in inches.
V denotes the weight of the valve and its spindle in pounds.
A '• " area of valve in square inches.

P " " pressure in pounds jier square inch at which the valve compiences to
blow.

1882.] THE LOCOMOTIVE. 443

To find the weight required to load the valve for any given pressure, L, I, g, A, V,
and w, must be known. Then

](PxA)-,V+I^^)[ X /l (1)

Or, niultiplj- P by A and call the product a; then multiply w by g and divide the
product by I and add V to the quotient ; call the sum h.

Divide I by L and call the quotient c.

Subtract h from a and multiply the difference by c. The product will be the
required weight in pounds.

Example. Diameter of valve = 4". Distance from fulcrum to center of weijjht
— 36' . Distance from fulcrum to center of valve = 4". Weight of lever = 7 loounds.
Distance from fulcrum to center of gravity of lever = 15^". Weight of valve = 3 pounds.

What must be the weight at the end of the lever to make tlie blowing off pressure
80 pounds?

Area 4" valve = 13.566 square inches.

7 X 15 5
a = 80 X 12.566 = 1005.28 h= ^^ + 3 = 30.125. c = 4^36 = .lll.

Then (1005.28 — 30.125) x .111 = 108.3 pounds.

To find the length of lever, or distance from fulcrum at which the weight must be
placed for any required blowing oflf pressure, W, w, g, I, V, and A must be known. Then

L=|(PxA)-(V+[^)jxl m

Or, proceed as in the first case for the quantities a and b. For the third quantity, c,
divide the distance from fulcrum to center of valve by the weight. Subtract h from a
as in the first case and multiply the difference by c. The product will be the required
length.

Example. Take the same data as given in the above case. How far must the weight
be placed from the fulcrum to make the blowing off pressure 75 pounds?

Area 4" valve = 12.566 square inches.

7 X 15.5
rt = 75 X 12.566 = 942.45 h = ^ + 3 = 30.125 c = 4 -f- 108.3 = .037.

Then (1)42.45 — 30.125) x .037 = 33.7 inches.

To find at what pressure the valve commences to blow when the weight and its
position on the lever are known.

^ J (.. xg) + (LxW) + ^ ) _ A,

(3)

ExamjAe. Take the data in the first of the above cases, where w = 7, g = 15^, L = 36,
\V = 108, i) = 3, ; =4, and A = 12.566.

rrt , j (7 X 15.5) + (36 X 108.3) )

Then we have j '- i— --i + 3 j. ^ 12.566 = 80 pounds.

And in the second case where the weight is 33.7" from the fulcrum we have

(7 xl5.5) + 33.7 X 108.3) „ )

^ '—^ -^ + 3 - - 12.566 = 75 pounds.

]

F. S. K., St. Louis, Mo. Your figures are right so far as they go. You should take
into account the weight of lever and also the weight of the valve itself. See answer to
J. C. A., above.

144

THE LOCOMOTIVE.

[September.

Incorporated
1866.

Charter Per-
petual.

Issues Policies ol Insurance aller a Careful Insnectlon ol tlie Boilers,

COVERING ALL LUSS OR DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

ARISING FROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full information concerning the plan of the Company's operations can be obtained at the

<3(Dis/L:E>j^i>rir^s o:fi^io:hi, H:^^I^T:FOI^X), coisrisr.

Or at any Agency.

J. M. ALLEN, Pres't. W. B. FEANKLIN, Vice-Pres't. J. B. PIERCE. Sec'y.

ISoarcl ot J>li'ect<>i'!Si

.T. M. ALLEN. President.

LUCIUS J. HENDEE. Prest. JEtna Fire Ins. Co.

FRANK W. CHENEY, Asst. Trcas. Cheney Brothers

Silk Manufacturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Anier. Nat. Bank.
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Manufacturing Co.
THOMAS O. ENDERS, Sec'y. ^tna Life Ins. Co.
LEVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Gen. W. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire
Arms Mf<r. Co.

GEO. CRO.MPTON, Crompton Loom Works, Wor-
cester.

Hon. TIIOS. TALBOT. Ex-Governor of Mass.

NEWTON CASE, of Tlie Case, Lockwood & Brainard
Co.

WILLIAM S. SLATER, Cotton Manufacturer, Provi-
dence, R. I.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. PARRY, of Baldwin Locomotive Works,
Philadelphia.

GENERAL AGENTS.

THEO. H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKIM,
W. S. CHAMBERLIN,
J. L. SMITH,
H. D. P. BIGELOW,

C. C. GARDINEH,

D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILLY,

CHIEF INSPECTORS.

OFFICES.

R. K. McMURRAY,

WM. G. PIKE,

JOSEPH CRAGG,

WM. U. FAIRBAIRN,

B. M. LORD,

H. D. P. BIGELOW,

J. S. WILSON,

F. S. ALLEN,

W. S. FOX,

A. C. GETCHELL,

J. S. WILSON,

New York City.

PHir,.\DELPHIA.

Baltimore.
Boston, Mass.
Providence, R. I.
Chicago, III.
St. Louis, Mo.
Hartford.
Bridgeport.
Cleveland.
Cincinnati.

Office, 285 Broadway.
" 430 Wahiut St.
" lOSo. Holliday St.
" 10 Pemberton Sq.
" 42 Weybosset St.
" 11.5 Munroe St.
" 404 Market St.

218 Main St.
" 328 Main St.
" 246 Superior St.
53 West Third St.

9ffe

0r0m0fe.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series— Vol. III. HARTFORD, CONN., OCTOBER, 1882. No. 10.

A Defective Mud-Drum and what it Teaches Us.

Apparently trifling mechanical details which may easily be overlooked unless unu-
sual care is exercised by the constructor, sometimes have great influence on the efficiency
and durability of structures. This is especially true of steam boilers and their connec-
tions. A seam in the wrong place ; a single rivet in some particular place, badly driven;
a plate unduly strained in some spot; or an indentation in some portion of a boiler shell,
may. under certain conditions, which may develop in practice, but which may have been
more or less difficult to foresee, produce the most serious results.

The following communication lately received from 3Ir. J. H. Cooper of Philadel-
phia, aflFords a very good illustration of what sometimes occurs when some little detail
of a boiler is badly arranged, either through carelessness or otherwise.

Fig. 1.

Editor Locomotive: — I have recently noticed a mud-drum which has been re-
moved, and which shows evident marks of burning at the tops of the outside courses of
plates. (See Fig. 1.) These places were so badly burned that they leaked, and were
patched on the outside. This, of course, increased the difficulty two-fold, and only ren-.
dered the patch liable to more rapid destruction, which proved the case. It soon
raised a blister and led to removal of drum.

The destruction of the iron in this drum is so distinctly marked that my attention
was drawn to it in walking past simply. I thought the drum was condemned on account
of internal corrosion and pitting, which perhaps it was, but the top burning from con-
fined steam was sufficient to reject this member at once.

It would be better to make these drums without circular seams, or with middle ring
outside of the others. Yours respectfully, J. H. Cooper.

The accompanying cuts illustrate the above point. Fig. 1 is a section of the drum
which was burned on the top of the two outside courses of plates. It will readily be
seen that when the drum is filled with water, a portion of the contained air will be
trapped in the space at either end below the top of the inside course of plates. When
the fires are started, the air contained in the feed-water will gradually be expelled by the

146

THE LOCOMOTIVE.

[OCTOBEK,

heat, and will rise and entirely fill these spaces. Thus the sheets at these points will be
unprotected by water, and, being exposed to the full heat of the furnace, will become liighly
overheated, and be sure to buckle or blister, and be destroyed in time. After steam com-
mences to form, these places will be filled with a mixture of air and steam, which effect-
ually prevents contact of water with the plates as long as the fires are kept up.

Fig. 2 shows the proper construction. Here, the neck connecting the drum with
the boiler is located at the highest point of the drum, and no collection of steam and air
is possible. It is also well, where mud-drums are used, to watch them closely and not
allow one end to settle appreciably below the other end, or the same trouble will be
experienced.

^5v.

ssc

Fig. 3.

Some kinds of boilers having an internal furnace or combustion chamber, are so
constructed that they are peculiarly liable to the above defect. When they are provided
with a handhole at the lower side of the front end (as they always should be), opening
into the water space between shell and furnace, it becomes necessary, to gain room for
the handhole when the water space is narrow, to bend the furnace-plate upward. This
is generally done in such a manner that it forms a " bump " in the furnace sheet at its
•lowest point. This bump makes an excellent steam trap, and we find that it invariably
'blisters and burns out in a short time. The proper m^hod of construction in such a
case, would be to flatten the furnace sheet instead of making a hollow place in it. This
would be equally easy to construct, and would entirely obviate the above-mentioned
difficulty.

The action of the air and steam in the above cases, may be very prettily shown as
follows. Fill an ordinary kettle, or other similar vessel, with cold water, and invert a
deep watch glass in it. The watch glass must be inverted while it is entirely submerged,
so that no air will remain under it. Let it be fixed by means of any suitable apparatus,
so that it is three or four inches from the bottom of the kettle, and heat applied. Air
bubbles will soon begin to collect on the sides of the kettle and glass. At about 150 de-
grees F. the small air bubbles on the under or concave side of the glass will begin to run
together quite rapidly, and form one large bubble at the highest point of the glass before
the boiling point is reached. When the water begins to boil, steam rapidly collects be-
neath the glass, and usually a few seconds suffice to entirely expel the water from it.
After this small puffs of steam escape from beneath the glass at irregular intervals, but
never enough to allow the water to enter the glass to any apprecial)le extent.

This experiment represents exactly what occurs in a steam-boiler, whenever there is
an inverted "pocket" of any sort below the water level. It will readily be seen that
where the convex side of the pocket or lump is exposed to the furnace heat, as is the
case with a mud-drum, or where it is at the bottom of a furnace or combustion chamber,
it must inevitably l)ecome burned and destroyed.

1882.]

THE LOCOMOTIVE. 147

Inspectors' Reports.

August, 1882.

During the month of August last, there were made by the Inspectors of this Com-
pany, 2,026 visits of inspection. The total number of boilers examined was 4,809, of
which number 1,660 were thoroughly examined, both externally and internally ; the
remaining 2,649 were quarterly inspections or "externals" as they are denominated by
the inspectors, made while the boilers are under steam ; for the purpose of testing pressure
gauges, ascertaining the condition of safety valves, water gauges, blow-off connections,
feed° connections, and making suggestions in management relative to economy or safety.
The number of boilers which were tested by hydrostatic pressure was 402, principally
new ones tested in the yards of their makers for the purpose of ascertaining the quality
of their workmanship,' etc. The number of boilers condemned was 25. The whole
number of defects found foot up 2,637, of which 519 were considered to be of such a
serious nature as to impair the safety of the boilers in which they were found. The
usual tabular statement of defects is given below.

Nature of defects. Whole number. Dangerous.

Cases of deposition of sediment, . - - -

Cases of incrustation and scale, . - - -

Cases of internal grooving, - - - - -

Cases of internal corrosion, - - - - -

Cases of external corrosion, - - - - -

Broken and loose braces and stays, - - - -

Defective settings, ..----

Furnaces out of shape, . - - - -

Fractured plates, ------

Burned plates, ..----

Blistered plates, ------

Cases of defective riveting, - - - - -

Defective heads, ------

Cases of leakage around tubes, . - - -

Cases of leakage at seams, . . - -

Water gauges defective, - - - - ■

Blow-outs defective, ------

Cases of deficiency of water, . - - -

Safety-valves overloaded, . - - - -

Safety-valves defective in construction,

Pressure gauges defective, - - - - -

Boilers without pressure gauges, - - - -

Total, - - 2,637 - - 519

The large number of broken and loose braces which we find every month is a pretty
sure indication that there is abundant room for improvement in workmanship on the
part of some boiler-makers. If a brace is properly made and attached to a boiler, there
is no more reason why it should ever break or get loose than there is for a plate in the
shell to become loose and fall into the furnace. But that they do break, and get so loose
that they might as well be broken, is very certain.

The ways in which braces fail are various, and depend upon the construction of the
brace itself, as much as anything else. One of the commonest faults to be met with, is a
deficiency in the size of the eye, where the brace is attached to angle or T irons. We
have actually seen braces an inch in diameter, with the eye part not over one-half an

193

324

111

147

139

191

445

278

178

139

148 THE LOCOMOTIVE. [Octobeh,

iuch square, and this merely bent so as to form a hook instead of being bent around and
welded as it should have been. As might be expected under the circumstances, the hook
was well straightened out, and the head of the boiler badly bulged.

One of the best forms of brace is made by welding a crow-foot to the end of the
brace which is attached to the tube sheet, and riveting the whole thing rigidly to shell
and head. If one could be sure that the weld were always sound, this would be a first class
brace for parts of a boiler that are exposed to the fire ; but unfortunately this is not the
case. All experiments that have been made show that the strength of a welded joint is
a very uncertain thing, and cannot be depended upon to be much more than one-half the
strength of the solid part of the bar.

A very common way of attaching braces is to rivet two angle irons to the tube sheet,
make the brace with a single eye, and fasten with a pin. The objection to this method
is that the angle irons cover too much of the plate, and the space between them forms a
lodging-place for sediment, which is apt to give trouble if it is used on surfaces exposed
to the fire. In addition to this, the claw-hammer strain on the heads of the rivets in the
angle irons is apt to loosen it so that the braces become slack.

The best method of connecting braces is to rivet T irons to the tube sheet and
attach the brace by a pin and double eye, taking care to make the double eye of such a
size that its strength shall be at least equal to the body of the bracp. The T irons
should be riveted radially to tube sheet, and the braces also arranged radially. In this
manner all oblique strains are avoided, as well also as all twisting of the brace to make
the attachment to the shell. For surfaces exposed to the direct action of the fire, how-
ever, the plain crow-foot brace is to be preferred.

The model brace for all parts of a boiler will not probably be designed until we can
obtain mild steel castings which can be depended upon every time. Then a simple
crow-foot with a double eye may be cast, and the body of the brace made simply of a flat
piece of iron with a hole drilled near the end, and fastened to the crow-foot with a
straight pin. This would seem to be the most simple and reliable form of brace that
could be desired.

An Eighty-Pound Hailstone. — Considerable excitement was caused in our city
last Tuesday evening by the announcement that a hailstone weighing eighty pounds
had fallen six miles west of Salina, near the railroad track. An inquiry into the matter
revealed the following facts : A party of railroad section men were at work Tuesday
iifternoon several miles west of the town, when the hailstorm came upon them. Mr.
Martin Ellwood, the foreman of the party, relates that near where they were at work
liailstones of the weight of four or five pounds were falling, and that returning towards
Salina the stones increased in size, until his party discovered a huge mass of ice weigh-
ing, as near as he could judge, in the neighborhood of eighty pounds. At this place
the party found the ground covered with hail as if a wintry storm had passed over the
land. Besides securing the mammoth chunk of ice, Mr. Ellwood secured a hailstone
something over a foot long, three or four inches in diameter, and shaped like a cigar.
Mr. W. J. Hagler, the North Santa F^ merchant, became the possessor of the larger
piece, and saved it from dissolving by placing it in sawdust at his store. Crowds of
people went to see it, and many were the theories concerning the mysterious visitor. At
evening its dimension were 29X16 x 2 inches. — Salina {Kansas) Jottrnal.

Liverpool ranks as the most important port in the world, with an annual tonnage
of 2,647,372; London stands second, with a tonnage of 2,330,688; Glasgow third, with
1,432.364; New York fourth, with a tonnage of 1,153,676. As a manufacturing city,
New York leads the world. — Knowledge.

1882.] THE LOCOMOTIVE. 149

tttmttttt

HARTFORD, OCTOBER, 1882.

Phosphorus in Iron and Steel.

The question is sometimes asked. How much phosphorus is allowable in iron from
which good boiler-plate can be made ? We were favored recently with a call from Col.
J. F. Black, Sup't of the Shelby Iron Works, Alabama, and inquired of him as to his
experience in the matter. He said, " Our product is all charcoal iron. In 100 analyses of
the ore from which our iron is made, the highest percentage of phosphorus was 0.4 of
one per cent. This iron has been used by the Ewald Manufacturing Company, of Nash-
ville, Tenn., and is reported to have made a superior quality of plate iron.

Phosphorus, even in small quantities, has a decided eftect upon the malleability and
strength of iron at ordinary temperatures, causing "cold shortness," or a tendency to
break short off when cold. While this is true at ordinary temperatures, when hammered
or rolled at high temperatures no such effect would be produced. Karsten thought that
iron was not materially affected when the phosphorus did not exceed 0.5 per cent., and
up to 0.3 per cent, it only hardened, but did not diminish the tenacity. When iron con-
tains 0.6 per cent, of phosphorus it will often bend at right angles but wall not stand
the breaking test. Its value decreases very rapidly with the increase of phosphorus,
and with more than 1 per cent, it is extraordinarily " cold-short."

The highest limit for phosphorus in iron for making steel, we are informed, is 0.1
per cent. In the process of puddling dephosphorization takes place, and a large per-
centage of the phosphorus is eliminated. In steel low in carbon 0.1 per cent, renders it
very brittle, and almost unfit for any use.

It will be seen from the foregoing that great care is necessary in manufacturing iron
and steel plates for boilers. It not unfrequently happens that an inferior plate will find
its way, by accident or otherwise, into a boiler manufacturer's order. Its inferiority
will manifest itself in flanging, punching, or some of the processes of boiler construction,
and such a plate should be rejected at once. The practice of " peening " up skin cracks
and deeper cracks, caused in flanging, is pernicious. Such cracks show that either the
material or the workmanship, or both, are inferior. A good piece of flange work will
show neither cracks, flaws, or hammer marks. The flanges of boiler-heads are, as a rule,
turned at too sharp an angle. They should not be turned on a radius of less than 2
inches ; 2^ inches would be better.

Manufacturers often purchase second-hand boilers because they are cheap. Now
this may be well enough if, upon examination, they are found to be in fair condition,
and are to be used only at low pressures for heating water, heating buildings, or some
such purpose. But it very often happens that when the boiler or boilers are secured
they are connected with the engine and used at ordinary boiler pressure, and if a
" drive" in business comes the owners immediately run the pressure up excessively, and
complain and fume if an inspector objects to such pressure. If parties engaged in any
manufacturing business which has prospect of growth need additional power, we advise
them to get new. boilers. Don't take any chances on second-hand boilers for power
because they are cheap. If you do they will very likely give out at a time when you

i50 THE LOCOMOTIVE. [Octobeij.

can least afford to stop. We speak from knowledge of many cases. See that your
boiler-room is fitted up with good boilers, sufficient in number for your work, and fur-
nished with all the attachments required for convenient handling and safety. It is false
economy to neglect this department of the establishment, for upon its efficiency depends
in a great measure the success of your enterprise. In your eagerness to see a handsome
product going out from the front of the mill, don't forget the rear end, where is the
power that sets all the machinery in motion. Second-hand boilers are good in their
place, but not to be used, as a rule, as though they were new, nor can tliey be safely rated
at the same pressures.

The Hartford Steam Boiler Inspection and Insurance Company has just completed
the setting of four boilers of its own design for the Otis Company of Ware, Mass. The
boilers were built by R. F. Hawkins & Co., of Springfield, Mass.

It has also recently set three boilers of an improved design of the Drop-flue type,
for The Colt Patent Fire Arms Company of this city. These boilers were built by
Peter Amerman of Hartford.

It has also set boilers for The Pratt & Whitney Company, of the Water-front Tubular
type, built by H. B. Beach & Son of this city.

Boilers have also been designed and set for Smith, Northam & Robinson of this city,
including plans for boiler-house and chimney ; and for the East Hampton Rubber Thread
Comjiany, including boiler-house and chimney ; also for the Otis Company's Mills at
Three Rivers, Mass.

The boilers in the new mill of The Clark Thread Company of Ncav Jersey were
built and set from plans furnished by this company through its New York branch, R. K-
McMurray its Chief Inspector.

Boilers built and set from the company's plans are extensively used throughout the
country.

A VISIT to the Fair of the New England Manufacturers' and Mechanics' Institute,
now being held in Boston, reveals a rich collection of the ti^asures of Art and Industry.
Every variety of the steam engine, and all machinery connected with the manufacture of
cotton and woolen fabrics are here, and most of them in actual operation. The exhibit
of electric lighting apparatus is exceptionally fine, the entire building being so lighted.
The most prominent systems are the Edison, the Weston, and the Thomson-Houston.
The lighting of the Art Galleries by the Edison system produces a most brilliant effect.
The display of minerals and woods by the southern railroads is very fine. Many mag-
nificent specimens of iron and copper ore, and coal are to be seen. No one, who has an
opportunity, should fail to spend a day or two at this fair.

Dr. Siemens' Address.

For the past few weeks the daily papers have been filled with the most nonsensical
stuff imaginable, the burden of which is : " the Steam Engine is doomed." The imme-
diate cause of this unusual commotion in the quasi scientific world was the inaugural
address of Dr. C. W. Siemens, the President of the British Association, at Southampton,
England, on the 23d day of August last. For the benefit of those of our readers who
have had no chance to obtain the entire address in printed form, we reproduce from
Engineering that portion of it which relates more particularly to the electric transmission
of power ; and gas vs. electric lighting. We may be grossly mistaken, but to us it seems

1882.] THE LOCOMOTIVE. 151

to be nothing but a verj- shrewdly-framed argument for the benefit of the gas companies.
That portion of the address which relates to the substitution of gas engines for steam
engines is very interesting reading, but unfortunately only one side of the question is
stated, and that but imperfectly. We have no space for extended comments, so we will
ciU attention to but one point. The learned Doctor says that the efficiency of any heat
engine depends upon the range of temperature through which it works. This is true.
But the range of temperature through which the steam or any other heat engine
works, is. in practice, limited by, and only by, the materials of which the engine is made,
therefore it is difficult to see how gas can have any advantage over steam. Admit, how
ever, for the sake of argument, that the efficiency of the gas engine is double that of the
steam engine ; that is, the steam engine converts into useful work one-eighth of the heat
due to the combustion of the coal in the boiler furnace ; while the eras engine converts
into useful work one-fourth of the heat due to the combustion of the gas used. Then
we must bear in mind that this gas is only to be obtained /row coal, and from th7'ee to
four pounds of coal are necessary to the production of one pound of gas. The argument
that the by-products of gas manufacture are worth more than the value of the coal used
has very little weight, for in the majority of places where steam is used they Avould be
worthless. Further comment seems unnecessary. "We would be willing to wager any
sum that a hundred years hence, instead of being supplanted by any other motor, the
steam engine will be only more firmly established in public favor than it is now.

The address is, however, very interesting, and we strongly advise every one to read
it carefully.

Electricity is the form of energy best suited for transmitting an eflFect from one
place to another; the electric cuiTcnt passes through certain substances — the metals —
with a velocity limited only by the retarding influence caused by electric charge of the
surrounding dielectric, but approaching probably under favorable conditions that of
radiant heat and light, or 300,000 kilometres per second ; it refuses, however, to pass
through oxidized substances, glass, gums, or through gases except when in a highly
rarefied condition. It is easy therefore to confine the electric current within bounds, and
to direct it through narrow channels of extraordinary length. The conducting wire of
an Atlantic cable is such a narrow channel; it consists of a copjjer wire, or strand of
wires, o mm. in diameter, by nearly 5,000 kilometres in length, confined electrically by a
coating of gutta-percha about 4 mm. in thickness. The electricity from a small galvanic
battery passing into this channel prefers the long journey to America in the good con-
ductor, and back through the earth, to the shorter journey across the 4mm. in thickness
of insulating material. ........

Regarding the transmission of power to a distance, the electric current has now
entered the lists in competition with compressed air, the hydraulic accumulator, and the
quick running rope as used at Schaflfhausen to utilize the power of the Rhine fall. The
transformation of electrical into magnetical energy can be accomplished with no further
loss than is due to such incidental causes as friction and the heating of wires ; these in a
properly designed dynamo-electric machine do not exceed 10 per cent., as shown by
Dr. John Hopkinson, and, judging from recent experiments of my own, a still nearer
approach to ultimate perfection is attainable. Adhering, however, to Dr. Hopkinson's
determination for safety's sake, and assuming the same percentage in reconverting the
current into mechanical efl"ect, a total loss of 19 per cent, results. To this loss must be
added that through electrical resistance in the connecting line wires, which depends
upon their length and conductivity, and that due to heating by friction of the working
parts of the machine. Taking these as being equal to the internal losses incurred in the

152 THE LOCOMOTIVE. [October,

double proce33 of conversion, there remains a useful effect of 100 — 38 = 6'2 per cent,
attainable at a distance, ■which agrees with the experimental results, although in actual
]iractice it would not be safe at present to expect more than 50 per cent, of ultimate
useful eft'ect, to allow for all mechanical losses.

In using compressed air or water for the transmission of power the loss cannot be
taken at less than 50 per cent., and as it depends upon fluid resistance it increases with
distance more rapidly than in the case of electricity. Taking the loss of effect in all
cases as 50 per cent., electric transmission presents the advantage that an insulated wire
does the work of a pipe capable of withstanding high internal pressure, which latter
must be more cosily to put down and to maintain. A second metallic conductor is
required, however, to complete the electrical circuit, as the conducting power of the
earth alone is found unreliable for passing quantity currents, owing to the effects of
polarization; but as this second conductor need not be insulated, water or gas pipes,
railway metals or fencing wire, may be called into requisition for the purjiose. The
small space occupied by the electro-motor, its high working speed, and the absence of
waste products, render it specially available for the general distribution of power to
cranes and light machinery of every description. A loss of effect of 50 per cent, does
not stand in the way of such applications, for it must be remembered that a powerful
central engine of best construction produces motive power with a consumption of two
pounds of coal per horse power per hour, whereas small engines distributed over a dis-
trict would consume not less than five; we thus see that there is an advantage in favor
of electric transmission as regards fuel, independently of the saving of labor and other
collateral benefits. .........

In the electric railway first constructed by Dr. Werner Siemens, at Berlin, in 1879,
electric energy was transmitted to the moving carriage or train of carriages through the
two rails upon which it moved, these being suflBciently insulated from each other by
being placed upon well-creosoted cross sleepers. At the Paris Electrical Exhibition the
current was conveyed through two separate conductors making sliding or rolling contact
with the carriage, whereas in the electric railway now in course of construction in the
north of Ireland (which when completed will have a length of twelve miles) a separate
conductor will be provided by the side of the railway, and the return circuit completed
through the rails themselves, which in that case need not be insulated; secondary bat-
teries will be used to store the surplus energy created in running down hill, to be restored
in ascending steep inclines, and for passing roadways where the separate insulated con-
ductor is not practicable. The electric railway possesses great advantages over horse or
steam power for towns, in tunnels, and in all cases where natural sources of energy, such
as waterfalls, are available; but it would not be reasonable to suppose that it will in its
present condition compete with steam propulsion upon ordinary railways. The trans-
mission of power by means of electrical conductors possesses the further advantage
over other means of transmission that, provided the resistance of the rails be not very
great, the power communicated to the locomotive reaches its maximum when the motion
is at its minimum — that is, in commencing to work, or when encountering an exceptional
resistance— whereas the utmost economy is produced in the normal condition of working
when the velocity of the power-absorbing nearly equals that of the current-producing
machine. ..........

Electric energy may also be employed for heating purposes, but in this case it would
obviously be impossible for it to compete in point of economy with the direct combus-
tion of fuel for the attainment of ordinary degrees of heat. Bunsen and St. Claire
De Ville have taught us, however, that combustion becomes extremely sluggish when a
temperature of 1,800 deg. C. has been reached, and for eftects at temperatures exceeding
that limit the electric furnace will probably find advantageous applications. Its specific

1882.] THE LOCOMOTIVE. 153

advantage consists in being apparently unlimited in the degree of heat attainable, thus
opening out a new field of investigation to the chemist and metallurgist. Tungsten has
been melted in such a furnace, and 8 pounds of platinum have been reduced from the
cold to the liquid condition in 20 minutes.

The principal argument in favor of the electric light is furnished by its immunity
from products of combustion which not only heat the lighted apartments, but substitute
carbonic acid and deleterious sulphur compounds for the oxygen upon which respiration
depends ; the electric light is white instead of yellow, and thus enables us to see pictures,
furniture, and flowers as by daylight ; it supports growing plants instead of poisoning
them, and by its means we can carry on photography and many other industries at night
as well as during the day. The objection frequently urged against the electric light,
that it depends upon the continuous motion of steam or gas engines, which are liable to
accidental stoppage, has been removed by the introduction into practical use of the
secondary battery ; this, although not embodying a new conception, has lately been
greatly improved in power and constancy by Plante, Faure, Volckmar, Sellon, and others,
and promises to accomplish for electricity what the gas-holder has done for the supply
of gas and the accumulator for hydraulic transmission of power.

It can no longer be a matter of reasonable doubt, therefore, that electric lighting
will take its place as a public illuminant, and that even though its cost should be found
greater than that of gas, it will be preferred for the lighting of drawing-rooms and
dining-rooms, theaters and concert-rooms, museums, churches, warehouses, show-rooms,
printing establishments and factories, and also the cabins and engine-rooms of passenger
steamers. In the cheaper and more powerful form of the arc light, it has proved itself
superior to any other illuminant for spreading artificial daylight over the large areas
of harbors, railway stations, and the sites of public works. When placed within a
holophote the electric lamp has already become a powerful auxiliary in effecting military
operations both by sea and land.

The electric light may be worked by natural sources of power, such as waterfalls,
the tidal wave, or the wind, and it is conceivable that these may be utilized at con-
siderable distances by means of metallic conductors. Some five years ago I called
attention to the vastness of those sources of energy, and the facility oflered by electrical
conduction in rendering them available for lighting and power supply.

• •••••••••a

Assuming the cost of electrical light to be practically the same as gas, the prefer-
ence for one or other will in each application be decided upon grounds of relative
convenience, but I venture to think that gas lighting will hold its own as the poor man's
friend.

Gas is an institution of the utmost value to the artisan ; it requires hardly any
attention, is supplied upon regular terms, and gives with what should be a cheerful
light a genial warmth, which often saves the lighting of a fire. The time is, moreover,
not far distant, I venture to think, when both rich and poor will largely resort to gas as
the most convenient, the cleanest, and the cheapest of heating agents, and when raw
coal will be seen only at the colliery, or the gas-works. In all cases where the town to
be supplied is within, say, thirty miles of the colliery, the gas works may with advan-
tage be planted at the mouth, or still better at the bottom of the pit, whereby all haul-
age of fuel would be avoided, and the gas in its ascent from the bottom of the colliery,
would acquire an onward pressure sufficient probably to impel it to its destination. The
possibility of transporting combustible gas through pipes for such a distance has been
proved at Pittsburg, where natural gas from the oil district is used in large quantities.

154 THE LOCOMOTIVE. [October,

The quasi monopoly so long enjoyed by gas companies has had the inevitable effect
of checking progress. The gas being supplied by meter, it has been seemingly to the
advantage of the companies to give merely the prescribed illuminating power, and to
discourage the invention of economical burners, in order that the consumption might
reach a maximum. The application of gas for heating purposes has not been encouraged,
and is still made difficult in consequence of the objectionable practice of reducing the
pressure in the mains during daytime to the lowest possible point consistent with pre-
vention of atmospheric indraught. The introduction of the electric light has convinced
gas managers and directors that such a policy is no longer tenable, but must give way
to one of technical progress ; new processes for cheapening the production and increas-
ing the purity and illuminating power of gas are being fully discussed before the Gas
Institute ; and approved burners, rivalling the electric light in brilliancy, greet our eyes
as we pass along the principal thoroughfares.

Regarding the importance of the gas supply as it exists at present, we find from a
Government return that the capital invested in gas works in England, other than those
of local authorities, amounts to £30,000,000; in these 4,281,048 tons of coal are con-
verted annually, producing 43,000 million cubic feet of gas, or about 2,800,000 tons of
coke ; whereas the total amount of coal annually converted in the United Kingdom may
be estimated at 9,000,000 tons, and the by-products therefrom at 500,000 tons of tar,
1,000,000 tons of ammonia liquor, and 4,000,000 tons of coke, according to the returns
kindly famished me by the managers of many of the gas works and corporations. To
these may be added, say. 120,000 tons of sulphur, which up to the present time is a
waste product.

Previous to the year 1856 — that is to say before Mr. W. H. Perkin had invented his
practical process, based chiefly upon the theoretical investigations of Hoflfman, regard-
ing the coal-tar bases and the chemical constitution of indigo — the value of coal-tar in
London was scarcely a halfpenny a gallon, and in country places gas-makers were glad to
give it away. L'p to that time the coal-tar industry had consisted chiefly in separating
the tar by distillation into naphtha, creosote, oils, and pitch. A few distillers, however,
made small quantities of benzine, which had been first shown — by Mansfield, in 1849 —
to exist in coal-tar naphtha mixed with toluene, cumene, e^. The discovery, in 1856, of
the mauve or aniline purple gave a great impetus to the coal-tar trade, inasmuch as it oe-
cessitated the separation of large quantities of benzine, or a mixture of benzine and
toluene, from the naphtha. The trade was further increased by the discovery of the
magenta or rosaniline dye, which required the same products for its preparation. In
the meantime, carbolic acid was gradually introduced into commerce, chiefly as a disin-
fectant, but also for the production of coloring matter.

The next most important development arose from the discovery by Grsebe and
Lieberman that alizarine, the coloring principle of the madder root, was allied to anthra-
cine, a hydro-carbon existing in coal-tar. The production of this coloring matter from
anthracene followed, and is now one of the most important operations connected with
tar distilling. The success of the alizarine made in this manner has been so great that
it has almost entirely superseded the use of madder, which is now cultivated to only a
comparatively small extent. The most important coloring matters recently introduced
are the azo-scarlets. They have called into use the coal-tar hydro-carbons, xylene and
cumene. Napthalene is also used in their preparation. These splendid dyes have
replaced cochineal in many of its applications, and have thus seriously interfered with
its use. The discovery of artificial indigo by Professor Baeyer is of great interest. For
the preparation of this coloring matter tuluene is required. At present artificial indigo
does not compete seriously with the natural product; but should it eventually be per-
pared in quantity from tuluene, a further stimulus will be given to the coal-tar trade.

1882.] THE LOCOMOTIVE. 155

The color industry utilizes even now practically all the benzine, a large proportion
of the solvent najihtha, all the anthracene, and a portion of the naphthaline resulting
from the distillation of coal-tar ; and the value of the coloring matter thus produced is
estimated by Mr, Perkins at £3,350.000.

The demand for ammonia may be taken as unlimited, on account of its high agri-
cultural value as a manure; and, considering the failing supply of guano, and the grow-
ing necessity for stimulating the fertility of our soil, an increased production of ammonia
may be regarded as a matter of national importance, for the supply of which we have to
look almost exclusively to our gas works. The present production of 1,000,000 tons of
liquor yields 95,000 tons of sulphate of ammonia ; which, taken at £20 10s. a ton, repre-
sents an annual value of £1,947,000.

The total annual value of the gas works' by-products may be estimated as follows :

Coloring matter.

£3,350,000

Sulphate of ammonia, ...... 1,947,000

Pitch (325,000 tons), ...... 365,000

Creosote (25,000,000 gallons), ..... 208,000

Crude carbolic acid (1,000,000), .... 100,000

Gas coke, 4,000,000 tons (after allowing 2,000,000 tons consumption

working the retorts) at 128., .... 2,400,000

Total, .... £8,370,000

Taking the coal used, 9,000,000 tons, at 12s., equal £5,400,000, it follows that the by-
products exceed in value the coal used by very nearly £3,000,000.

In using raw coal for heating purposes these valuable products are not only absolutely
lost to us, but in their stead we are favored with those semi-gaseous by-products in the
atmosphere too well known to the denizens of London and other large towns as smoke.
Professor Roberts has calculated that the soot in the pall hanging over London on a
winter's day amounts to fifty tons, and that the carbonic oxide, a poisonous compound,
resulting from the imperfect combustion of coal, may be taken as at least five times that
amount. Mr. Aitken has shown, moreover, in an interesting paper communicated to the
Royal Society of Edinburgh, last year, that the fine dust resulting from tlie imperfect
combustion of coal is mainly instrumental in the formation of fog ; each particle of
solid matter attracting to itself aqueous vapor; these globules of fog are rendered par-
ticularly tenacious and disagreeable by the presence of tar vapor, another result of im-
perfect combustion of raw fuel, which might be turned to much better account at the
dye-works. The hurtful influence of smoke upon public health, the great personal dis-
comfort to which it gives rise, and the vast expense it indirectly causes tlirough the
destruction of our monuments, pictures, furniture, and apparel, are now being recognized,
as evinced by the success of recent Smoke Abatement Exhibitions. The most efiiectual
remedy would result from a general recognition of the fact that wherever smoke is pro-
duced fuel is being consumed wastefully, and that all our calorific efi'ects, from the
largest down to the domestic fire, can be realized as completely and more economically,
without allowing any of the fuel employed to reach the atmosphere unburnt. The most
desirable result may be effected by the use of gas for all heating purposes with or with-
out the addition of coke or anthracite.

The cheapest form of gas is that obtained through the entire distillation of fuel in
such gas producers as are now largely used in working the furnaces of glass, iron, and
steel works; but gas of this description would not be available for the supply of towns,
owing to its bulk, about two-thirds of its volume being nitrogen. The use of water-gas,
resulting from the decomposition of steam in- passing through a hot chamber filled with

156 THE LOCOMOTIVE. [October,

coke, has been suggested, but this gas also is ol)iectionable, because it contains, besides
hydrogen, the poisonous and iudorous gas, carbonic oxide, the introduction of which
into dwelling-houses could not be effected without considerable danger, A more satis-
factory mode of supplying heat separately from illuminating gas would consist in con-
necting the retort at different periods of the distillation with two separate systems ot
mains for the delivery of the respective gases. Experiments made some years ago by
Mr. Ellison, of the Paris gas works, have shown that the gases rich in carbon, such as
olefiant and acetylene, are developed chiefly during an interval of time, beginning halt
an hour after the commencement and terminating at half the whole period of distilla-
tion, whilst during the remainder of the time, marsh gas and hydrogen are chiefly
developed, which, while possessing little illuminating power, are most advantageous for
heating purposes. By resorting to improved means of heating the retorts wdth gaseous
fuel, such as have been in use at the Paris gas works for a considerable number of years,
the length of time for effecting each distillation may be shortened from six hours, the
usual period in former j'ears, to four, or even three hours, as now practiced at Glasgow and
elsewhere. By this means a given number of retorts can be made to produce, in addi-
tion to the former quantity of illuminating gas of superior quality, a similar quantity
of heating gas, resulting in a diminished cost of production and an increased supply of
the valuable by-products previously referred to. The quantity of both ammonia and
heating gas may be further increased by the simple expedient of passing a streamlet of
steam through the heated retorts towards the end of each operation, whereby the am-
monia and hydro-carbon still occluded in the heated coke will be evolved, and the volume
of heating gas produced be augmented by the products of decomposition of the steam
itself. It has been shown that gas may be used advantageously for domestic purposes
with judicious management even under present conditions, and it is easy to conceive
that its consumption for heating would soon increase, perhaps tenfold, if supplied sep-
arately at say 1 shilling a thousand cubic feet. At this price gas would be not only the
cleanest and most convenient, but also the cheapest form of fuel, and the enormous
increase of consumption, the superior quality of the illuminating gas obtained by selec-
tion, and the proportionate increase of by-products, would amply compensate the gas
company or corporation for the comparatively low price pf the heating gas.

The greater efficiency of gas as a fuel results chiefly from the circumstance that a
pound of gas yields in combustion 22,000 heat units, or exactly double the heat pro-
duced in the combustion of a pound of ordinary coal. This extra heating power is due
partly to the freedom of the gas from earthy constituents, but chiefly to the heat im-
parted to it in effecting its distillation. Recent experiments with gas burners have
shown that in this direction also there is much room for improvement.

In the production of mechanical efiect from heat, gaseous fuel also presents most
striking advantages, as will appear from the following consideration. When we
have to deal with the question of converting mechanical into electrical effect, or vice
versa, by means of a dynamo-electrical machine, we have only to consider what are
the equivalent values of the two forms of energy, and what precautions are necessary to
avoid losses by the electrical resistance of conductors and by friction. The transforma-
tion of mechanical effect into heat involves no losses except those resulting from im-
perfect installation, and these may be so completely avoided that Dr. Joule was able by
this method to determine the equivalent values of the two forms of energy. But in
attempting the inverse operation of effecting the conversion of heat into mechanical
energy we find ourselves confronted by the second law of thermo-dynamics, which says
that whenever a given amount of heat is converted into mechanical effect, another but
variable amount descends from a higher to a lower potentatial, and is thus rendered
unavailable.

1882.] TPIE LOCOMOTIVE. 157

In the condensing steam engine this waste heat comprises that communicated to the
condensing water, wliilst the useful heat, or tliat converted into mechanical effect, de-
j)ends upon the diff'erences of temperature between the boiler and condenser. The
boiler pressure is limited, however, by considerations of safety and convenience of con-
struction and the range of working temperature rarely exceeds 120 deg. Cent., except
in the engines constructed by 3Ir. Perkins, in which a range of 160 deg. Cent., or an
expansive action commencing at 14 atmospheres, has been adopted with considerable
promise of success, as appears from an able report on this engine by Sir Frederick Bram-
well. To obtain more advantageous primary conditions we have to turn to the caloric

or gas engine, because in them the coefficient or efficiency expressed by , may be

greatly increased. This value would reach a maximum if the initial absolute tempera-
ture T could be raised to that of combustion, and t' reduced to atmospheric temperature,
and these maximum limits can be much more nearly approached in the gas engine
worked by a combustible mixture of air and hydro-carbons than in the steam engine.

Assuming, then, in an explosive gas engine a temperature of 1,500 deg. Cent, at a
pressure of four atmospheres, we should, in accordance with the second law of thermo-
dynamics, find a temperature after expansion to atmospheric pressure of 600 deg. Cent.,
and therefore a working range of 1,500 deg. — 600 deg. = 900 deg., and a theoretical

eflBciency of p^ — ^^ = about one-half, contrasting very favorably with that of a good

expansive condensing steam engine, in which the range is 150 — 30 = 120 degrees Cent.,

and the efficiency ^.„ ~,,.,, = ^.
^ lo0-|-274 7

A good expansive steam engine is therefore capable of yielding as mechanical work
two-eevenih parts of the heat communicated to the boiler, which does not include the
heat lost by imperfect combustion, and that carried away in the chimney. Adding to
these, the losses by friction and radiation in the engine, we find that the best steam
engine yet constructed does not yield in mechanical effect more than one-seventh part of
the heat energy residing in the fuel consumed. In the gas engine we have also to make
reductions from the theoretical efficiency, on account of the rather serious loss of heat
by absorption into the working cylinder, which has to be cooled artificially in order to
keep its temperature down to a point at which lubrication is possible; this, together with
frictional loss, cannot be taken at less than one-half, and reduces the factor of efficiency
of the engine to one-fourth.

It follows from these conditions that the gas or caloric engine combines the condi-
tions most favorable to the attainment of maximum results, and it may reasonably be
supposed that the difficulties still in the way of their application on a large scale will
gradually be removed. Before many years have elapsed we shall find in our factories
and on board our ships engines with a fuel consumption not exceeding 1 pound of coal
per efi'ective horse power per hour, in which the gas producer takes the place of the
somewhat complex and dangerous steam boiler. The advent of such an engine and of
the dynamo-machine must mark a new era of material progress at least equal to that
produced by the introduction of steam power in the early part of our century.

From 40,000 to 50,000 slate pencils are manufactured at the pencil mill daily, at
Castleton, Vt., and sent to New York, whence they go far and near through this and
other countries. Thirty persons are employed in the mill and quany, and are paid
promptly every month. Three from one family in the village are paid §80 a month for
labor. Four men with machines point 40,000 pencils a day. — Industrial Journal.

158 THE LOCOMOTIVE. [October,

A Simple Method of Keeping Correct Time.

It is not generally known that there is available to every one a most simple and
accurate method of regulating a clock or watch, when access to Standard Time at short
intervals is inconvenient or impossible. It consists simply in observing the time at which
any particular star sets, or passes the range of two fixed objects, on different nights. It
is necessary to have the correct clock time to start with ; after that, a clock may be kept
within a very few seconds of Standard Time for any number of years without any
difficulty.

The Sun cannot be used for this purpose for the reason that there are only two days
in a year when it is on the meridian of a place at noon ly clock time. It may be as much
as 14^ minutes fast, or 16^ minutes slow on different days; and besides, the determina-
tion of its altitude with any degree of accuracy, requires the use of special instruments,
and much skill in observation.

To determine the time by observation of a star, on the contrary, is a matter of great
ease, and no instruments are necessary. The mode of operation is a follows. Select two
fixed points for a range of observation. If a westerly window can be chosen which
faces any building anywhere more than 25 to 30 feet distant, we have as good a post of
observation as we can desire. Drive a nail, or stick a pin into the window jamb ; or, if
anything more substantial is wanted, fix a thin piece of metal, with a very small hole in
it to sight through, in any convenient place, so that you can observe the time any star
sets, or sinks below the roof of the adjacent building, or whatever may be chosen as the
more remote sight. Then choose some well-defined star, the brighter the better, and with
your timepiece set right, (to start with,) observe the time it passes the range of your
sights. The exact time, as well also, as the date of this observation should le recorded^
then to find out at any subsequent time, how much your watch has varied from correct time,
observe the same star, and recollect that it sets just 3 minutes and 55.90944 seconds earlier
on any given night than it did the preceding night. Thus if our first observation was taken
some night when the star set at 9 hours 15 minutes, and 23 seconds; and at our second
observation, taken just one week later, it set at 8 hours, 47 minutes, and 52 seconds, we
would know that our watch had kept correct time. If it had set at 8 hours, 45 minutes,
and 52 seconds, we would know that our watch or cloc^f had lost 2 minutes during the
week. And similarly for any other variation. If the time at which it had set had been
8 hours, 49 minutes, 52 seconds, we should see that our watch had gained 2 minutes, and
so on.

If the location of our sights admits of it, we should select a star 90°, as nearly as
possible, from the pole star, for its apparent motion will be greater than that of one near
the pole, and the liability of error will be diminished. If a suitable selection can be made,
the error need not be more than three or four seconds, and it will not be accumulative.

From the fact that any given star sets nearly four minutes earlier each night, it is
evident that it will after a while, begin to set during daylight. Before this occurs it will
be necessary to transfer the time to some other star, which sets later. Thus we see that
the later in the evening our first observation is taken, the longer the same star may be
used. To transfer the time, of course is very simple, you merely have to observe the star
you have been using, note the time, and also the error and rate of variation of your
watch ; then as late as convenient the same evening, select the new star, observe its time,
and from the data of the first observation, calculate the exact time of its setting, or pas-
sing the range of your sights. This is a very simple matter and requires no explanation.
Then use the new star as long as possible, and transfer to another, and so on.

To facilitate observation and calculation, the following table from Trautwine's
Pocket Book is inserted.

1882.]

THE LOCOMOTIVE.

159

Table Showing How Much Eaklier a Star Passes a Given Range on Each Sue

CEEDiNG Night.

Night.

Min.

Sec.

Night.

Hour.

Min.

Sec.

Night.

Hour.

Min.

Sec.

55.91 >

15.01

34.11

51.82

10.92

30.02

47.73

6.83

25.93

43.64

2.74

21.84

39.55

58'

58.65

17.75

35.46

54.56

13.66

31.37

50.47

9.57

27.28

46.38

28 ' 1

5.48

23.19

42.29

29 < 1

1.39

19.10

38.20

1
2

57.30
53.21

h. f. s.

Notes and Queries.

W. H. W. Jr., Westville, Conn., asks:

1st. In introducing a boiler compound into the feed-water in order to prevent it
forming scale, is there danger of the sediment passing off in the steam, and injuring the
valve seats and cylinder, or will it remain in solution until blown off?

2d. When feeding a boiler by an inspirator, with impure water, through a heater
which heats it to 212°, will it form a deposit in the pipes between heater and boiler,
which will, in time, fill them up ?

3d. If a boiler is covered with fire clay for a non-conductor of heat, will it injure
the iron ?

Ans. Ist. The sediment will remain in the boiler unless the boiler primes, in which
case some of it would be carmed over into the cylinder. Some kinds of compounds,
however, contain ingredients which are volatilized by heat, and pass off with the steam
and are capable of doing much damage to valves and cylinders.

2d. If the water contained much sulphate of lime the feed-pipe would fill up in
time.

3d. No, not unless moisture has access to it.

J. A. H., New York, inquires :

Why is the compound engine more economical in the use of steam than the single
engine ?

Ans. First, because a greater expansion can be obtained ; second, the cylinder con-
densation for any given ratio of expansion is reduced, in consequence of the expansion
being divided between the two or more cylinders, so that the variation of tem-
perature in the cylinders when expansion takes place, is less than in the single cylinder
engine.

G. H. B., Des Moines, Iowa, asks :

What is the highest duty that lias ever been attained by the steam engine, and what
was the nature of the work performed ?

Ans, The liighest duty we have any record of is : 1 H. P., with a consumption of
^^<?!> pounds coal per hour, the work, pumping water.

»f

160

THE LOCOMOTIVE,

[October.

Incorporated
1866.

Charter Per-
-, petual.

Issnes Policies of Insurance after a Carefnl Inspection of tlie Boilers.

COVERING ALL LOSS OR DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

ARISING FROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full information concerning the plan of the Company's operations can be obtained at flje

Or at any Agency.

J. M. ALLEN, Prest. W. B. FRAITKLIN, Vice-Prest. J. B. PIEECE, Sec'y.

Board of Directors.

J. M. ALLEN. President.

LUCIUS J. HENDEE, Prest. ^tna Fire Ins. Co.

FRANK W. CHENEY, Cheney Brothers Silk Manu

facturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Holyoke Water

Power Co
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Manufacturing Co.
THOMAS O. ENDERS, of The ^tna Life Ins. Co.
LEVERETT BRAINARD, of The Case, Lockwood &

Brainard Co.

Gen. WM. B. FRANKLIN, Vlce-Prest. Colt's Pat. Fire-

Arms Mfg. Co.
GEO. CROMPTON, Crompton Loom Works, Wor-

Hon. THOS. TALBOT, Ex-Governor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. PARRY, of Baldwin Locomotive Works,
Philadelphia.

Hon. HENRY C. ROBINSON, Attorney at Law. Hart-
ford.

GENERAL AGENTS. CHIEF INSPECTORS.

THEO. H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKIM,
W. S. CHAMBERLIN.
J. L. SMITH.
H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FREE.MAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILY,

R. K. McMURRAY,
WM. G. PIKE,
JOSEPH CRAGG,
WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN,
J. H. RANDALL,
A. C. GETCHELL,
J. S. WILSON,

New York Citt.

Philadelphia.

Baltimore.

Boston, Mass.

Providence, R. I.

Chicago, III.

St. Louis, Mo.

Hartford.

Bredgeport.

Cleveland.

Cincinnati.

OFFICES.

Office, 285 Broadwny.
430 Walnut St.
10 So. Holliday St.
" 10 Pemberton Sq.
15 WeyboBset St.
115 Munroe St.
" 404 Market St.
218 Main St.
328 Main St.
246 Superior St.
" 53 West Third St.

®fe

0t0ati0tte.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series— Vol. III. HARTFORD, CONN., NOVEMBER, 1882.

No. 11.

Upright Tubular Boilers.

In our articles on boiler construction in previous numbers of The Locomotive, we
have uniformly urged the necessity of so planning and constructing boilers that there
should be every reasonable opportunity for thorough inspection. In upright tubular
boilers it is impossible to make an internal examination with the same care and thor-
oughness that an inspection can be made of a boiler where internal access can be had.
Hence, for this reason, everything should be done that is possible to enable an inspector
to examine the interior through suitable hand holes. The trouble with boilers of this
type is usually with the furnace sheets, the lower tube sheet, and the tube ends. If
sediment collects in the water leg, and on the lower tube sheet, the furnace sheets and
lower tube ends will most certainly be burned. Boilers of this type are often con-
structed as shown in the following Figure,

Fig. 1.

It will be seen that there is no provision for cleaning the boiler, and the water leg
in time, particularly if water carrying impurities is used, is filled solidly full, and often
the sediment covers the lower tube sheet to a greater or less depth, enclosing the tubes.
These portions are exposed to the greatest heat, and being unprotected by water must
of necessity become over lieated and greatly weakened. Every boiler of this type

162

THE LOCOMOTIVE.

[November,

should have three or four hand-holes at the bottom of the water leg, and at least four
just above the lower tube sheet, as shown in the following figure.

,r5.

Fig. 2.
With these provisions the sediment can be easily and frequently removed, by use of
a bent iron cleaner constructed for the purpose. Another matter which should not be
overlooked is the proper stay-bolting of the water leg. Boilers of this type, particularly
those of smaller diameters, are very often constructed without any stay-bolts. The
builders will say that the inner furnace sheet is so short that it is supported sufficiently
by the flanging at the top and bottom. But suppose the sheet becomes overheated and
softened. What is to prevent its collapsing or fracturing ? Or suppose from some disar-
rangment of the safety valve it becomes inoperative, and an unusual pressure accumu-
lates in the boiler. What then ? Such contingencies are liable to arise, and every boiler
should be so constructed as to have ample margin for such contingencies. The following
figure shows the rupture of the furnace sheet of such a boiler, that had no staying.
The boiler was 30 inches in diameter, and the accident occurred from over pressure, the
safety valve having been overloaded.

1882.] THE LOCOMOTIVE. 163

In some cities where inspection laws are in operation, the rule applied for ascertain-
ing the resistance of cylindrical furnace sheets to collapsing is the same as that used
for cylindrical flues — Fairbairn's Rule — and boilers made for such markets could not be
approved without proper staying of the furnace sheets. Upright Tubular Boilers are
very generally used where small power is required. They will be found in our business
blocks, for job printing offices and small mechanical shops, therefore those who pur-
chase and use them should be sure that they are well and properly constructed.

Inspectors' Reports.

September, 1882.

The number of visits of inspection made during the month of September last, was
2,486. The total number of boilers examined was 4,798, of which 1,696 were complete
internal and external inspections. The number of boilers tested by hydrostatic pressure
was 438.

The number of defects found which were sufficiently serious to be reported was 3,127,
of which number 648, or 20.7 per cent., were considered dangerous. The number of boil-
ers condemned was 37.

The following is a statement of the defects in detail ;

Nature of defects.
Cases of deposit of sediment, ...

Cases of incrustation and scale, ...

Cases of internal grooving, - - - -

Cases of internal corrosion, - . - -

Cases of external corrosion, - - - -

Broken and loose braces and stays, - - -

Defective settings, - ... -

Furnaces out of shape, ....

Fractured plates, . . . - -

Burned plates, _ . . . .

Blistered plates, .....

Cases of defective riveting, . . - -

Defective heads, . . - . .

Cases of leakage around tubes, . _ -

Cases of leakage at seams, ...

Water gauges defective, . . - -

Blow-outs defective, . - . . -

Cases of deficiency of water, ...

Safety-valves overloaded, ....
Safety-valves defective in construction.
Pressure gauges defective, . - - -

Boilers without pressure gauges, ...

Total, - - 3,127 - - 648

One of the most important parts of a steam boiler is the blow-off. It is also one
that is subject to more abuse in its construction, location, and use tjian almost any other
fixture pertaining to the boiler. The most peculiar ideas seem to prevail in regard t(Jits
construction and position on the boiler. Some put it at the front end, some at the back
end, and some put it in the middle of the shell. The great majority also, instead of

Whole number.

Dangerous.

262

370

140

115

155

786

139

462

135

196

142

-[64 THE LOCOMOTIVE. [Novembek,

putting it on the bottom of the shell, where it belongs, insert it through the heads of
the boiler, anywhere from 2 to 6 inches above the bottom of the shell, thus reiulering it
impossible to entirely empty tlie boiler when desired, and greatly impairing its efficiency
for any purpose.

The only place for a blow-off pijje to enter a horizontal externally-fired boiler is
through the bottom of the shell within a foot or so of the back head. The boiler should
beset slightly lower at the back end than at tlie front, say three-fourths of an inch for
a boiler 15 feet long. Then it may be entirely emptied by simply opening the blow-off
valve, and all syphoning of water out through hand holes is obviated.

This however is not the most important reason for locating the blow-off at the back
end of the boiler. In a horizontal externally-fired boiler the application of the heat, and
the resulting circulation of the water, is such that the sediment is always deposited at the
back end to a much greater extent than in any other part of the boiler. Obviously,
then, this is the place for the blow-off. It is true that most boiler-makers now place it
there, but there are many who still persist in placing it at the front end.

The proper method of constructing and attaching the blow-off pipe to the ordinary
horizontal boiler is as follows: First, the pipe should be 2 inches in diameter. A circu-
lar piece of boiler plate about 8 inches in diameter should be riveted on the bottom of
the shell, with its center not over 12 inches from the back head. The hole for the pipe
had better not be made until after this piece is riveted on, and then it should be drilled.
If, however, facilities are not available for doing the job in this way, it may be drilled
before it is put on. The hole should then be tapped, when it is ready for the pipe. The
rivet holes on the inside of the shell should always be countersunk, and the heads of the
rivets driven flush with the inner surface of the plate. If this is done there are no pro-
jecting rivet heads to assist in the collection of sediment at this point. A blow-off
attached in this manner and provided with a straight away valve outside the setting
will always give perfect satisfaction if properly cared for. In many cases however, where
the water is bad, they are not opened often enough, and the inevitable consequence is
that they soon become filled uj) with scale and sediment. When this occurs it may
always be regarded as the best possible proof that it is located in just the right place,
and, if properly attended to, will prove most effective i^ keeping the boiler free from
scale and sediment.

Yesterday afternoon an employee of William Michaeles, a dentist at 82 East Fourth
street, put three sets of teeth into a vulcanizer to harden them. The vulcanizer is a
copper boiler 3| inches in diameter by 7 inches long. The process requires the teeth to
be placed in small flasks. The flasks are put in the boiler, and the boiler is filled with
water. The top of the boiler is screwed on, and a gas jet raises the temperature to 320
degrees. Before the right temperature was reached yesterday, the boy, while looking
through the laboratory door, saw the safety plug blow out, and then the boiler went
through the ceiling of the room. The windows were broken, and the furniture injured
to the extent of $50. One of the flasks was broken open by the explosion, and no trace
of the teeth has been found. — Sun, Nov. 10, 1882.

Tower City, Dakota, has a water supply from a remarkable artesian well. When
the earth was penetrated 569 feet salt water was obtained. Twenty feet further down a
gravelly stream was struck, which yielded salt water also. When a depth of 604 feet
had been reached, fresh Avater mixed with quicksand came up. At a depth of 675 feet
a flow of pure water was obtained, and the quantity is steadily increasing.

1882.] THE LOCOMOTIVE. 165

$t0

HAETFORD, NOVEMBER, 1882.

We have frequently warned manufacturers against using open heaters, especially
where the water was heated by exhaust steam from the engine. The oil contained in the
exhaust steam is very liable to make trouble, especially if the feed-water is impure, or
contains carbonate of lime or magnesia, or organic matter in any considerable quantity.
The oil or grease combines with these substances, and forms a conglomerate mass that is
sometimes especially troublesome. "We have not unfrequently found the fire sheets of
boilers greatly overheated from this cause, and their strength destroyed. A deposit
which would naturally fall down as a fine powder and be easily blown out, soon mixes
with the grease, forming a pasty substance which adheres to the plates, and when the
boilers are blown down it at once bakes on to the hot plates and is removed with no little
difficulty. "We have removed this deposit from boilers when the amount of organic matter
was large, and when dried it burned readily on being put into a gas flame. The amount
of oil daily used by engineers in the cylinder of an engine varies considerably. For in-
stance, in eighty H. P. engines we have known the quantity to vary from one-half pint
to more than a pint, and the larger quantity makes the most trouble. These difficulties
have been remedied by substituting coil or tubular heaters. Another trouble whicli occa-
sionally occurs in the use of condensed water is this. The drip or condensation from
cotton mill slashers and dressers is sometimes returned to the boiler. "We have found in
some cases that the boilers at once began to show internal corrosion. A recent case, —
two nearly new boilers had been running since placed in position with good results. The
condensed water from the slashers was subsequently fed to the boilers and signs of internal
corrosion began to appear.

The cause of this we attribute to the steam having been in contact with the copper
drying cylinders, large and small. This theory is not fully established in our minds, but
from the cases which we have seen, we believe corrosion has occurred from this cause.
The quality of water, however, may have had much to do with it.

Mr. Francis B. Allen, who has been connected with the New York Department of
the Hartford Steam Boiler Inspection and Insurance Company for the past eleven
years, has been transferred to the Home Office in Hartford, to act in the capacity of Su-
pervising General Agent. Mr. Allen is by profession a mechanical engineer, was an engi-
neer in the Navy during the war, which together with his experience with this company,
especially fit him for his new position.

Our enterprising contemporary, which has been so long and favorably known as the
Boston Journal of Commerce^ has changed its name to Cotton, Wool., and Iron^ which more
clearly indicates the character of its contents. Cotton, "Wool, and Iron are the three
great industrial staples, and, being their accredited representative, our contemporary has
fairly earned the right to its new title.

Tlie November number of the Manvfacturer and Builder has a timely article on fatal
accidents with electric light wires. It shows the difficulties and dangers of splicing
" live wires," giving an account of the manner in which it is done. Few persons not fa-
miliar with the electric light are aware of the dangers attending its care and successful
operation.

166

THE LOCOMOTIVE.

[November,

Unclassified Data.

BY J. n. COOPER.

" With good ■wrought-iron, the permanent set is so slight for loads below the limit
of ten to twelve tons per square inch, or about one-half the breaking weight, as not
to be sensibly felt in a boiler shell." — Wilson on Steam Boilers, p, 214.

" To allow for contingencies the elastic limit should not be taken at more than two-
lifths the breaking strength of the joints, which is the limit of test pressure to which a
new boiler should be strained. This may also be applied to an old boiler," — Wil-
son, p. 215.

" The working pressure of new boilers whose condition is known and regularly
ascertained at intervals of six to twelve months, a factor of safety of five or even less
may be used." — Wilson, p. 216.

"A boiler that has been at work for some time and has thus in a manner proved its
capability of bearing a given pressure may be considered safe if it will stand a test of
one and a half times its working load." — Wilson, p. 225.

D. K. Clarke. Rules, Tables, and Data for Mechanical Engineers. London, 1877.
Page 640 :

Conclusions on the Strength of Rivet Joints in Iron Plates; — " It may be
concluded that the tensile strength of iron plates of good quality is not materially im-
paired by punching, when done under proper conditions. Also, that the shearing section
of rivets should not in any case exceed the net section of plate ; and that the maximum
strength of joint is attainable when the shearing section is from ninety to one hundred
per cent, of the net section of plate. In the order of strength the joints proportioned
on this principle range thus :

Solid plate, --.._.. 100 per cent.

Double riveted lap joint, ----- 72 per cent.

Single riveted lap joint, ----- 60 per cent.

These percentages are to be accepted for plates not more than seven-sixteenths thick.
For boilers they give wider pitches than are usually practiced, but they are nevertheless
right." M

Mr. "W. S. Hall gives the following table* of proportions, which may be taken as a
guide, not as a hard and fast rule :

Proportions of Rivet Joints.

Double Riveted
Zigzag Joints.

Single Riveted
Joints.

Thickness of Plate, . - . .
Diameter of Rivet, ....
Breadth of Lap, -----
Pitch of Rivets in Line, - - - -
Distance apart of Pitch Lines,
Distance from Edge to Plates,

1.0
1.7

8.3
7.1

2.8

2,7

1.0
1,7
5,4
4,6

" Mr, Paul Havrez gives a table of proportions of single rivet joints, embracing
average good practice in France," from which we select a few examples :

Thickness of Plates. Diameter of Rivets. Pitch of Rivets. Lap of Joint.

.236 ,551 1,69 1.73

,276 .630 1.89 1.97

,315 .669 2.01 2.13

.354 ,748 2,13 2,20

* The above table is somewhat blind, but as we understand it the thickness of the plate is the basis of the
calculation. The results do not fully accord with recent American practice. — Ed. Locomotive.

1882.]

THE LOCOMOTIVE.

167

D. K. Clarke, Tables aud Rules, p. 625 :

" Wrought Iron. — For bars and plates, five tons per square inch of net section is
taken as the safe tensile stress; for bar iron of extra quality, six tons, and for steam
boilers the 'factor of safety' is taken at one-fourth to one-eighth." Mr. Roebling says:
"Long experience has proved beyond the shadow of a doubt that good iron, exposed to
tensile strain not above one-fifth of the ultimate strength, and not subject to strong vibra-
tion or torsion may be depended upon for a thousand years."*

Mr. Rankine gives the following data as factors of strength :

Dead Load. Live Load.

Perfect materials and work, ----- 2 4

Good ordinaiy materials and work, _ . - - 3 6

Dead loads are such as are put on quietly and remain.

Live loads are such as are put on suddenly, accompanied with vibration.

Humber, London 1870, p. 70, in his work on bridges, repeats the same factors n?,
above.

For the maximum working strength of the material of a boiler and the joints, the
proportion of one-fifth of the ultimate strength may safely be adopted. In selecting this
proportion we are fortified by the practice of wrought iron bridge engineers, who adjust
the lower metobers of such bridges to a working tensile strain of four to five tons per
square inch ; the metal so employed being of Staffordshire manufacture, supposed to
have an ultimate tensile strength of twenty tons per inch.

The ultimate and working tensile strengths taken atone fifth the ultimate are placed
together for reference in the following table :

Low Moor.

Staffordshire.

Descbiption.

Strength
percent.

Ultimate
Strength.

Working
Strength.

Strengtl\
per cent.

Ultimate
Strength.

M'orking
Strength.

Entire Plate,
Double Rivet Lap,
Single Rivet Lap,

100

72
60

56,000
40,320
33,600

11,200
8,064
6,720

100

72
60

44,800
32,480
26,880

8,960
6,496
5,376

For the strength of the joints of the best American plates, allow one-half more than
for best Staffordshire plates ; for ordinary American plates, one-tldrd more, and for cast
steel, douhle. The contents of the table are correct for three-eighth inch plates, and for
thinner plates.

In round numbers the working strengths of best boiler plates are as follows :

Yorkshire, per square inch of entire section, - - - 11,000 lbs.

Staffordshire, per square inch of entire section, - - - 9,000 lbs.

American, per square inch of entire section, - _ - 14,000 lbs.

American (ordinary), per square inch of entire section, - - 12,000 lbs.

Cast Steel Plates, per square inch of entire section, - - 18,000 lbs.

Mr. Clarke gives the working pressures in an extended table, from which Ave take
the following for a 54-inch boiler;

Thickness of Plates. Single Riveted. Double Riveted.

One-fourth inch, ..... 62 lbs. 74 lbs.

Five-sixteenths inch, ----- 77 lbs. 92 lbs.

Three-eighths inch, ----- 92 lbs. Ill lbs.

The bursting pressure is five times the working pressure.

♦ The reader will be careful to note that the conditions enumerated here do not apply to engines or boilere-
under ordinary conditions of practice.— Ed. Locomotive.

168

THE LOCOMOTIVE,

[NOVEMBEH,

Useful Notes on Lead, Copper, and Brass in Various Forms.

(Tables from Trautwine's Pocket Book.)
ROLLED LEAD, COPPER, AND BRASS IN SHEETS AND BARS.

S o ° es

LEAD.

COPPER.

BRASS.

*- '^ 5; u

0: -7, ^ CD

a, CO i: -■ W

Slieets

Sq. Bars

R'ndBars

Sheet?

Sq. Bars

R'd Bars

Sheets

Sq. Bars

R'd Bars

« S r. p -

per

per
Lii/al Ft.

per

2 2»^

pSogl

Sq. Foot.

Lin'al Ft.

Sq. Foot.

Liu'al Ft.

Liu'l Ft.

Sq. Foot.

Lin'al Ft.

^.^'o5

Inches.

Lbs.

Inches.

1
■55

1.86

.005

.004

1.44

.004

.003

1.36

.004

.003

3.73

.019

.015

2.89

.015

.012

2.71

.014

.011

1??

5.58

.044

.034

4.33

.034

.037

4.06

.033

.025

7.44

.078

.061

5.77

.060

.047

5.42

.050

.044

TtV

9.30

.121

.095

7.20

.094

.074

6.75

.088

.069

b'V

3
Iff

11.2.

.174

.137

8.66

.135

.106

8.13

.127

.100

-h

13.0

.237

.187

10.1

.184

.144

9.50

.173

.136

14.9

.310

.244

11.5

.240

.189

10.8

.336

.177

-x^d-

18.6

.485

.381

14.4

.376

.295

13.5

.353

.377

22.3

.698

.548

17.3

.541

.425

16.3

.508

• .399

26.0

.950

.746

20.2

.736

.578

19.0

.691

.543

L 0

29.8

1.24

.974

23.1

.963

.755

21.7

.903

.709

-I'o-

33.5

1.57

1.23

26.0

1.22

.955

24.3

1.14

.900

J. 0

37.2

1.94

1.52

28.9

1.50

1.18

27.1

1.41

1.11

40.9

2.34

1.84

3L7

1.82

1.43

29.8

1.70

1.34

1 1

44.6

2.79

2.19

34.6

3.16

1.70

32.5

3.03

1.60

48.3

3.27

2.57

37.5

2.55

1.99

35.2

3.38

1.87

1 3

52.1

3.80

2.98

40.4

2.94

2.31

37.9

2.76

2.17

if
1

56.0

4.37

3.42

43.3

3.38

2.65

40.6

3.18

2.49

59.5

4.96

3.90

46.2

3.85

3.03

43.3

3.61

2.84

66.9

6.27

4.92

52.0

4.87

3.82

48.7

4.57

3.60

74.4

7.75

6.09

57.7

6.01

4.72

54.2

5.64

4.43

81.8

9.37

7.37

63.5

7.28

5.72

59.6

6.82

5.37

89.3

11.2

8.77

69.3

8.65

6.80

65.0

8.12

6.38

96.7

13.1

10.3

75.1

10.2

7.98

70.4

9.53

7.49

104.

15.2

11.9

80.8

11.8

9.25

75.9

11.1

8.68

112.

17.5

13.7

86.6

13.5

10.6

/ 81.3

12.7

9.97

119.

19.8

15.6

92.3

15.4

12.1

86.7

14.4

11.3

In connection with the above table it will be found useful to memorize the following
points:

A piece of sheet lead one foot square and one inch thick weighs, in round numbers,
60 pounds, or just one-half more than a slieet of iron of the same dimensions, the iron
b*ing taken in round numbers at 40 pounds.

A similar piece of copper weighs, in round numbers, 46 pounds, and one of
brass, 43 poimds. For the requirements of approximate calculation, it will be near
enouo-h, in most cases, to call both copper and brass 45 pounds, which is easily remem-
bered from the fact of its being three- fourths of the weight of lead; or one-oiglith more
than that of iron.

The weiglit of a square bar of lead 1 inch square and one foot long is, in round
numbers, 5 pounds; and that of a round bar of the same metal, 1 inch diameter, and 1
foot long, 4 pounds, nearly.

Tlie weight of a square bar of either copper or brass, 1 inch square and 1 foot long,
may, without much error, be taken at 3f pounds; and around bar of the same materials
1 inch in diameter and 1 foot long, may be taken equal to 3 pounds.

The weight of round bars of any given length varies directly as the square of their
diameters and that of square bars as the square of their sides.

1882.]

THE LOCOMOTIVE.

169

WEIGHT OF LEAD PIPES PER LINEAL FOOT.

THICKNESS OF METAL IN INCHES.

Inside

diameter

of Pipe.

3
T

linch.

Inches.

Lbs.

.305

.724

1.28

1.95

2.74

3.65

4.53

5.84

8.52

11.7

15.3

19.5

.866

.845

1.47

2.20

3.05

4.02

4.96

6.38

9.14

12.4

16.2

20.5

.427

.967

1.65

2.44

3.35

4 38

5.89

6.82

9.76

18.2

17.0

21.5

.488

1.09

1.83

2.69

3.66

4.75

5.82

7.31

10.4

13.9

17.9

22.4

.548

1.21

2.01

2.93

3.96

5.11

6.24

7.79

11.0

14.6

18.7

23.4

.670

1.46

2.88

8.42

4.57

5.85

7.10

8.77

12.2

16.1

20.4

25.4

.791

1.70

2.74

3.90

5.18

6.58

7.96

9.75

13.4

17.6

22.1

27.3

.911

1.95

3 11

4.39

5.79

7.31

8.82

10.7

14.6

19.1

28.9

29.3

1.03

2.19

3.47

4.88

6.40

8.04

9.67

11.7

15.8

20.5

25.6

31.2

1.16

2.44

3.84

5.37

7.01

8.77

10 5

12.7

17.1

22.0

27.3

33.2

1.28

2.69

4.21

5.85

7.62

9.50

11.4

13.7

18.3

23.4

29.0

35.1

1.40

2.94

4.58

6.84

8.23

10.3

12.8

14.7

19.5

24.9

30.7

87.1

1.52

8.18

4.94

6.88

8.84

11.0

13.1

15.6

20.7

26.8

32.4

39.0

1.64

8.43

5.31

7.32

9.47

11.7

14.0

16.6

22.0

27.8

34.1

41.0

1.76

3.67

5.67

7.81

10.1

12.4

14.8

17.6

23.2

29.3

35.8

42.9

1.89

3.92

6.04

8.80

10.7

13.2

15.7

18.6

24.4

30.8

37.6

44.9

2.01

4.16

6.40

8.78

11.3

13.9

16.5

19.5

25.6

32.2

89.3

46.8

2.25

4.65

7.18

9.76

12.5

15.4

18.2

21.5

28.1

35.1

42.7

50.7

2.49

5.14

7.86

10.7

18.7

16.8

20.0

28.4

80.5

38.0

46.1

54.6

2.73

5.63

8.59

11.7

14.9

18.8

21.7

25.4

32.9

•41.0

49.5

58.5

2.98

6.12

9.32

12.7

! 16.1

19.7

23.4

27.3

35.4

43.9

52.9

62.4

3.22

6.61

10.1

13.7

17.4

21.2

25.1

29.3

37.8

46.8

56.4

66.4

3.46

7.10

10.8

14.6

18.6

22.7

26.8

81.3

40.3

49.7

59.8

70.8

3.71

7.59

11.5

15.6

19.8

24.1

28.5

33.2

42.7

52.7

68.2

74.2

3.95

8.08

12.2

16.6

21.0

25.6

30.2

35.2

45.2

55.6

66.6

78.1

WEIGHT OF LEAD, COPPER, BRASS, AND IRON BALLS.

Diameter

Oast

Cast

Ca!?t

Diameter

Cast

ol Ball.

Lead.

Copper.

Brass.

Iron.

ot Ball.

Lead.

Copper.

Brass.

Iron.

Inches.

Lbs.

Inches.

Lbs.

.0082

.0026

.0024

.0021

22.7

17.9

15.9

14.6

.026

.021

.019

.017

26.0

20.8

18.6

17.0

.088

.070

.063

.058

30.1

24.1

21.5

19.8

.209

.167

.148

.136

34.7

27.7

24.7

22.7

.408

.325

.290

.266

39.6

81.7

28.8

25.9

.705

.562

.501

.460

45.0

86.0

32.0

29.4

1.12

.898

.795

.731

57.2

45.8

40.8

87.4

1.67

1.38

1.19

1.07

71.5

57.2

50.9

46.8

2.38

1.90

1.69

1.55

88.0

70.3

62.6

57.5

8.25

2.60

2.32

2.18

106.

85.8

76.0

69.8

4.34

3.47

3.09

2.88

127.

102.

91.2

88.7

5.68

4.50

4.01

3.68

151.

121.

108.

99.4

7.15

5.72

5.10

4.68

178.

148.

127.

117.

8.94

7.14

6.36

5.85

208.

167.

148.

136.

11.0

8.79

7.83

7.19

lOi

241.

198.

172.

158.

13.4

10.7

9.50

8.78

277.

222.

198.

182.

16.

12.8

11.4

10.5

817.

253.

226.

207.

18.9

15.2

13.5

12.4

360.

288.

257.

236.

foil

ows :

Cast lead,

((

copper,

brass,

iron,

170 THE LOCOMOTIVE. [Novembek,

From the last table we observe that the weights of balls 1 inch in diameter are as

.209 pounds.

.167 "

.148 "

.186 "

The cubical contents, and therefore the weight of balls, varies directly as the cubes
of their diameters. Hence, it is only necessary to cube the diameter of a ball of any given
size, and multiply by the weight of a l)all of the same substance 1 inch in diameter to
obtain its weight. It will be found useful, therefore, to commit the weiglits of 1-inch
balls to memory.

Or to find the weight in round numbers :

For lead, cube the diam. and divide hy 5.
" cojiper, " " " 6.

" brass, " " " 6|.

" iron, " " " 7^.

Lead may be hardened by alloying it with various other metals. From ^ to 3f per
cent, of antimony will generally render lead so hard as to be unfit for many of its appli-
cations. Lead for bullets for smooth-bored guns should be hardened by the addition of
from one-fourth to one-fifth of its weight of antimony. Rifle bullets should be made of
very soft lead. Common type metal consists of 4 parts lead and 1 part antimony. Ste-
reotype metal, which is somewhat more fusible, contains 79 per cent, lead, 15 antimony,
and 8 bismuth. For fine impressions, tin is sometimes substituted for the bismuth. To
alloy lead with these metals it is only necessary to melt the lead first, then add the other
metals. An alloy of lead and bismuth is much stronger than lead alone, if the propor-
tion of bismuth is not greater than that of the lead. Three parts of lead and two of
bismuth has a tensile strength ten times as great as lead, and is an excellent alloy for
pipes and wire.

Lead may be softened by melting it in shallow vessels exposed to the air, when the
above metals, especially antimony, which are the cause of iis hardness, are converted into
oxides, and float on the surface of the lead in the form of a slag which may be skimmed
ofi". The process should be continued until the desired degree of purity and softness is
attained.

Lead for shot contains from 3 parts for small, to 8 parts for large shot, of arsenic;
which not only renders it harder, but has an important influence in determining the spheri-
cal form of the shot when it falls through the colander in the melted condition.

The World's Production of Iron.

The aggregate production of iron in the different countries of the world furnishes
some figures worthy of note. The British and American yield is known, while Germany
produced in 1881, whether inclusive or exclusive of the production of Luxembourg is
not stated, about 2,863,400 tons of 2,240 pounds. Luxembourg produced 289,212 tons,
and this quantity is given separately in the subjoined statement. France jn-oduced
1,866,438 tons; Belgium, 622,288 tons; Russia, 231,341 tons; Austro-Hungary, 448,685
tons (in 1880) ; and Sweden, 399,628 tons. A few other countries will produce small
quantities; thus Italy is said to have produced 76,000 tons in 1877, and Spain, 73,000 tons
in 1873 ; the yield in Turkey is estimated at 40,000 tons, that of Australia and Japan, at

1882.] THE LOCOMOTIVE. 17i

10,000 ertch ; that of Canada, Switzerland, and Mexico, at 7,500 each ; that of Norway,
at 3,975 tons, and other countries are supposed to have produced in all, about 10,000 tons.
Assuming that the yield in minor countries was the same in 1881 as it was reported
to be at the latest dates, the whole yield may be thus stated :

Great Britain, . . - - _

United States, . . . . .

Germany, .....

France, .....

Belgium. ......

Austro-Hungary, - - - - .

Sweden, ......

Luxembourg, .....

Russia, -..-..

Italy,

Spain, ._....

Turkey, . ^ - . - -

Japan, - - - - - " -

All other countries, . . . .

Total, -..--. 19,487,610

In effect, Great Britain produced nearly 43 per cent, of all the iron made in the
world ; the United States, 21.3 per cent. ; Germany, 14.9 per cent. ; France, 9.2 percent.;
and all other countries, 11.6 per cent. The four countries which produced 88.4 per cent,
of the world's supply of iron are the foremost in power, in wealth, in literature, and in
science, and the two English-speaking nations produce nearly two-thirds of the whole.
The United States consumed 29 per cent., and Great Britain, 23.4 per cent, of the whole.
The total amount consumed by two nations alone thus being 52.4 percent. — The Iron
Age.

1881

8,377,364

1881

4,144,254

1881

2,863,400

1881

1,866,438

1881

622,288

1880

448,685

1880

399,628

1881

289,212

1881

231,341

1876

76,000

1873

73,000

40,000

1877

10,000

46,000

Duly of the Steam Engine.

" To obtain the possible mechanical duty of the theoretically perfect steam engine,
we must know first the absolute heating value of pure coal (carbon). This factor has
been carefully calculated by several eminent experimenters, who have determined that if
the entire quantity of heat given out in the combustion of one pound of pure carbon
could be directly transmitted without loss to water, it would be sufficient to raise the
temperature of one pound of water 7,900° of the Centigrade scale. Having this element
at hand, it is now easy to calculate the possible duty of the perfect steam motor. We
need only determine the mechanical equivalent of the thermal value of a pound of pure
coal, to learn the possible duty of the steam engine. This is found by multiplying the
thermal equivalent of coal by the figures representing the mechanical equivalent of heat
—namely, 7,900+1,390 = 10,980,000. This result represents foot-pounds. To convert
these figures into horse-power, which is a more familiar expression, we divide them by
33,000; and we shall have as a result that one pound of pure coal burned in one minute
in the perfect boiler, and utilized without loss in the perfect engine, should yield us in

the form of work '' ' =332 horse-power during one minute; or if burned during

one hour, then one-sixtieth of 332, or 5J horse-power, per hour. This is what the theo-
retically perfect steam engine should yield. In actual practice the average steam engine
(using the term to indicate the entire mechanism) requires from three to four pounds of
coal to develop a horse-power ; and the best forms of engine, representing the most

172 THE LOCOMOTIVE. [November,

approved construction, require from two to two and one-half pounds of coal per horse-
power, showing that in reality we have as yet onlj- been able to realize about 15 to 20 per
cent, of the theoretical value of our fuel. The chief elements of loss are imperfect com-
bustion, imperfect utilization of heated gases, radiation and conduction of heat to sur-
rounding objects, and friction. By the use of steam of much higher pressures than is at
present the custom, and by the further development of the use of steam exijausively,
there is no doubt that our engineers will in time approach much more closely to what
theory shows to be possible, than they have thus far succeeded in doing."

The above, which we clip fiora an exchange, is being quite extensively copied by
other papers, some of which ought to know better than to let it pass without criticism.
The statement contains serious errors, which are surprising considering the sou:ce of the
article. At the same time it looks plausible enough to deceive the average reader, who
has only a superficial knowledge of the matter.

The very serious error we refer to is the statement that the steam engine theoretically
yields ~)^ horse-power with one pound of coal per hour. Theoretically it docs nothing
of the sort. Theoretically the efficiency of the steam engine depends upon the range
of temperature through Avbich the steam may be used. We know that the superior
limit of this temperature cannot much exceed oOO degrees, or our engine will be
ruined. Theoretically we also know that the inferior temperature cannot be less than
212 degrees in a non-condensing engine, nor less than about 100 degrees in a condensing
engine. Theoretically we also know that the latent heat of steam, which forms a large
percentage of the total heat cannot be utilized by expansion, and must necessarily be
nearly all wasted. If we make a few simple calculations, we shall find that theoretically
if we use steam of 120 pounds per square inch absolute pressure, in a non-condensing
engine so perfect that there is no loss by imperfect combustion, imperfect utilization of
heated gases, radiation and conduction of heat to surrounding objects, or friction, the
utmost i^ower that can be developed by one pound of coal per hour will be ^\ horse-
power, or 1 horse-power with l^'j pounds of coal; if our pressure is 80 pounds absolute,
the utmost would be 1 horse-power with 1| pounds of coal. With a condensing engine
the result would be somewhat better ; in the first example 1 horse-power would be devel-
oped by -fg of a pound of coal, not less. This is true tli^ory.

In connection with this subject the following from Prof Cotterill's Treatise on the
steam engine may not be out of place : "It appears that, with such temperatures as can
be made use of in practice, two-thirds of the whole heat expended is necessarily wasted,
and thus the low efficiency is in great measure accounted for. The statement is still not
unfrequently made that the actual expenditure of heat in steam engines is ten times the
theoretical expenditure; but in any legitimate sense of the word ' theoretical ', it would
be much nearer the truth to sav three instead of ten." H. F. S.

An interesting experiment on the transmission of power by electricity was made at
the Munich Electrical Exhibition recently. Two Gramme dynamos were used, one located
in Munich and the other at Meisbach, 35 miles distant. They were connected by an
ordinary galvanized iron telegraph wire 4^ millimetres or about one-sixth of an inch in
diameter, being, in fact, a telegraph line placed at the disposal of the experimenters by
the German Telegraph Administration. A second wire was used instead of the earth
for the return circuit. The total resistance of the wire was 950 ohms. Tlie resistance
of each dynamo was 470 ohms. The total resistance of the working circuit was there-
fore 1,890 ohms. When the generator at Meisbach was driven 2,200 revolutions per
minute, 1,500 revolutions per minute were obtained on the receiving dynamo at Munich.
The percentage of power utilized at this distance was therefore ^f So = o'^'^'i' CO per cent,
of that expended, and at the time of the experiment a heavy rain was falling, which
must have considerably impaired the insulation of the line.

1882.] THE LOCOMOTIVE.- 173

Weight of Men and Women,

WEIGHED AT THE TENTH CINCINNATI INDUSTRIAL EXPOSITION, OCTOBER, 1882.

It will be remembered that permission was given the Department of Scientific and
Educational Appliances to employ a clerk to record the weights of men and women
being weighed on scales in the exhibit of the Howe Scale Company. The sheets con-
taining the record have now been added up, and the committee reports as follows :

The object sought was a determination of the average weight of men and women, a
fact often required by civil and mechanical engineers. Haswell states that the average
weight of 20,000 men and women, weighed at Boston in 1864, was — men, 14H pounds;
women, 124^^. We have always thought these weights too low for Western people. The
number weighed at the Tenth Cincinnati Industrial Exposition was 22,155,

And the total weight 3,072.306 lbs.

Men weighed 7,467, weight 1,150,108 "

Women weighed ..... 14,688, " 1,922.198 "

Averaged weight of men, 154.02 lbs.

" '• women, 130.87 "

For men this is 12.53 lbs. higher than the Boston average, and for women 6.37 lbs.
higher.

Wo also determined with reasonable certainty the average weight of people from the
country, independently of the general average. This was rendered possible by the excur-
sions that were coming here at various times from this and the adjoining States, parts of
which were weighed.

FOR OHIO.

Average Aveight of 141 men was 157.38 lbs.

" " 179 women was ' 133.26 "

FOR SOUTHERN INDIANA AND ILLINOIS.

Average weight of 124 men was 158.52 lbs.

" " 193 women was • . . . . 133.55 "

FOR KENTUCKY.

Average weight of 114 men was 158.43 lbs.

" " 188 women was 133.76 "

'The mean of these averages is so much above the general average as to attract atten-
tion. For men it is 4.09 pounds higher, and for women 2.65 pounds. The very high
and approximate average of these from Southern Indiana and Illinois and from Ken-
tucky, recalls the Kentucky origin of the former.

We are under obligations to the proprietors of the scales for furnishing assistant
weighers, thus enabling the work to proceed continuously.

W. A. CoLLARD, Chairman.
Cincinnati, Nov. 1, 1882,

— Cincinnati Artisan.

A Paper in the Revue Scientifique on the railways of Europe, gives a number of
interesting data. In 1840, America had 2,800 miles in working; England, 1,275 miles;
France, 310 miles; Germany, 290 miles; Belgium, 200 miles; Austro-Hungary, 89 miles;
Russia, 10^ miles; and Holland, 11 miles. In 1860, the United States possessed nearly
as many miles of track as the whole of the European system, having 30,460 miles,
against a European total of 31,700 miles; England was a long way ahead of Germany
in the length of her system, and France was much behind. In 1870, these conditions
were altered. During the ten years the European systems had more than doubled their

174 THE LOCOMOTIVE. [November,

mileage, which then had a total of 64,700 miles, America having at the same time 52,-
450. England still retained the lead in Europe, and Germany and France followed her
at a considerable distance, Germany being very little in advance of France. In 1878,
Germany possessed a much longer system than England, having 19,260 miles against
17,100 in England. On December 31, 1878, Europe had C8,060 miles of track; the
United States, 81,050 ; India, 7,530 ; Canada, 7,890 ; and Algeria, 465 miles. The United
States had much the greatest mileage in proportion to the population, having 1 mile to
every 476 persons ; Canada came next with 1 mile to every 606 people. In Europe,
Sweden took the lead with 1 mile to every 1,538 inhabitants, while England had but 1
mile to every 1,876 inhabitants, or only about one-fourth as much track per inhabitant
as the United States. The number of locomotives running at that time over all the lines
referred to was 30,079, representing a power of 10,000,000 horses.

Art Castings in Iron.

A new departure of great interest has recently taken place in iron founding. This
is the reproduction of various art works in iron castings. Shields ornamented with
repousse work, helmets ornamented in relief, medallions, plaques, and Japanese bronze
trays have been used as patterns, and successfully coj^ied. ~

The work has been done in an iron foundry in Chelsea, Mass. The most delicate
patterns have been successfully followed. One large shield represents the siege of Troy,
and is a copy of Cellini's shield. The numerous small figures are brought out clearly,
and defined with precision. The shield is 22 in. by 28 in., and is colored to represent
bronze. This bronzing is produced by copper deposited by electricity. Another shield,
heart shaped, and 22 in. by 26 in., depicts the conflicts between Jupiter and the Titans.
This has the natural color of the iron. Two circular shields show Bacchus, and accom-
panied by a leopard. A copy of a bronze plaque with a head of Shakespeare, and a
reproduction of some repousse work after Teniers are also to be seen.

A helmet elaborately ornamented with intricate designs has been reproduced from
a casting made at the Ilsenburg foundries, in Prussia. Many fine castings have been
made there, but there has been no attempt at classical art in the designs employed.
Some antique swords with curious hilts accompany the helmet. Even more interest-
ing are the reproductions in iron of two medallions. There are two small panels in
iron, which have been " bufi'ed " until they look like steel. One bears an exquisite
flower, with its delicate grace preserved in the prosaic medium in which it finds expres-
sion. The other bears some leopards taken from antique bronzes.

A Japanese lacquer tray, with fine ornamentation, has also been reproduced in iron
only a sixteenth of an inch thick. A medallion, with a head of Apollo in alto relief, is
as striking as the foliage and flowers that have been executed in low relief. The bronze
castings resemble beaten work in copper.

There are no especial peculiarities about the production of these castings. Amer-
ican iron is used, the moulds are of fine sand, and the best workmen and the greatest
care are employed. The "facing" of the moulds is of dust from the beams of the
foundry. Impressions are secured in the sand of the shield or panel to be cast, and the
mould formed in the usual way. The casts are put under a rag-wheel, with emery to
prepare them for plating. The work has been treated in difierent ways, being polished
to show the color of the metal, bronzed, copper-plated, and oxodized, simply that vail-
ing effects might be studied. The experiments have proved that remarkable fineness
can be obtained successfully in work in iron, and the art castings will now be placed on
a commercial basis. — Van Nostrand's.

1882.] THE LOCOMOTIVE. 175

Escape Pipes for Safely-Valves.

To the Editor of The Locomotive :

I wish to call attention through the columns of your paper to the dangerous
practice which some men persist in, of piping safety-valves with pipes smaller in
diameter than the valve is.

This is not a new subject I am aware, but I think that it is not as well understood
by some steam-fitters as it should be.

I knew of a boiler which contained nine hundred feet of heating surface and twenty-
five feet of grate surface, with one safety-valve four inches in diameter, which would be
large enough, under ordinary circumstances, to relieve the boiler and prevent over-
pressure, but it had an escape-pipe attached which was scant three inches in diameter.
The casual observer would say that was not much smaller than it should be, but when
you consider that a four inch safety-valve has an area of 12.5664 square inches and that
a three inch pipe has a sectional area of 7.0686 square inches, the difi'erence is more
apparent.

This valve, under these conditions, would not allow the steam to escape as fast as
the boiler could generate it, but when the pipe was removed, the difficulty disappeared.
In another case, a pipe was used which was about one-third the capacity of the valve,
and in another the pipe was but one-quarter the size of the safety-valve, but still it was
expected, in each instance, that the valve would discharge the steam as fast as it was
necessary. If the law compels the steam-user to apply safety-valves to his boilers which
are of ample size, to prevent accidents from over-pressure, and the engineers know them
to be in good working order, of what use are they if they have escape-pipes attached
which are so much smaller than the valves?

If it is necessary to pipe them at all do not fail to use pipes that are as large as the
valve calls for.

W. H. Wake.man, Jr.

Westville, Conn.

Notes and Queries.

W. H. W., Jr., Westville, Conn., inquires : —

First. If an automatic engine can do a certain amount of work with 40 pounds
steam pressure, cutting off at one-half stroke, what will be the theoretical economy in
using steam at 80 pounds pressure, and cutting oif shorter accordingly ?

Ans. About 67 per cent., neglecting cleai-ance, and cylinder condensation.

Second. Is there any difference in point of economy whether there are three gauges
of water or only one in a steam boiler, provided that one gauge will cover the tube eight
inches deep ?

Ans. One gauge would have a slight advantage in economy.

Third. Is it possible for a boiler to become so filled with grease from the exhaust
steam, and sediment from impure feed water, as to cause it to prime bad enough to blow
a cylinder-liead off, provided tlie clearance in cylinder is very small ?

Ans. Yes.

AccoRDiNC} to the Coal Trade Journal the largest vein of coal in the world has
recently been discovered in what was the Ute Indian reservation in Colorado. It covers
1,600 acres of land; the coal is semi-bituminous, of jet black color, and almost entirely
free from sulphur. It will smelt iron without coking, having been used by miners in the
neighborhood for dressing their steel tools, and found superior to charcoal for that pur-
pose.

176

THE LOCOMOTIVE.

[November.

Incorporated
1866.

Charter Per-
petual.

Issnes Policies of lusnrauce after a Careful luspecliou of llie Boilers.

COVERING ALL LOSS OR DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY^

ARISING FROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.

Full information concerning the plan of the Company's operations can be obtained at the

ooTvrT^ A iKT^Y^"^ OFi^ioE, :Ea:.i^:E=LTFo:E=LXD, ooisrnsr.

Or at any Agency.

J. M. ALLEN, Prest. W. B. FRANKLIN, Vice-Prest. J. B. PIEUCE, Sec'y.

Boa^i'd of Dii'ectorss.

J. M. ALLEX. President.

LUCIUS J. HEXDEE, Prest. ^tna Fire Ins. Co.

FRANK W. CHENEY, Cheney Brothera Silk Manu-

facturintr Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Holyoke Water

Power Co
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Manufacturing Co.
THOMAS O. ENDERS. of The ^tna Life Ins. Co.
LEVEUETT BRAINARD, of The Case, Lockwood &

Braiuard Co.

Gen. WM. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire-
Arms Mfg. Co.

GEO. CROMPTON, Crompton Loom Works, Wor-
cester.

Hon. THOS. TALBOT. Ex-Governor of Mass.

NEWTON CASE, ot The Case, Lockwood & Brainard
Co.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS T. PARRY, of Baldwin Locomotive Works,
Philadelphia.

Hon. HENRY C. ROBINSON, Attorney at Law. Hart-
ford.

GENERAL AGENTS. CHIEF INSPECTORS

THEO.H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKIM,
W. S. CHAMBERLIN,
J. L. SMITH.
H. D. P. BIGELOW,

C. C. GARDINER,

D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILY,

R. K. McMURRAY,
WM. G. PIKE.
JOSEPH CRAGG.
WM. IT. FAIRBAIRN,
B. M. LORD.
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN.
J. H. RANDALL,
A. C. GETOHRLL,
J. S. WILSON,

New York City.
Philadelphia.
Baltimoi e.
Boston, Mass.
Providence, R. I.
Chicago. Ii l.
St. Louis, Mo.
Hartford.
Bridgeport.

Cl,EVEL.\Nn.
CiNCINNATr.

OFFICES.

OiBce, 2.'^.5 Broadway.
430 Walnut St.
" 10 So Ilolliday St.
" 10 Pemberton Sq.
15 Weybosset St.
" 115 ^Iniiroe St.
" 404 Market St.
" 21S Main St.
" .3-28 Main St.
" 246 Superior St.
" 53 West Third St.

Stfe

0C0ni0tm.

PUBLISHED BY THE HARTFORD STEAM BOILER INSPECTION AND INSURANCE COMPANY.

New Series— Vol. III. HARTFORD, CONK, DECEMBER, 1883.

No. 12.

Upright Tubular Boilers.

In the November issue of the Locomotive, the ordinary Upright Tubular Boiler was
described and illustrated. We called attention to defects in construction, as the boiler is
usually made, viz., no provision for removing the sediment which collects in the water-
legs, and on the lower tube or crown-sheet, also the neglect of proper staying of the
sheets surrounding the furnace. There is another difficulty to which this type of boiler
is liable. The upper ends of the tubes being unprotected by water get overheated, and
the expansion resulting, together with the contraction from variations in temperature,
augmented, by cold feed-water (lieaters being rarely used with this type of boiler), cause
leaks around the tubes in the upper tube-sheet, making it necessary to expand or repair
the tubes frequently. To obviate this latter difficulty, the type of boiler illustrated
below is recommended.

S7E4M N(IZ2l£

HALT PLAN THROUGMA.B.

, It will be seen that the upper tube-sheet is independent from the shell, but con-
nected with a smoke-flue or uptake, which is largely below the upper head, and within
the boiler. The water-line in this boiler can be maintained a little above the upper

178

THE LOCOMOTIVE.

[December,

tube-sheet, thus entirely submerging the tubes, and removing the liability to overheat-
ing them at this point. By properly proportioning the parts, there w ill be no lack of
steam-room. This boiler has given entire satisfaction where used, is economical for
boilers of the upright type, and economical in repairs. We will add that the smoke-
flue or uptake should be stayed to the shell of the boiler as shown in the illustration.

Inspectors' Reports.

October, 1882.

There were made during the month of October last 2,333 visits of inspection, by
which 5,044 boilers were examined. Of this number 1890 were thoroughly inspected,
both internally and externally. The number of defects found foots up 3,718, of which
612 were considered dangerous. 453 boilers were tested by hydrostatic pressure, and
36 were condemned as unfit for further service.

The detailed statement of defects is as follows :

Nature of defects.
Cases of deposit of sediment,
Cases of incrustation and scale,
Cases of internal grooving, -
Cases of internal corrosion, -
Cases of external corrosion, -
Broken and loose braces and stays, -
Defective settings, - - -

Furnaces out of shape,
Fractured plates, . . _

Burned plates, _ - .

Blistered plates, . . _

"Cases of defective riveting, -
Defective heads, . - -

■Cases of leakage around tubes,
Cases of leakage at seams.
Water gauges defective,
Blow-outs defective, - - -

Cases of deficiency of water,
Safety-valves overloaded.
Safety-valves defective in construction.
Pressure gauges defective.
Boilers without pressure gauges.

Whole number. Dangerous.

293

469

222

124

102

113

118

294

754

402

- 151

278

9 -

175

Total,

3,718

612

Leakage at the girth seams, and around the tubes of externally-fired horizontal
tubular boilers, is one of the defects most often found, and one which is sure to become
very serious in a short time if not attended to, for it induces corrosion in one of its most
dangerous forms. There is nowhere to be found a better illustration of the truth of the
old saying, " a stitch in time saves nine," than in this matter; and also no better illustra-
tion of the economy and value of proper care and management for steam boilers.

Leakage at the seams of boilers may be induced by a variety of causes, of which we
need mention here only two, — bad workmanshij) and bad management.

When the defect is due to bad workmanship, the only helj) for it is, generally, to
dress and recaulk theedges of the plates. Sometimes, though not often, it will be neces-

1882.] THE LOCOMOTIVE. 179

sary to cut out the old rivets, insert new ones, and then dress and recaulk. This also is
generally necessary when a boiler has been overheated, through shortness of water, or
otherwise. Sometimes too much lap is given the plate, when it becomes impossible to
properly caulk the seams. The writer has in mind now a certain rotary bleacher, w hereon
the plates lapped /o?/?- inches beyond the rivets. The result may be imagined. Obviously
the only remedy in such a case is to reduce the lap.

Leakage is often induced by feeding cold water into a boiler, and delivering it close
to the hot plates over the fire. Severe local contraction is thus caused, which no mate-
rial can resist, and leakage is sure to follow. The solid plates of tlie shell are very fre-
quently fractured in tJiis manner. Where the use of cold water is unavoidable, the
boiler should always be provided with a circulating feed pipe, as a means of economy
and safety.

In too many cases, however, the seams are shaken by the habit, which prevails ex-
tensively, of pulling the furnace doors wude open, without closing the chimney damper.
This is a very common way of checking the generation of steam, when there is a lull in
the demand for it from any cause, and cannot be too strongly condemned. The efJect of
a large body of air some hundreds of degrees colder than the furnace and boiler, rush-
ing along the under side of the shell, is sutiicient to loosen the best joint that ever was
made, and in many cases it has fractured the shell through the solid plate. The effect
of this is even more marked with some tyjies of internally-lired boilers, such as the " drojj
flue," for instance, than it is with the common return tubular boiler.

Anotherfruitful source of damage to boilers, and one which has ruined thousands,
is the practice of blowing a boiler off and immediately refilling it with cold water, while
the brickwork is red hot. Nothing will tear a boiler to pieces quicker than this. Boil-
ers have exploded with disastrous effect from this cause, hours after the fire had been
drawn. Probably most persons, not familiar with the matter, would be surprised to
know the pertinacity with which cold water will cling to the lowest point of a boiler
under these circumstances. Local contraction of such severity is thus induced, that
nothing can withstand its effects, and a few rejjetitions arc generally sufficient to ruin
any boiler.

Enameling Cast-Iron Watek-Pu'es. — Two inventors in Bohemia are said to have
patented a process for enameling cast-iron water-pipes, which can be applied to other
hollow castings that are made with cores. It consists in simply covering the sand core
■with enamel, and then pouring in the iron as usual. The heat of the melted iron fuses
the enamel, which attaches itself tirmly to the iron, and detaches itself so completely from
the sand that the enamel is said to be all that can be desired for water-pipes and other
industrial purposes. In casting sinks, basins, urinals, etc., the enamel can be applied to
the sand on that side of the mold which is to form the inside of the basin. The compo-
sition of the new enamel is kept a secret, but it is said to differ from the old form in the
simplicity of its preparation and the extraordinary cheapness of the materials used. In
color this new enamel is gray. It will be useful for gas-pipes and soil-pipes, as well as
water-pipes, because it will make the pipes absolutely tight by a glassy lining. — The
Ironmonger.

A KAiLWAY carriage 'painted ins;de with the Balmain pho.sphorescent paint is in-
cluded in one of the trains between London and Rotlicrliithe, via the Thames tunnel.
Although only one-half of the available space of the carriage is painted, the phosphores-
cent light is quite sufficient to enable the passengers to distinguish small objects when
passing through the tunnel ; and, moreover, the light is powerful enough to enable a per-
son to read the indication of an ordinaiy watch. It is probable that the railway com-
panies will be enabled to effect a considerable saving in gas and oil by using the phos-
phorescent paint. — Boaton Advertiser.

180 THE LOCOMOTIVE. [DECExreER,

HARTFORD, DECEMBER, 1882.

"With tliis issue Vol. Ill of the New Series of The Locomotive closes. It has been
our endeavor to furnish our readers with facts and information that will be valuable
not only for present use, but for reference. We have avoided the introduction of fruit-
less discussions into our columns. Where a great variety of opinions or theories are ex-
pressed, the seeker after information wliich his needs require, is confused and discouraged.
One writer of acknowledged, reputation says one thing, while another of recognized abili-
ty takes him to task, and aims to refute his statements, and recommends something
entirely different. Which is right? Are the controversialists practical men ? What the
manufacturer wants is reliable information ; something he can put in practical use in his
own mill. Our aim has been to furnish such information to our readers on the subjects
treated in our columns. When we know, from repeated trials, that this or that practice
gives good results we are ready to recommend and advise their adoption. We would
not undervalue the benefits of discussion, for through discussion light is obtained, but
discussion without some good practical result is valueless. It may be racy reading, but
if nothing is proved it is fruitless.

We do not claim infallibility on the question of boiler construction, setting and man-
agement. But we do claim that the care of 17,000 boilers scattered over the country, of
almost all known types, under all conditions of use, with all kinds of fuel and qualities
of water, gives us opportunities of studying their comparative merits or demerits, econo-
my, efficiency, and adaptability which are aflbrded to few if any engaged in other occu-
pations. It is our purpose to continue the discussions bearing upon boiler construction,
boiler settings, and boiler explosions — the cause and prevention of the latter. The rec-
ords of inspection will be kept up, and our readers will be furnished with a summary of
these reports, with comments thereon, that cannot but be useful to all who have to do
with boilers. The question of economy in all manufacturing establishments is becoming
such a vital one that great attention is being given to the consumption of fuel. But in
the desire to provide an economical boiler do not place too much reliance upon the pub-
lished reports of comparative tests. It should be understood that such tests are made
under the most favorable conditions, such conditions as are rarely if ever found in actual
use. These tests may give some indication of comparative efficiency, but should not be
accepted as to the efficiency of the boiler in actual use in the mill. Much might be said
on this point, but we leave it to some future issue.

The Locomotive has now reached a monthly circulation of over (10,000) ten thou-
sand. It is much sought by engineers and manufacturers, and it will be our aim to make
it in the future even more valuable and interesting if possible than in the past.

Knowledge says : Some speculative merchants in Bergen have obtained the right of
cutting block ice for export from the enormous glacier Fon or Svartisen (60° 25' north,
35° 15' east), on the Senjen Island in Norway, the northernmost of its kind in Europe.
The quality of the ice is good. The glacier is about 120 square miles in extent, and the
distance from the border of the sea only two miles. A similar attempt t© utilize the
glacier Folgefonden was made some years ago, but failed, owing to the blocks in their
downward course breaking through the wooden conductor in which they were slid down
to the sea.

1882.] THE LOCOMOTIVE. 181

The articles entitled Unclassified Data^ which are being published in the Locomotive,
were handed to us by J. H. Cooper, who is well known to our readers. They are notes
jotted down by Mr. Cooper in his researches and readings running over a period of many
years, and are convenient for reference when the authorities quoted are not at hand. One
noticeable feature is the wide divergence of opinion on some points among men who are
eminent in the profession of mechanical engineering. It shows that the requisite data
for exact truth has not yet been found, and they probably never will be found until
iron or material of known and uniform quality can be produced the world over. We
would say further, and not until workmanship is uniformly first-class in every particular.
"We do not publish these data as our own views, and from many of them we dissent.
They are not in accord with the best American practice.

The Nautical Gazette (English) says that during the year 1881 the vessels lost at sea
averaged about one every twenty-four hours. A large proportion of these losses occurred
from carelessness, and mostly from fogs and other darkness. There were 400 ocean-
steamer collisions in 1879 and 1880 in the North Atlantic alone. Each of these might
have been avoided if the master of one colliding vessel had been informed in proper
time of the course pursued by the approaching one. These accidents give an average of
over one steamer a day in which human life was sacrificed and valuable property de-
stroyed. The Gazette believes that if a system of Fog Signals had been in use, such as
the Barker Code, nearly all of these disasters would have been avoided.

A FROG was recently found in the middle of a 250-pound cake of ice at New
London, Conn. After lying in a pail of water for a few moments, it showed signs of
life, and was soon very lively. The ice in which the frog was imprisoned was cut in
February, so that he must have been frozen some seven or eight months. ''

Prof. C. W. C. Fuchs announces that the total number of recorded earthquakes for
1881 is 297; volcanic eruptions, 10, the most important being that of Mauna Loa in
Hawaii.

The Transit of Venus.

The following article is from the Hartford Times of December 5th, and is so clear an
explanation of the Transit of Venus and its importance, that we are pleased to give it to
our readers. It was written by Prof. .John Brocklesby of Trinity College.

What is meant by the transit of Venus ?

When the planet Venus, in her motion around the sun, comes between the earth and
the sun, her passage across the face of the sun is called a transit.

As Venus shines only by the light which she receives from the sun, the side which
she then presents to the earth is in shadow ; and during a transit, she appears as a
black spot moving across the sun.

Why are observations on the transit of Venus deemed of such importance by
astronomers ?

Because by means of these observations a certain measurement can be obtained,
which enables them to determine the distance of the sun from the earth. This measure-
ment is the angle contained between- two imaginary lines, one drawn from the sun to

182

THE LOCOMOTIVE.

[December,

the center of the eartli, and another drawn from the same point on the smi to the earth,
touching its surface; or what is the same tiling, the apjiarent angular breadth of half
the earth's diameter (radius) as seen from the sun.

How is this angle found ?

Before answering this inquiry it is necessary to form an idea of what an angle is,
and how angles are measured. An angle is the opening between two straight lines that
meet at the aime point ; and the following explanation will serve to show how they are
measured. If we take the wheel of a bicycle, the opening between any two spokes
meeting at the center is aji angle, and it is measured by the space on the rim between the
spokes. If there were 3G0 spokes, at equal distances apart, the angle between any spoke
and the next is called a degree.

If this angle is divided into 60 equal parts it is termed a minute ; and the 60th part
of this is a second.

If a human hair were placed about fifty feet from a person, two lines drawn
from the opposite sides of the hair to tlie same point in the eye of the observer would
make an angle of one second — and the breadth of the hair is a measure of the angle, at
the distance mentioned.

The angle sought by the astronomers is found in the following way : In the figure
here shown let E, V, and S, represent the relative positions of the Earth, Venus, and tlie
Sun, when a transit occurs; H, V, I, a portion of the orbit of Venus; and FGa
diameter of the earth, perpendicular to the plane of the earth's orbit.

If at the time of the transit one observer is placed at F, and another at G, the ob-
server at F will see Venus in the direction of F V, appearing as a dark spot on the
sun at y, and, at the same time, the observer at G will see the planet in the direction of
G V on the sun at e. If the observers watch the planet during the whole time of the
transit, the path of the planet to the observer at F will be the line running through/,
and to the one at G the parallel line running through e.

Now the first thing to be detei-mined from these observations is the relative values of
the lines F G and ef.

It was discovered by Kepler that there is such a relation between the distances
of the planets from the sun, and their times of revolution about it, that when the latter
are known, the relative distances can be computed, and vice versa. The times of revo-
lution have been observed with the greatest exactness — within a fraction of a millionth
part of the whole period.

It is ascertained that, when a transit occurs, the distance of Venus from the sun is
2.6 greater than her distance from the earth ; that is, the line V e is 2.6 greater than V
G. And from the geometrical relations of the triangle F V G and e Y f, it follows that
the line ef is 2.6 greater than F G ; and as the number of miles in F G (the earth's
diameter) is known, the value of e / can be computed, and is found to be about 20,600
miles.

1882.] THE LOCOMOTIVE. 183

The next step is to find the angular value of the line e/, as seen from the earth.
The time that Venus occupies in making her circuit about the sun is accurately known,
and, in consequence, the time she takes to describe any small angular motion, as a minute
or a second, is also known. We have the same knowledge, likewise, in respect to the
sun's observed motion.

Having this knowledge, the observer at F, noting very exactly the timeit takes for
Venus to pass across the Sun through the line at/, thereby knows the number of angular
seconds she has described in that part of her orbit represented by the line through/.

The observer at G ascertains in the same way the number of angular seconds on the
parallel line that passes through e. The angular diameter of the Sun can be measured
by instruments, and from these three known quantities, we can, by a simple geometrical
calculation, find the number of seconds in the line e f.

We have already found the number of miles in the line e /, and dividing this num-
ber by the number of seconds in e /, we find that the linear value of one second at the
sun is about 462 miles — that is, if, at the distance of 50 feet from the observer, two lines,
which form an angle of one second, are separated only by the breadth of a human hair,
if extended to the sun, would be 462 miles apart.

The same would also be true if the observer was on the son and the lines extended
to the earth. An angle therefore of one second at the sun, covers on the earth a space
of 462 miles, consequently the radius of the earth (3,963 miles nearly) divided by 462
will give the approximate angle formed by two lines drawn from the same point on the
sun to the earth ; one touching its surface and the other extending to its center. This
angle from the latest computations varies but little from eight seconds and eight-tenths
of a second (8.8). It is called the solar parallax.

Now if we suppose a line drawn from the point where the first line touches the earth
to its center, a right-angled triangle is formed, and we now know enough of the value of
a sufficient number of its parts (viz., angles and sides) to compute the length of the line
drawn from the earth's center to the sun — the solar distance. This could not have
been computed from the triangle unless the parallax had been first obtained. The dis-
tance of the earth from the sun, as at present known, is somewhere between 92,570,000
and 93,000,000.

In this explanation we have supposed for convenience that the observers w^ere sta-
tioned at the poles of the earth, a little less than 8,000 miles apart ; but those stations
are not necessary in order to obtain the angle sought ; all that is required is, that the
stations should be as far apart as possible, so as to obtain a wide interval between the
paths at e and /.

In the last transit of Venus, in 1874, among other stations, one was in Siberia and
another in New Zealand. Among those selected for December 6th of this year, one has
been chosen by the Brazilian government at the Straits of Magellan, another at Per-
nambuco, and a third at Rio Janeiro. England has sent an expedition, among others, to
Cape Colony and Bermuda, and in the northern latitudes. Hartford is the station
selected by the German government. France also joins in the observations, and our own
astronomers have four northern and two southern stations. Washington, D. C, is one of
them and Santa Cruz in Patagonia another. May the skies be propitious. J. b.

Unclassified Data.

BY J. H. COOPER.

" By the limit of elasticity is generally meant, as is well-known, the least load by
which a permanent alteration of form is eff'ected." — Styffe^ p. 27, London, 1869.

* * * At higher temperatures, between 212° and 392°, the absolute strength of iron

184

THE LOCOMOTIVE.

[December,

is considerably greater than at ordinary temperatures, as Fairbairn found in his experi-
ments. See " Useful Information for Engineers, 2d Series, p. 288." No change in tensile
strength of wrought iron from zero to 400° Fah.

'' Between zero and 550 Fah. the engineer need make no provision for effect of differ-
ence of temperature." — Barr on Steam Boilers, p. 147.

"As riveted joints destroy the elastic homogeneousness of the boiler, the waves of
expansion, contraction, and vibration are arrested there by the greater rigidity of the
riveted double-thickness of metal, which tends to localize the fatigue sustained by the
iron bear these points, and it also appears to increase the susceptibility to corrosive
action, since the furrows generally take the line of that fatigue, and are often deeper than
the spots on the plates." — Report of the Board of Trade {English), on Railway Accidents,
1855, p. 49.

U. S. Government Rules For Steam Pressures upon Boilers. To be applied to boilers
made since February 28, 1872 :

"Boilers, however, built of steel plates prior to this date, shall be deemed to have a
tensile strength of 75,000 lbs. per square inch, whether stamped or not."

" Multiply one-sixth the lowest tensile strength stamped on any plate in the cylin-
drical shell, by its least thickness in inches, and divide by the radius of the boiler in
inches, the result is the allowable pressure per square inch for single riveting, to which
add 20 per cent, for double- riveting.

" The hydrostatic test must be one and a half times the working pressure allowed.

Flues of IG inches diameter must not be less than one quarter inch thick, other
flues in proportion, and not less than three inches from the shell.

" A 42 inch boiler, single riveted of one-fourth inch iron, will safely bear a working
pressure of 110 pounds to the square inch, and must be tested to a hydrostatic pressure of
165 pounds to the square inch."

The Messrs. Wm. Crump & Sons, Iron Ship Builders and Boiler-makers of this city*
use the following proportions for the single-riveted joints of their boiler-plates.

PROPOPORTIONS OF SINGLE-RIVETED JOINTS.

Thickness

Plates.

\ inch.

3
8

Diameter

of
Rivets.

^ inch.

1 1

Pitch.

\^ inches,

Lap.

1^ inches.
1| «
2^ "

D. K. Clark gives the breaking strength of boiler-plates as follows:

Quality of Plate.

Best Yorkshire, .
" Staffordshire,
" American, .

Ordinai-y American,

Breaking Strength

Tons.

Breaking Strength

Pounds.

56,000 lbs.
44,800 "
69,440 "
60,480 "

♦Philadelphia, Pa.

1882.] THE LOCOMOTIVE. -185

*' Prof. Thurston, testing pieces of the wire cable of the Fairmount Suspension
Bridge recently taken down at Philadelpliia, after being in use about forty years, found
the iron to be fully equal in tenacity, elasticity, and ductility to the best wire of the
same size found in the market. This fact, and similar results obtained by other
experiments in 1878, led him to the important conclusion that iron subjected to the
ordinary strains of properly designed bridges, does not deteriorate with age." — American
Machinist, New Yorh, July 31, 1880.

John Anderson, Woolwich, 1872, p. 249:

" The three kinds of materials for boiler-plates stated in even numbers for tensile
strength are thus:

Steel, 90,000 lbs per square inch.
Iron, 50,000 " " " "
Copper, 34,000 " " " "

" The strength of iron in boilers is not much affected by the working temperatures up
to considerably over 400°, nor by low temperatures down to the freezing-point. But
when the temperature of the plates, through the absence of water or any other cause
rises much above 500^, then a change commences. Above 750° the tenacity diminishes
very rapidly, and when the plates become red-hot, they have lost fully the half of their
usual strength."

D. K. Clarke, Tables and Rules, p. 640, concludes — "The tensile strength of iron
plates of good quality is not materially impaired by punching, when done under proper
conditions." — p. 633. "Mr. J. Cochran found from experiments no loss by punching."

Wilson, on Steam Boilers, p. 63, says, " Rivet holes may be jjunched or drilled.
Both methods have their partisans — not decided by experiment which is best."

" Steam Boilers." W. H. Shock, Engineer in Chief, U. S. N:

p. 78 — " C. H. No, 1 shell iron will bear in the testing machine from 50,000 lbs. to
54,000 lbs. of tensile strain per square inch in the direction of the fibre, and from 34,000
lbs. to 44,000 lbs. across the fibre. ... It is used especially for the outside shell of
boilers."

p. 139 — " The tensile stress exerted by the maximum steam-pressure on any part of
a boiler should not exceed one-sixth of its ultimate strength. This factor of safety is
usually employed for parts of machinery subjected to the alternating stresses acting in
opposite directions. The steam pressure in a boiler cannot be considered as a quiescent
load, on account of the constantly occurring, and sometimes considerable fluctuations of
pressure due to various causes."

p. 140 — "It must be remembered that the strength of any structure is to be
measured by that of its weakest part, which in the case of boilers is the joint where the
sheets are connected."

p. 190 — " The experiments made by Fairbairn in 1838, have served, up to the present
time, as the basis of calculating the strength of riveted joints. According to these
experiments, the strength of a double-riveted joint is 70 per cent, of the strength of
the plate; and of a single-riveted joint 56 per cent. — Of these experiments it is neces-
sary to remark :

" Ist. That the results are only for the case in which the rivet-holes diminish the
•ection of the plate 30 per cent., while for the most part in practice, and particularly for
the single-riveted joint, that loss is very much greater.

" 2d. That the experiments were made on plates of only 0.224 inch thickness.

" 3d. That the experiments gave 46, and not 56 per cent., for the strength of the
single-riveted joint : the co-efRcient was arbitrarily increased by Fairbairn to cover certain
imperfections in the experiments."

186

THE LOCOMOTIVE.

[DECESfBER,

D. K. Clarke, Tables and Rules, pp. 636 :

"Experiments on various plate-joints made by "W. Bertram, at Woolwich Dockyard,
were published and discussed in 18G0. The thickness of the plates were f inch, -^^g inch,
and ^ inch, and in the single-riveted joint the net sectional area of the plates in the
line of rivets was 62.5 per cent, of the solid plate. The relative strength of the joints
of the f inch plate is given by him as follows:

Entire Plate, . . . . . . 100

Donble-riveted Joint, ..... 72

Single-riveted Joint, ..... 60

p. 203 — " The following table of the comparative strength of punched and drilled
rivet- work, containing the results of Kirkaldy's experiments, is taken from the "Pro-
ceedings of the Mechanical Engineers for 1872," in a paper read by W. R. Browne.

Diameter of

Rivets to

Thickness of

Plates.

Lap or Cover to

Titch to

Ratio of
Strencth of

Lap Joint.

Rivet Holes.

Diameter of

Joints

Rivets.

to that of Plates.
Per cent.

Single.

Punched.

Drilled.

Chain.

Zigzag.

Double.

Punched.

((

Drilled.

p. 366* — "Boilers have been tested by filling them completely with water and light-
ing a fire in the furnaces, tbe pressure being produced by the expansion of the water.

p. 448 — "In nearly every case in which severe overheating of portions of the boiler
has taken place previous to an explosion, it is reasonable to suppose that the loss of
strength in the overheated plates, or their strained condition when suddenly cooled off,
would be sufficient to cause rupture even with the ordinary working pressure, and while
an increase of pressure produced by the sudden vaporization of a certain quantity of
water, and a violent projection of water may have occurred simultaneously, and to a
certain degree intensified the disruptive force, it is the weakened condition of the
boiler which must be regarded as the primary cause of the explosion.''

Photograph of ax Explosion. — The United States engineers recently photo-
graphed the explosion of a wreck, which was blown to pieces by submarine charges of
dynamite, to ascertain, among other things, how long the spectacle really lasted. The result
was exceedingly interesting. There were six cameras employed, and the instant of the
explosion, as also the several instants when the exposures were made by shutter, were elec-
trically timed by a chronograph. A photograph taken one-tenth of a second after the
explosion showed the vessel broken and a column of water seventy feet high ; a photo-
graph secured 1.5 seconds after the instant of the explosion showed a column of water
one hundred and sixty feet high ; a third photograph, taken 2.3 seconds after, showed the
column at its full height of one hundred and eighty feet, while fragments of wTeckage
were in the air, but none had fallen to disturb the surface of the water; a fourth pictfure,
taken 3.3 seconds after, showed the column falling and the surface of the water disturbed ;
while a fifth photograph, secured 4.3 seconds after, showed that all was over. —
Oincinnati Artisan.

*Thi9 experiment to be safe, must be conducted as described, by filling the boiler completely with water.
We know of a case in which the boiler was only partially filled, fires were lighted, and a steam pressure gene-
rated safflcient to explode the boiler, and kill the unfortunate experimenter.— Editob Locomotitb.

1882.] THE LOCOMOTIVE. 187

Useful Notes on Specific Heat for Engineers and Firemen.

Tbe specific heat of any substance is the quantity of heat expressed in thermal units
which must be transferred to a pound of the substance to raise its temperature 1°
Fahr.

A thermal unit is the quantity of heat required to raise the temperature of a pound
of water from 39.1° to 40.1° Fahr.

The specific heat of different bodies varies greatly ; it is therefore necessary to select
some convenient substance and make its specific heat a standard by which that of other
bodies may be compared. Water is the most convenient substance for this purpose,
therefore it has been selected for such a standard, and the amount of heat required to
raise the temperature of a pound of it 1° Fahr., has been fixed upon as the standard
by which all quantities of heat shall be compared.

The reason why the temperature from 39.1° to 40.1° Fahr. is chosen is because 39.1°
is the temperature of greatest density of water, and its specific heat, as well as that of all
other substances, is different at different temperatures. Thus, it requires about one-
twentieth more heat to raise the temperature of a pound of water from 211° to 212° than
it does to raise it from 39.1° to 40.1°.

The following simple experiment will better serve to illustrate the nature of specific
heat than volumes of explanation :

The apparatus required consists of any vessel in which water may be boiled ; a com-
mon tea-kettle on a stove answers perfectly ; a pound of iron, preferably in sheet form,
rolled up into a loose spiral; an ordinary thermometer; and a small tin can — a common
quart measure answers every purpose; around this can wrap several folds of either cot-
ton or woolen cloth; tie a piece of twine or thread to your piece of iron, by which it
can be readily lowered into and lifted out of the kettle of boiling water; lower the iron
into the kettle, and leave it there until the water boils, so it may attain the temperature
of the boiling water, 212°; while it is thus being heated, weigh off a pound of water
and pour it into your tin can around which you have wound the cloth. This cloth is to
prevent a too rapid loss of heat. When the water has begun to boil, note with your
tliermometer the temperature of the cold water in the tin can ; lift the piece of iron out
of the boiling water and quickly lower it into the can of cold water ; agitate the water
briskly a few moments by moving the iron about by means of the thread, until you are
sure that the iron has cooled down to the temperature of the water; now note the tem-
perature of the water with your thermometer. We will suppose the original temperature
of the pound of water was 70°. If you perform the experiment quickly and dexterously
you will find that the hot iron has raised it to about 84^. Let us interpret the result.
A pound of iron, cooling from 212° to 84°, or 128°, has raised the temperature of a
pound of water from 70° to 84°, or only 14°. Thus we see that the capacity for heat of iron
is only about one-ninth that of water. After you have performed the experiment several
times, until you are perfectly sure of the result, try some other metal, lead or copper for
example, and compare the results. You will find that while the capacity of iron is about
one-ninth, that of lead is only about one-thirtieth, and that of copper about one-eleventh
that of water. These facts are expressed by saying that their specific heats are one-ninth,
one-thirtieth, or one-eleventh, that of water being taken as equal to 1.00.

The specific heats of many substances have been determined with great precision for
ordinary temperatures by scientific men. An examination of a complete table teaches us
many interesting things, among which we may note the following :

The specific heats of metals are low, ranging from one-thirty-third to one-sixth that
of water.

188 THE LOCOMOTIVE. [December,

Coal averages about one-fourth that of water.

Wood " " one-lialf " "

Stones " " one-fifth " "

The masonry of steam boiler furnaces is about one-fifth that of water.

Liquids vary from three-tenths to nine- tenths that of water.

Only one substance has a greater capacity for heat than water, viz. : bromine, 1.111.

The specific heat of a gaseous body depends upon whether it is taken with the gas
at a constant pressure, or constant volume, being greater in the former case than in the
latter. This, perhaps, will bear explanation.

The first law of thermodynamics is as follows : Heat and meclianical energy are mu-
tually convertible ; and heat requires for its production^ and produces hy its disappearance
mechanical energy in the propo7'tion of 17 'i foot pounds for each unit of heat. The law has
been rigidly demonstrated experimentally.

Now it is a familiar fact that if we take a cylinder fitted with a piston perfectly free
to move, introduce a quantity of any gas into it beneath the piston, and apply heat, the
gas will expand as its temperature rises, and raise the piston. Now in raising the piston
against the pressure of the atmosphere or any other resistance, wor^ must be performed,
and this work will be measured by the pressure on the piston, multiplied by the distance
through which it is moved. Bearing the above facts in mind it will readily be seen that
if we allow the gas to expand and raise the piston, as its temperature rises, the quantity
of heat required to raise its temperature 1° will be greater than would be required if
we fastened the piston down so it could not rise, in which case no work could be done,
and that the extra amount required in the first case would be simply that which, con-
verted into mechanical energy in accordance with the first law of thermodynamics, would
be sufficient to raise the piston. This has been proved to be true by experiment. The
true specific heat of the gas is held to be the amount required to raise the temperature of
one pound of it 1° degree when it is not allowed to expand.

The difference between the specific heat of air at constant pressure and constant vol-
ume was taken advantage of to calculate the mechanical equivalent of heat in the follow-
ing manner by Mayer, a German physician, forty years ago. Suppose we have a cylinder
with a piston just one foot square. For the jiurpose of simplifying the calculation we will
suppose the piston to be without weight, so that the only resistance to its motion is the
weight of the atmosphere on top of it. The weight of the atmosphere may be taken at
2,116 pounds per square foot. Let our cylinder be of sufficient height to contain one
pound of air at 32° and at the ordinary atmospheric pressure. This will occupy a vol-
ume of 12.387 cubic feet; and as our cylinder is just one foot square, our piston will be
just 12.387 feet from the bottom of the cylinder. Suppose now we have a second cylin-
der alongside the first, exactly like it, and filled with exactly the same weight of air at the
same temperature. We will secure the piston of this cylinder so it cannot move, leaving
the piston in the first one to move freely. Now apply heat to the air in both cylinders
until we raise its temperature 1°. The air in both cylinders now has a temperature of
33°. If we compare the amount of heat transmitted to the air in the two cylinders with our
thermal unit, we shall find that the air in the first cylinder has absorbed .2377 of a ther-
mal unit, wliile that in the second cylinder has absorbed only .1688 of the same quantity.
What does this difference mean ?

It is proved experimentally that air at 32° Fahr., when heated to 33° under constant

pressure, expands -j^j of its original volume. The air in our first cylinder then has ex-

12 386
panded and raised the piston so it now stands 12.387 ■+■ -■,,., = 12.412 feet from the

bottom of the cylinder, and in so doing has raised the piston against the atmospheric
pressure 12.412 — 12.387 = .025 feet. It has, therefore, performed work measured by

1882.] THE LOCOMOTIVE. 189

2,116 pounds raised .025 feet high = 53 foot pounds; which is the mechanical equivalent
of the extra heat added to the air in the first cylinder. This extra heat, as we have
seen, was .2377—1.688 = .0689 of one thermal unit.

Now, if the mechanical equivalent of .0689 of a thermal unit = 53 foot pounds, the
mechanical equivalent of our thermal unit is found by the following proportion:
.0689 : 53 : : 1 : 768. The exact determination of this quantity by other means gives 774
foot pounds, as before stated.

Another interesting and practically useful application of knowledge of specific heat is
seen in the water pyrometer. This consists of apparatus exactly like that described in
the first experiment for finding the specific heat of iron ; but the conditions of the ex-
periment are reversed. In the application of the pyrometer we have given the specific
heat of the water and the iron to find the initial temperature of the iron. By using the
metal platinum instead of iron we are enabled to ascertain the temperature of steam-boiler
furnaces which cannot be obtained in any other manner.

A table of specific heats is given the Locomotive for January, 1881. h. f. s.

How to Select a File.

On purchasing a file bear in mind that there are several qualities — first, second, third,
and fourth. The first quality is the best, and represents about seventy-five per cent, of a
file manufacturer's product. Firm names are always stamped on files before they are
tempered, and if, after they are finished, any of them are found to be poorly cut, or badly
tempered, the firm name is ground off and one of several fancy names, coined for all
qualities below the first, is stamped on each file belonging to certain quality. Thus, if a
file-maker should select the word "Jumbo" for his second quality files, all too jioor for
the first quality and too good for the third have "Jumbo" stamped on them. First
quality files only bear the name of the maker, while fourth quality generally bear no name
at all, and are seldom seen.

When you have thought of all these things ask the dealer for a first quality file, bear-
ing the name of well-known file maker. Select the heaviest file in the box (if there is
any difference in the weight of them), for a heavy file is generally truer than a light one
of nominally the same size, and is better for re-cutting ; a re-cut file, by the way, being
just as good as a new one. Take the file to the light and hold it in a horizontal position,
the point of it toward you. The teeth will now be pointed toward you, enabling you to
detect easily any imperfections that a bad file is heir to. If the conformation of the
teeth is irregular or uneven, or if the color of the file is not uniform, let it severely alone.
A spotted or mottled file denotes unevenness of temper. If, on the other hand, the file
presents a clean, white color, it denotes that the temper is even throughout ; and if, besides
this, it has regular and perfect teeth, and bears the maker's name, you may rest assured
that it is an excellent file. The best files are tempered at a low heat. Files of certain
sizes and numbers made since the 1st of June are of uniform weight, the file manufactur-
ers of the United States having agreed upon a standard of weights and sizes. — Age
of Steel.

Progress in Engineering.

Prof. Thurston, of the Stevens' Technical Institute, at Hoboken, N. J., delivered an
address at the recent meeting of the Mechanical Engineers, in which he reviewed the
state of engineering and its relation to the welfare of the community. He called attention
to the importance of more full knowledge of the sti'ength of members of full size in con-
struction. The increasing use of steel permits the building of bridges whose span was
not thought of by the last generation.

Modem methods of manufacturing in quantity and then assembling the parts to-

190 THE LOCOMOTIVE. [December,

gether afterwards has required a corresponding precision in the processes of work, and
a demand for standards of gauges and measurement. The talent and expense necessary
to produce universal gauges has been furnished under gorernment patronage in other
countries, but certam members have engaged in this work at their own risk, and the
enterprise of the Pratt & Whitney Company in this respect deserves the highest com-
mendation.

In the matter of machine design the result is not a hap-liazard coincidence, but a
matter of the application of engineering principles which attain the titness of means to
ends. The improvements in water-wheels at part gate was referred to as a result of great
commercial importance. IMilling as a process of attrition between stones has been super-
seeded by rollers which simulate the cracking of the kernel, the same as if reduced with
pestle in a mortar. Railway engineering, the applications of electricity, and the need
of further improvements in controlling cylinder condensation received appropriate men-
tion.

The address closed with a close treatment of the necessity of the law protecting in-
dustrial labor, and providing for its elevation by suitable public education. — Chicago
Journal of Commerce.

The Coal Industry.

The total product of bituminous coal in the United States for the census year closing
June, 1880, amounted to 40,81 1,4.j0 tons, of 2,000 pounds to the ton, divided among the
States as follows : Alabama, 322, 9o4 tons ; Arkansas, 14,778; Georgia, 154,084; Illinois,
6,080,614; Indiana, 1,449,406; Iowa, 1,422,883; Kansas, 763,297; Kentuckv, 985,857;
Marvlaud, 2,227,844; Michigan, 100,800; Missouri, 548,900 ; Nebraska, 200; North Caro-
lina^ 700 ; Ohio, 3,922,858; Pennsylvania, 18,004,988; Tennessee, 494,891; Virginia,
40,520; West Virginia, 1,702,570. The number of laborers engaged in mining this vast
amount of coal was 96,475, and the wages paid them were $80,707,059. There are only
two States that produce anthracite coal, Pennsylvania and Rhode Island. The former
produced 28,640,819 tons, and the latter 0,175 tons during the census year. The grand
total of coal produced was 71,067,567 tons, and the grand total of hands employed was
170,585. The census bulletin makes comparison with the English production. The
population of England is 25,000.000. The production of coal in that country in 1855 was
64,661,401 tons; in 1877, 136,179,968 tons, and in 1880, 146,818.152 tons. The number
of coUerits in England in 1880 was 8,380, and in the United" States, 3,264. The produc-
tion of coal in England, in an area about the size of Ohio, and with half the jiopulatiou
of the United States, is double that of this country. England is supposed to be aljout
up to its maximum, while this country is in the infancy of its coal development. There
are hardly tigurcs enough to compute its capacity in this respect, and its ))r()ductic)n for
generations to come will depend upon the demand. American manufacturing industries
depend on coal, and in this respect there can be no failure. There are several States in
which the deposits have been barely touched that are equal to the whole of England as
coal States. — Chicago Journal of Commerce.

The Iron Age says: The published report of the Master Car Builders' Committee on
standard freight and passenger car-trucks is exceedingly interesting, and the diagrams
which they give ot the car-truck trusses which they have tested are full of instruction to
the railway man. A large proportion of those which gave out shows that the upper
member of the truss is considerably too weak for the work it has to do, or rather that the
lower member can be considerably lightened, while the truck remained of the same ca-
pacity. Allen trucks, with the diagonal or arch bar three-fourths inch thick, in the test
crippled its upper member, while a similar truss built for the test with this member re-
dured to one-half inch, but with a seven-eighths inch top piece, showed pretty conclusive-
ly that this proportion was about what was needed for the work. The low truck of the
Chicago, Burlington &, Quincy road seems to have been the best proportioned of the
lot, breaking and crippling apparently taking place simultaneously. The standard truck
of .the New York Central evidently needs only a little moditication to make it one of the
strongest of any which were tested. The tests are of such a character as will enable car
builders to design a truck having about the same weight of metal in the truss, but with
an increase in the strength of probably one-half.

1882.] THE LOCOMOTIVE. 191

Notes and Queries.

F. A. H., refeiTuig to our article in the November Locomotive upon open heaters,
grease in boilers, etc., inquires if the objection obtains where the modern preparations of
petroleum are used for cylinder oils ? The objection is not as great as when animal oils
are used. Still, we find more or less difficulty. The deposit wiiich accumulates is of a
tenacious, waxy character, and is more frequently found adhering to the sides of the
boiler near the water line and around the upper tubes. We are a little troubled to ac-
count for this, but are of the opinion that it is the paraffine in the oil. It should be
borne in mind that a large proportion of the oil used in the cylinder is thrown out in the
exhaust. We will suppose that one pint of oil is used in a cylinder each day. If the ex-
haust is returned to the boiler there will have been carried into it in one month not
much less than three gallons. If the water is liable to be muddy or carries any consid-
erable quantity of vegetable matter, the oil will combine wnth it more or less, and certain-
ly give trouljle. Therefore, from a wide experience we advise that the exhaust be
utilized to heat the feed water, without bringing it in contact w'ith it, which cannot be
done unless a pipe or coil heater is used. Crude petroleum is very effective in removing
hard scale. But it should be put into the boiler when it is comparatively cool, after
blowing down and cleaning out the boiler. The crude petroleum may be j)ut in when
the boiler is being filled; it will rise to the surface of the water, and as the water rises
in the process of filling, the sides of the boiler will be washed by the rising oil on the
surface. We have been able to remove hard scale in this way which could not be re-
moved by any other process. Crude petroleum is volatile, and the amount of residuum
which would result from the quantity used in a boiler for such purposes would be so
small as to be harmless. We would not, however, advise the imdiscriminate use of crude
petroleum. If the water carries vegetable matter, or is liable to be muddy, other purgcrs
will be better. But for a hard lime scale we have found crude petroleum very efiective.
It will be observed that the conditions under which the oil is used in this case are dif-
ferent from tiiose where it is introduced in the exhaust from the engine. In the latter
case it is introduced into the water, which is at a high temperature, and may have more
or less impurity or scum on the surface; the oil readily combines with this, causing the
difficulties mentioned above. While in the former case the oil is introduced cold into
cold water, it washes, or " varnishes " the sides of the scale-covered boiler, penetrates it,
works its way between the scale and the iron of the boiler, and detaches it. Those who
have used petroleum to aid in removing a nut from a rusted bolt will understand its
operation. It eats out or dissolves the rust or oxide without injuring the iron. So with
hard scale, it works down between the iron and the sciile, eats out or lubricates the film of
oxide, and detaches it.

Forgot the Tunnel. — M. Aurelien Scholl has an amusing note on what he calls the
"forgotten tunnel." The other Sunday, being at Brussels, he was struck by the extreme
thinness of the earth covering the Braine le Comte tunnel, and wondered why the com-
mon sense of the engineers who made the line did not direct them to continue the cutting,
and thus avoid a subterranean passage. The mystery was explained to him by a Mons
advocate. When railways Avere in their veriest infancy the Belgian {lovernment sent a
party of engineers over to England to acquire experience in the construction of the new
iron highways, and on their return they were instructed to lay out the first railway in
that enterprising little kingdom. The work was accordingly put in hand, and on its
completion one of the engineers exclaimed : " Good heavens, w^e have forgotten the tun-
nel ! " The consternation was general, especially when it Avas remembered that there
was not a single line in England but could boast of a tunnel. What was to be done ?
Notliing l)ut to construct the long corridor at Braine le Comte, and when it was finished
the eartli was put on the top. The tunnel was then, says the witty Aurelien, the glory of
the line. — Cincinnati Artisan.

192

THE LOCOMOTIVE,

[December.

Incorporated
1866.

Charter Per-
petual.

Issnes Policies of Iiisnrauce after a Careful Iiispectloii of lie Boilers,

COVERING ALL LOSS OK DAMAGE TO

BOILERS, BUILDINGS, AND MACHINERY,

ARISIKG FROM

Steam Boiler Explosions.

THE BUSINESS OF THE COMPANY INCLUDES ALL KINDS OF STEAM BOILERS.
Full information concerning the plan of the Company's operations can be obtained at the

Or at any Agency.

J. M. ALLEIT, Prest. W. B. rRANKLIlT, Vice-Prest. J. B. PIEUCE, Sec'y.

Board of Directors.

J. M. ALLEN. President.

LUCIUS J. HENDEE, Prest. ^tna Fire Ins. Co.

FRANK W. CUENEY, Cheney Brothers Silk Manu

facturing Co.
CHARLES M. BEACH, of Beach & Co.
DANIEL PHILLIPS, of Adams Express Co.
GEO. M. BARTHOLOMEW, Prest. Holyolie Water

Power Co
RICHARD W. H. JARVIS, Prest. Colt's Fire Arms

Mannfacluring Co.
THOMAS O. ENDERS, of The ^tna Life Ins. Co.
LEVEKETT BRAINARD, of The Case, Locliwood &

Brainard Co.

Gen. WM. B. FRANKLIN, Vice-Prest. Colt's Pat. Fire-

Arms Mfg. Co.
GEO. CROMPTON, Crompton Loom Works, Wor

Hon. THOS. TALBOT. Ex-Governor of Mass.

NEWTON CASE, of The Case, Lockwood & Brainard
Co.

NELSON HOLLISTER, of State Bank, Hartford.

CHAS. T. parry, of Baldwin Locomotive Works,
Philadelphia.

Hon. henry C. ROBINSON, Attorney at Law. Hart-
ford.

GENERAL AGENTS. CHIEF INSPECTORS

THEO. H. BABCOCK,
CORBIN & GOODRICH,
LAWFORD & McKlM,
W. S. CHAMBERLIN,
J. L. SMITH.
H. D. P. BIGELOW,
0. C. GARDINER,
D. C. FREEMAN,
W. G. LINEBURGH,
GEO. P. BURWELL,
W. B. CASSILY,

R. K. McMURRAY,
WM. G. PIKE,
JOSEPH CRAGG,
WM. U. FAIRBAIRN,
B. M. LORD,
H. D. P. BIGELOW,
J. S. WILSON,
F. S. ALLEN,
J. H. RANDALL,
A. C. GETCHELL,
J. S. WILSON,

New York City.

Philadelphia.

Baltimore.

Boston, Mass.

Providence, R. I

Chicago, III.

St. Louis, Mo.

Hartford.

Bridgeport.

Cleveland.

Cincinnati.

OFFICES.

Office, 28.5 Broadway.
430 Walnut St.
" 10 So. Holliday St.
" 10 Pemberton Sq.
" 15 Weybof set St.
" 115 Munroe St.
" 404 Market St.
" 218 Main St.
" 328 Main St.
" 246 Superior St.
" 53 West Third St.

INDEX TO VOL. Ill, NEW SERIES.

A case of bagging resulting from the use of an open
heater, 25. ,«*■«.

Acoustics, notice of a new treatise on, by Prof. Anto-
nio Farvaro, 104.

A defective mud drum, and what it teaches us to

avoid, 145. . . ^ r, r^ -l^r

Address before the British Association, by Dr. C. VV.
Siemens, 150.

A ghost story, 55.

Air, things worth remembering about, 124.
" expansion of by heat, 124, 125, 188.
" pressure of, 124. . vi

" trapped by bulges in fire surface, causes trouble,

145.
" volume of, 194.
" weight of, 124.
Allen F. B., notice of appointment to position oi

'supervising General Agent, 165.
Amount of sediment deposited in boilers, 7.
Anaconda, a London, 135.
A new galvanometer for powerful currents, 88.
Area of chimney flues, 1.5. . . , i ^

" safety valves by government inspectors' rule, 4.
Arrangement of safety-valves, defective, 4, 131, 132.

<i " " proper, 130, 132.

.Art castings in iron, 174.
Automatic low-water alarms, dangers of, 6.

Avoid waste, 47. , , j • lan i-m

Balls, weight of copper, brass, lead, and iron, 169, 170.
gj^ ' « " " and lead, IbS.

Benzine as a de-incnistant, 55.
Blisters in boiler plate, 21.
Blowing out gauge cocks, 6.

Blow-off, 163. . J , . -f ,c-.

" proper construction and location of, 164.
Blue process of copyin" tracings, 93.
Boiler construction and setting, 33, 113. ^fl, 1'5^ 1/7.
" explosions, 1, 7, 10, 14, 23, 27, 3o, 36, 37, 40, 4»,

56, 57.
c< it classified list of in 1881,9.

ii « D. K. Clark on, 89.

n i« at Jewell Milling Co., 37.

« " in England in 1881, 40.

II " without mystery, 129.

" inspection on Sunday, 74.
" plate, blisters in, 21.
" " bulged, 22.

" " effect of drifting u|)on, 11, 12, 13.
« i< " high temperature on, 183, 184, J8o.

" " elastic limit of, 166, 183.
" " lamination in, 21.
" " phosphorus in, 149.

« strength of, 3, 38, 52, 54, 61, 62, 65, 110, 166,
167, 183, 184, 185.
" tubes, table of standard dimensions of, 119.
Boilers, how long may they be used, 44.
" insured with the Hartford Co., 180.
" not in use, how to prevent corrosion in, 95.
" safe working pressure for, 61.
" second-hand, 149.

" strength of, to resist transverse stress, 45.
" uuri''ht tubular, defects of construction, 18,

^ " nn, 162, 163.

« « <i proper construction, 18, 162.

177.
Braces, broken, 22, 147, 148.

" effect of sudden breakage of, 22.
" proper construction, 148.
Brake, the first style used on railroads 39, 40.
Brass, weight of, in bars, sheets, and balls, 168, 169, 170.
Bricks for boiler settings, porosity of, 31.

Bulged plates 22.

Burned " 145, 146 , . , ^ , „
Carbonate of lime, eliect of, in feed water, 26.
Car truck trusses, 190.
Cast-iron boiler lieads, thickness of tlat, 79.
Causes of boiler explosions, 10, 27, 41.
Check-valve, 111.
Chimneys, area of flues, 15.
" draught power of, 15.

" formula and tables for calculating dimen-
sions of, 15.
" horse-power of, 15.
" proportions of, 15.
Clark, D. K., on boiler explosions, 89.
Classified list of boiler explosions in 1881, 9, 10.
Coal production in 1880, 190. „ i ,o.

Comparator for end measures, the Rogers-Uond, 134.
Compound locomotive, Webb's, 42.
" steam engine, 159.
" tubular boiler, disadvantages of, 95.
Cooper, J. H., article from, 145.
Copper, weight of in bars, sheets, and balls, 108, 109,

170.
Copying tracings by blue process, 93.
c:<irrection of formula, 31.
Corrosion, 17, 18, 63.
Cotton, Wool, and Iron, 165.
Cut-oft", economy of, at different points, 175.
Dangers of using second-hand boilers, 149, 150.

« « , open heaters, 165.
Dan"erous tendency of automatic low-water alarms, 6.
Data, unclassified, by J. H. Cooper, 166, 181, 183.
Defective arrangement of gauge-cocks, 2.
" mud drum, 145.
« safety-valves, 4, 130, 131, 132,
" settings, 115, 116.
" rivets, 103, 104.
" furnaces, 21, 22, 23.
Deficiency of water, 6, 22.
Deposit in feed pipe, 159.

" " steam boilers, 24, 26.
Destructive explosion of a battery of boilers, 1.
Disregard of safe rules in boiler management, 117.
Drifting, its effect on boilerplate, 11, 12, 13, 94, 3b.
Ductilitv necessary to prevent injury by drift pin, IJ.
Duty ofthe steam engine, 171.
Earthquakes in 1881, 181.
Effect of extravagant promises, 94.

" sudden breakage of a brace, 22.

" feeding cold water into boilers, 35.

" repeated strains on materials, 61.

" suddenly opening a large steam-valve under

hiwh pressure, 89.
" explosives, 140.
Efficiency of gas engine, 157.

« " steam engine, 157, 171.
Elastic limit of boiler plate, 166, 183. ,„.„,i„inT

Electricity the best form of energy for transmitting
power, 151.
" for heating, 152.
Electric light, 153.

" railways, 1.52.
Emery, A. H., appropriation for, 13.

" testing machine, 39
End ofthe world, 126.
Engineering, progress in, 189.
Engine, first locomotive, 39.
" compound, " 42.
" smallest, " 62.

" largest, " HI.

" steam (see Steam Engine).

INDEX

En°nne, ^as (see Gas Engine).
Escape pipes for safety-valves, 175.
Expansion and contraction of boiler shells, 35.

" of air by heat, 104, 105.
Experiments on boiler explosions, 36, 49, 56.
Explosions, classified list of, for the year 1881, 9.
" in England in 1881, 40.
" cause of, 41.
" discussion of, 10, 17, 57.
" D. T. Lawson's experimental, 36, 49, 56.
" at Hamilton, McClure Sc Co., Zilwaukee,

Mich.
" in Dec. 1881,7.

" at Norwich, Ct., Rislev's Pi>fter\', 17.
« " Jewell .Milling Coi, Hrooklyn, N. Y., 37.
when there was no fire under the boilers,
14, 35, 55.
" in tlour mills, 63.
" without myster>', 129.
" photograph of, 186.
Explosives, eflect of, 140.
Extravagant promises, elfect of, 94,
Factors of safety 61, 166, 167.
Far\-aro, Trof. Antonio, notice of treatise on acoustics,

104.
Feed pipe, proper construction and location of, 35.

" " how to remove incrustation from, 95.
Feed pumps, rules for proportioning dimensions of,

141, 142.
Files, how to select, 189.
Filling boilers, 30.
Filters, reversing, 29.
Fire brigade, a German, 140.
" " the London, 136.
" insurance chart, 46.
Firing boilers, 30, 31.
Fish Commission, the U. S., 133.
Flour mill explosions^ 63.

Formula;, for computing dimensions of chimneys, 15.
" " breaking weight of boilers, 45.

" " locating points of support of boilers, 46.

' bursting pressure of boiler shells, 54.
' strength of riveted joints, 66, 90,

English Board of

Trade, 90.
" thickness of fiat cast-iron boiler heads

79.
" proportioning check valves. 111.
" expansion of air by heat, 124, 125.
" " dimensions of safety-valves, 4, 142.

Fractured plates, 35.

Fungi in wine vaults and coal mines, 138.
Furnaces, defective, 21.

Galvanometer for powerful currents, a new, 88.
Gas burners, regenerative, 126.
" cheapest form of, 155.
" coal used in manufacture of, 155.
" efiiciency of as fuel, 156.
" engine, advantages and efiiciency of, 156, 157.
" importance of, 154.

" manufacture, refuse products, value of, 154, 155.
" pipes. Table of standard dimensions, 118.
" theory of steam boiler explosions, 41.
•' the poor man's friend, 153.
" useful properties of, 153.

" value of by products of its manufacture, 154, 155.
Gauge cocks, defective arrangement of, 2.

" " how to blow out and care for, 6.

Getting up steam, 30, 73.
Ghost storj', a, 55.
Grate bars for sawdust, 141, 142.
Gravity specific. Table, 106.

Grimshaw's JilUlcr,. Millwright and Millfurnisher, 105.
Groovin£, internal, of plates and flanges, 22.
Gun, Krupp's muzzle pivot, 73.
Hailstone weighing 80 pounds, 148.
Hammering in steam pipes, 47.
Handholes in shells of upright boilers, 18, 162.
Heads of different individuals, sizes of, 137, 138.
Heaters, open, 25, 165.
Heat, expansion of air by, 124, 125.
" mechanical equivalent of, 14, 188.
" specific, 187.
HoUey, A. L., obituary, 25.
Hydrostatic test for boilers, 38, 53.
Hydrodynamics, Emerson's, 29.
Inches and sixteenths reduced to decimals of a foot

table, 139.
Inspection of boilers on the Sabbath, 74.
« " » value of, 21.

Inspectors' Reports, 5, 19, 20, 21, 34, 53, 71, 87, 102, 115,

131, 147, 163, 178.
Insuring defective boilers, 72.
Iron and steel, phosphorus in, 149.

" " " proiiuttion in 1881,110, 170, 171.
. " art castings in, 174.
Iron trade report for March, 1882,75.
Iron workSj running on tlie Sabbath, 74, 75.
Joule's equivalent, 14.
Johnson's riveting machine, 105.
Krupp's muzzle pivot gun, 73.
Lawson's, D. T., experimental boiler explosions, 36,

49, 56.
Lead, weight of, in bars, balls, and sheets, 168, 169, 170.

" pipe, weight of, 169.
Leakage at gauge-cocks, 7.

" " seams, 2,5, 79, 178, 179.
Life of the steam boiler, 44.
Limit of elasticity, 61, 166, 183.

" to which boilers should be tested, 54.
Locomotive, annual expense of running a, 139.
" engine, the first, 39.

" ■ " Webb's compound, 42.

" " the smallest, 62.

" " largest, 111.

" industry, the, 125.

Locomotive, The, 10, 180.

" " on the track, 89.

London fire service, 136.
Low water, 6, 22.
Lubricant, plumbago as a, 55.
Xoise in steam pipes, 47. _

Xon-conductors of heat, table of, 23. -
Xonsense written about steam, 44.
Xotes and Queries, 79, 95, 111, 141, 159, 191.
\otes on Specific heat, 187.
Xotice of books, papers, rejMjrts, etc.
Notice of boilers set by this Co., 150.

" " Boston Journal iif Commerce If Cation, Wool,

and Iron, 74, 165.
" " copies of Locomotive wanted of Aug., 1871,
72.
Notice of Emerson's Hydrodynamics, 29.

" F. B. Allen's appointment to position of

Supervising General Agent, 165.
" Fire Insurance chart received from Insur-

ance World, 46.
" Grimshaw's Miller, Millwright and Mill-

Furnisher, 105.
" Ililler's Report, Motional Boiler Ins. Co.,

Limited, 74.
" Longridge's Report, Engine Boiler, and Eni-

ployersi Liability Ins. Co., 117.
" ManufaKiirer and Builder, 165.

" Mechanical Engineer, 105.

" Meclianics, 31.

" Notes and Queries department, 57.

" Prof. Farvaro's Treatise on jicou-stics, 104.

" Report for 1881 of the Mdrkischcr Verein lur

Prufung und Uehericachung von Dampf-
kesseln in Frankfurt a. Ober, 88.
" Treasury Department circular, 110.

Obituary, A. L. Holier, 25.

" \Vm. S. Slater, 91.
Old boilers, 149.

" iron, 185.
Open heaters, 25, 165.
Overloading safety-valves, 78,79, 117.
Oxidation of iron, prevention of, 63.
Patching boilerSj 44.
Philadelphia juries, 13.
Phosphorus in iron and steel, 149.
Photograph of an explosion, 186.

Pipes for steam, gas, or water, table of standard dimen-
sions, 118.
Pipe thread, standard, 118.
" lead, weight of, 169.
Pirating, 74.

Plumbago as a lubricant, 55.
Pressure for steam boilers, safe working, 61.
Prevention of rust, 17, 18, 63.
Progress of engineering, 189.
Promises, effect of extravagant, 94.
Proportions for riveted joints, 65, 81, 97, 102, 104.
Queries, Notes and, 79, 95, 111, 141, 159, 191.
tiualities necessary for good boiler plate, 11.
Railroads, miles of, in various countries, 173.
Refusal of this company to insure unsafe boilers, 72.
Regenerative gas burners, 126.
Relative non-conductivity of various substances, 23.

INDEX

Remedy for waste in workshops, 47.

Repeated strains, effect of on boiler plate, 61, 62.

Report on Lawson's experimental boiler explosions,

49,56.
Report of Henrj- Hiller, National Boiler Ins. Co., 74.
" Michael Longridge, Engine, Boiler, and Em-

ployers' Liability Ins. Co., 117.
" the JUdrkischer Verein zur Priijung und

Uebertcachung von Dampfkessebi in Frankfurt
a. Ober, 88.
Reports, Inspectors', 5, 19, 20, 21, 35, 53, 71, 87, 102, 115,

131, 147, 163, 178.
Riveted joints, proponions of, 65, 81, 90, 97, 102, 104,
166, 184, 186.
" " strength of, 65, 81, 90, 97, 102, 104, 166,

184, isa

Rivets, table showing number of, in 100 pounds, 137.
Rules for ascertaining the cubic contents of irregular
bodies, 120.
" proportioning chimneys, 15.

" " safety valves, 4, 142, 143.

" " check valves, 111.

" " feed-purap cylinders,' 141.

" " riveted joints, 66, 90.

" thickness of flat cast-iron boiler heads, 79.

" placing points of support on boilers, 46.

" transverse breaking strength of boiler shells,

45.
" applying hydrostatic test, 54.

Rust, prevention of, 17,J8, 63.
Safety valves, escape pipes for, 175.

" how to calculate dimensions of, 4, 142,

143.
" improper construction of, 4, 130, 131, 132.

" over-loading, 78.

" proper construction, 132.

Safe working pressure for steam boilers, 61.
Scale and sediment, effects of, 7, 24, 26, 95, 159, 165.
Second-hand boilers, 149.
Settings, defective, 115.

" proper, 33, 113, lie.
Siemens' address before the British Association, 150.
Slater, \Vm. S., obituary, 91.
Smoke prevention, 31.
Specifications for boiler and fire-box steel (Penn. R. R.

Co.), 110.
Specific gravity, table, 106.
Specific heat, 187.
Standard time for the world, 77.

" for exact measurement, 134.
Staying power of tubes, 79.
Steam engine, duty of, 159, 171.

" efficiency of, 157, 171.

" compound, 159.

Steam, getting up, 30,73.
" jacket', 123.
" pipes, noises in, 47.

" " weight and dimensions of, table, 118.
" table of properties of, 120.
Steel for boilers, 110.
" production in 1881, 110.
" phosphorus in, 149.
Strain on boiler shells from buckled plates, 14.
Strength of materials, 45, 46, 61, 166, 167, 183, 184, 185,

186.
Superheater, 79.
Superheated-water theory of boiler explosions, 57.

Superheated-water, 121.

" " conditions necessary for, 58, 59.

Super\-ising General Agent (F. B. Allen), 165.
Sunday work, 74, 75.
Supports for boilers, how to locate, 45.
Table, proportions of chimneys, 15.

" relative non-conductivity of different sub-
stances, 23.
" proportions of riveted joints, 102, 166, 184.
" specific gravity, 106.
" weight and volume of water, 108.
" standard dimensions of steam, gas, and water

pipes, 11&
" " " " boiler tubes, 119.

" '■ pipe thread, 118.

" properties of saturated steam, 120.
" pressure, weight, and volume of air, 124.
" number of rivets in 100 pounds, 137.
" inches and sixteenths reduced to decimals of a

foot, 139.
" showing how much earlier a star passes a given

range on each succeeding night, loit.
" weight of lead, copper, and brass in sheets and

bars, 168.
" weight of lead, copper, brass, and iron balls, 169.
" " lead pipes, 169.

" " men and women, 173.

Testing boilers by hydrostatic pressure, 38, 53.

" machine at Watertown Arsenal, 13, 39.
Tliermodynamics, first law of, 188.
Thermometer, a super-sensitive, 127.
Time, a simple method of keeping correct, 158.
" solar, mean, sidereal, etc., 158.
" for the world, standard, 77.
Transit of Venus, 181.

Transmission of power by electricity, 151, 172.
Tubes, holding power of, 79.

" table of standard dimensions, 119.
Unclassified data, 166, 181, 183.
United States Fish Commission, 133.
Upright tubular boilers, 17, 101, 177.

" " " defects in construction, 18,

161, 162, 163.
" " " proper construction, 162, 177.

Valves, check. 111.

" safely (see Safety Valves).
Venus, transit of. 181.

Verdict of coroner's jury on Brooklyn explosion, 38,39.
Vessels lost during 1881, 75, 181.
Waste in workshops, 47.
Water, things worth remembering about, 108.

" weight, volume, pressure, temperature, and

various measures of, 108.
" pipes, table of standard dimensions, 118.
Wear and tear of boilers, 38.
Webb's compound locomotive, 42.

Weight of brass, copper, and lead in bars, sheets, balls,
and pipes, 168, 169, 170.
" men and women, 173.

" a million dollars in gold, silver, and nickel
coins, 123.
Whistle, the largest steam, 105.
Wiihler's experiments on effect of repeated strains on

iron, 01.
World, end of the, 126.
"X" traordinary, 91.
Zilwaukee explosion, 1.

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