Portable Gettysburg - Draft Version Part 2

The July 1 battle at Gettysburg proving as one-sided as it was, the action was to be taken up the 'next' day, July 2.  

In playing out the second day of the Battle of Gettysburg, I had to choose between beginning at daybreak, or waiting for Lt-Genl Longstreet to complete his peregrinations bringing his two available Divisions into line. Historically, it was not until 4:00pm that he was sufficiently satisfied to throw forward the Divisions of Hood and McLaws against Dan Sickles's III Corps. Meanwhile, George Pickett's Division was still somewhere back along the Chambersburg Pike.

For his part, apprehensive of the rising ground before him where he stood in the morning, Maj-Genl Sickles had pushed forward his troops as far as the Emmitsburg Road. There they took up positions in a peach orchard and an adjoining wheat field. Behind them, Trostle Woods and the Devil's Den offered refuge in the event of III Corps being pushed back.

Four o'clock arriving, the troops in place, Longstreet lurched forward, Hood on the right making for the Devil's Den and the Round Tops. To his left, McLaws aimed for the Wheatfield.  Birney's Division would have its hands full. Humphries's Division occupying the Peach Orchard and a length of the Emmitsburg road north of it was the target of Anderson's Division. The I Corps Artillery and half of III Corps' guns supported these attacks.

I didn't bother, by the way, with the 'oblique order' of Longstreet's method of attack, with brigades in pairs lurching forward at 15-minute intervals. For one thing, such intervals fell beneath the grain of the time scale I was using. Even at 1 turn per hour, the time scale was generous relative to the ground scale.

Meanwhile, A.P. Hill's remaining two Divisions: Heth and Pender struck towards Seminary Ridge and the Emmitsburg Road, and the Cemetery eminences beyond. Only half the III Corps artillery supported this attack.

At this point my first 'Note to Self'.  When I do this again, Seminary Ridge will be moved a hex-row westward.  It is far too close to Gettysburg and the Cemetery Ridge.  The Seminary itself will probably remain where it stands, prolonging the ridge's SW-NE alignment.

Although intended to 'go in' at the same time as the attacks from the west, R.S. Ewell's II Corps began rather poorly placed. Johnson's Division stood on the Hanover road, prepared to strike at Slocum's XII Corps lining Rock Creek south of Culp's Hill. But Early, close by the Hanover Road river bridge, and Rodes, in the northern outskirts of Gettysburg itself, were going to require some time to get into battle.

Another 'Note to Self' - bring all three Divisions, and the guns, closer by one hex to the Union lines - Rodes inside Gettysburg.  Probably Early should be standing at the road junction west of the river bridges; and Latimer's artillery on the rising ground (Benner's Hill) over which runs the Hanover Road.  Thos Brown's artillery should stand between the road junction and the town. We will soon see the effect of the piecemeal nature of Ewell's attacks later on.

I might also consider placing Powers Hill beyond Williams's southern flank.  It's not there because I don't have enough hill. 

The late start by Early and Rodes left Johnson's Division alone taking on Slocum's entire XII Corps. Once in action, Latimer's guns redressed some of the balance, but, in effect, it was 5 Strength Points (SP) against 6++. The loss of a quarter of his strength to gunfire before getting fairly to grips did not augur well for Johnson's prospects.

Whilst Slocum was fully engaged with Johnson, on Culp's Hill, Wadsworth's Division had the undivided attention of Early, supported by Brown's artillery. Nor could Doubleday, alongside on Cemetery Hill, lend a hand: Rodes's Division would soon be surging out of the town and up the slopes.

In the centre, Pender's Division was soon surging up Seminary Ridge, with Heth, perhaps a half-mile to their right where the ridge descended to the level of the plain, striking at Robinson. The battle was becoming general all along the front.

Standing in reserve close by the Baltimore Pike creek bridge stood Sykes's V Corps. He soon decided to bring his whole command on behind the Round Tops to form a reserve line behind the embattled III Corps.  Far to the south, the heads of Sedgwick's VI Corps column could just be made out, approaching up the Baltimore Pike.

McLaws and Anderson were very soon in close action. The former scored such heavy early successes that Birney had to draw his Division's reserves out of Devil's Den to maintain a front alongside Humphries. Anderson was finding Humphries devilish hard to shift. Now, here I gave the Union the benefit of cover, which might have been a mistake. The Wheat Field I considered open, but Devil's Den and the wooded Round Tops I intended also to offer benefits to the defender.  I'm inclined to thing that is much too generous to the Union, especially at my chosen ground, time and unit scales.

The fighting in the north was not going the way of the Confederates. Johnson's heavy losses induced Williams to strike across Rock creek on his own account. Nor was Early enjoying overmuch success to begin with.  The fighting on Culp's Hill was settling into a battle of attrition. Rodes was still some distance from the action.

A.P. Hill's attacks were also proving costly - to both sides. In carrying the Seminary Ridge, Pender was reduced to half strength. Heth was in no better state, though there remained little under Robinson's command apart from the Division HQ. All the same, it seemed that the Army of Northern Virginia was making progress on this front.

Mixed fortunes prevailed on Longstreet's front. More accurately things were going his way, pretty much; it was R.H. Anderson who was stalled in front of the Peach Orchard, and taking a beating. Humphries simply would not be shifted.

Humphries was divided between two hexes: 2SP within the orchard, 1+ and the Corps artillery to their right in front of Cemetery ridge, where stood Hancock's II Corps. At least Pegram's (III Corps)  and the Washington Artillery (I Corps) were discouraging any counter-attack from Humphries's right wing.

The sun was close to the horizon as Early finally swept Wadsworth from Culp's Hill, and Rodes began his assault upon Cemetery Ridge. Johnson had been driven well back from Rock Creek, but that left Geary's Division exposed to Early's follow-up attacks towards the Spangler's Spring. Pender and Heth were stalled along Seminary Ridge as Howard's Corps - such as who survived the previous day's debacle - held them off from further advances.

Reduced to shadows of themselves, Pender and Heth desisted from further attacks. Anderson's command practically destroyed (0SP remaining), McLaws swung left to drive Humphries at last from the Peach Orchard. Hood took over the assaults on Devil's Den, the remnants of Birney's Division fled to and over Little Round Top, with the Confederates in close pursuit.

At this point I unexpectedly had to bring this action to a halt and pack it all away.  But I was debating whether or not to play out one more turn anyhow. The four turns that had passed represented four hours' fighting.  It was now 8:00pm, and probably getting dark. I called it at this point.

For all its time limitations and the bits that could have been improved, this turned out to be quite an exciting action. Losses were very heavy - on both sides. Whereas the previous day, the Confederates won a crushing victory, this day losses were close to even, possibly favouring the Confederacy by only the slenderest of margins.

Nothing remained of Anderson's (III Corps) and Johnson's (II Corps) Divisions.  Heth and Pender (III Corps) were both reduced to 1SP each, and Early's Division's strength had been halved. Only Hood and McLaws (I Corps) and Rodes (II Corps) were close to full strength still.

For the Union, little remained of I, XI and III Corps; and Geary's Division of XII Corps had also been destroyed. But plenty of strength remained. Hancock's Corps had hardly been engaged at all, and then only at the end of the day; Sykes and Sedgwick hadn't even fired a shot.

One of the reasons for the heavy losses was that I allowed for few retreats. As units (formations) wore down, it seemed reasonable to allow a remnant to retreat - if it could. Units reduced to 0SP stayed on the table, represented solely by their commander or flag. Note, by the way, that I gave the Union formation flags only to Corps level, whilst CSA Divisions got them. The fact of the tiny size of many Union Divisions simply made giving them a flag most inconvenient. Giving them Division commanders seemed to me sufficient, and probably unnecessary.

When returning the days' losses halved overnight, they were for convenience allocated by CSA Division or USA Corps. They were, however totalled by Army and then halved. I counted two or three 'pluses', by the way, as 1SP.  So an army that lost, say 10SP and 5 'pluses' would get back 5+2=7SP. Unfortunately, the valuable piece of scrap pa document upon which I scribed the losses has been lost to history. I think I threw it out. Definition of trash: what you throw away forty-eight hours before you discover a use for it.

The set-up for 'Pickett's Charge' might have been promising. Johnson and Anderson could have been brought back to 2SP each, Early to 3SP and Heth and Pender also to 2+ or 3SP. The Union Army would have recovered a similar number of Strength points.

So far the experiment was a qualified success insofar as I have a pretty good idea what to do next time.

 

Portable Gettysburg - 'Draft' version part 1

Just on a month ago, 20 December 2023, I wrote up some prep work for a 'Portable Gettysburg'.  I played out at least some of the the thing just over a week ago.   The first pics here are of the battlefield laid out. I had to find some extra hill or ridge from somewhere - e.g. Herr and Cemetery Ridges: must tidy them up a bit. 

The Peach Orchard is a dead giveaway, ain't it though? My peach trees (made more than 30 years ago) are in blossom whatever the season!

 

Here are the armies laid out.  I included the cavalry of both sides, although the main action between them would not 'fit' on my table. Buford's 6-figure Division has a starting role on July 1; and part of Kilpatrick's late July 3. It seems that Gregg put in an appearance at some point, but without being engaged in the main action. Possibly the cavalry action could be reserved for my chessboard (8x8 square grid) as a separate action.

The action starts off promisingly with a 'continuity glitch', that is to say, I used the wrong figures to represent Heth's Division. This formation was split in two - the brigades of Archer and Davis leading (represented by 2+ Strength Points) with Pettigrew and Brockenbrough (2SP) following. Lining McPherson's Ridge stood Buford's Cavalry Division, 2SP, supported by cannon (1SP). 

Just as Buford prepared to hold his line, two army corps, J.F. Reynolds's Ist, followed by O.O. Howard's XIth came marching up the Emmitsburg road.  Somewhere behind them, off the table, was Dan Sickles's IIIrd Corps.

For his part, Harry Heth was supported by part of the III Corps artillery. Divided into two wings, Buford's right was driven off the ridge and routed (1SP destroyed), and part of the ridge captured. The second half of Heth's Division later followed up and united with the rest of the Division, where they were joined by the artillery.

Coming up behind them on the Chambersburg Pike, Dorsey Pender's Division was on the march, followed by the rest of the III Corps Artillery. By this time, Maj-Genl Reynolds was in action, Buford pulling out the remnants of his command back to Seminary Ridge. Wadsworth and Robinson counterattacked the front of MePherson's Ridge, whilst Doubleday occupied the rising ground - part of Oak Ridge - on the other side of the railway cut.

At this point the eagle-eyed reader will observe that the Confederate infantry have suddenly exchanged their blue kepis for brown slouch hats. Having 'colour coded' the CSA formations - blue kepis I Corps, black hats II Corps, and brown for III Corps, I simply forgot, and on came for the first corps to arrive: the blue kepis. 'Yarooh!' says I (or its rough equivalent - remember, this is a family show), and made the amendment.  


Meanwhile, Oliver Howard was bringing up his XIth Corps to form a line extending Reynolds's around the north of Gettysburg. The leading Divisions of Lt-Genl Ewell's II Confederate Corps were arriving, 'Old Jube' Early pushing down the Harrisburg road and Emmett Rodes to their right cresting Oak Ridge.

Suddenly, Doubleday was caught front and flank by Pender and Rodes. Howard led Schurz's Division to aid Doubleday, but even together they were overmatched. Barlow's Division found itself facing almost double their numbers in Early's command, supported as it was by half the II Corps artillery.

In short  order the whole of I Corps was being cut to ribbons, though Schurz was for a time holding his own.

During the course of this day's action, I was using the PW combat system ... sort of. Hits were resolved as 1-3 = -1 SP; 4-6 = 1 SP retreats. Not sure why the whole force within the target hex area weren't retreating, but it seemed right at the time. However, if and when detached SP/elements wished to rejoin, the smaller portion had to join the larger. In the pic below, two of Doubleday's Division had been forced back, leaving the commander himself with just one Brigade (SP). To reunite his Division, Doubleday had to pull back to where his other two brigades (SPs) stood.

For the July 2 action, I found this method wholly impractical, on account of a much more crowded battlefield. Although I tried to use it, eventually I found myself simply 'taking the loss' unless the ground behind were clear. I think now it were better simply to have the whole formation - or the part under close assault - retreat or else all hits are SPs lost. This is a decision for the next time I play out this battle. By the by, you will observe that I use the American 'Month-Day' convention of dating. I use this convention exclusively for ACW and AWI, or any other war games in which US Americans are my 'main' characters. For all other war games, I use 'Day-Month' (For my varsity lecture notes, I began early to label my pages with year-month-day as a six-digit string...very easy to keep things in order, that way).

At any rate, their own losses so far negligible, A.P. Hill's two Divisions drove Reynolds all the way back to Seminary Ridge, where they joined Buford's remnants. Of Howard's Corps, Barlow was driven fairly into the down - blocking Steinmetz's advance, leaving Schurz all alone against the might of three Confederate Divisions.

They could not stay there long. Back and through the town they fled.

Very soon the Confederates were pressing up against the north and west faces of the town, with Heth's Division attempting to storm the Seminary Ridge. East of the town, Early's Division faced Culp's Hill, as yet unoccupied, and not too far distant.

By now, the evening twilight was drawing in. Heth was stalled in front of Seminary Ridge, Pender still some distance off to his left, and the Corps artillery in support from McPherson's Ridge. Rodes was beginning to drive through Gettysburg itself from the Carlisle Road, and early poised to push on to the high ground south of the town.

Such was the situation as nightfall ended the action.

For some reason, my memory had conflated this action into what I thought would be a single posting.  But I find I took a few more pics than I had thought.  Somehow they fetched up in two different places in my archives. So Part 2 will have to await another time.

This first day's action turned out, much to my surprise, very one-sided.  Not only had the Confederates the numbers, the goddess Hexahedra smiled upon them with a benignity reserved solely for the Divinely favoured. Early lost an SP, and I think Heth lost merely his 'plus'. The Union lost both cavalry SPs, and there wasn't very much remaining of Reynolds's corps, either. Howard's, too, had been knocked about, though they had more often than not resulted in retreats through the town.

Now, I had Reynolds and Howard on the road at the beginning of the action, but the battle was to develop according to this schedule:

Turn 1 (08:00-9:30) - Buford in place on McPherson's Ridge, with 1SP cannon. Half of Heth arrives
Turn 2 (09:30-11:00) - Reynolds enters the action.
Turn 3 (11:00-12:30) - Howard forms line to right of Reynolds. 

                                   - Dice for arrival of Rodes: 5 or 6 required
Turn 4 (12:30-14:00) - Rodes and Early arrive, Rodes on Oak Ridge, Early down Harrisburg road
Turn 5 (14:00-15:30) -  Pender arrives with remainder of III Corps artillery down Chambersburg Pike
Turn 6 (15:30-17:00) -
Turn 7 (17:00-18:30) - I Corps Rally on cemetery Ridge.
Turn 8 (18:30-20:00) - Nightfall

At the end of the day - 'overnight' - formations would receive back half the previous days' SP losses. Two lost 'pluses' would count as a whole SP. I kept count of the respective losses by Confederate Division, and by Union Corps. I rather think that when I do this one again, I might have to 'pose code' the Union army corps, or perhaps use some sort of labelling. The question remained how I was to conduct the second day's action. 'Old Pete' Longstreet was up with two of his Divisions; Ewell and Hill, both, also had their 'missing' Divisions ('Alleghany' Johnson's and R.H. Anderson's) in hand. Should it begin at 8a.m - or wait until Longstreet's ponderous preparation were ready? 

I decided upon the latter, but therein lies a further problem: the time scale. Now, I had settled upon 1 turn to 90 minutes. That simply won't do. A three-move battle would take us from 4pm to 8.30 - well after sunset, though it might not yet have been full night. An hour per move isn't much of an improvement: 4 turns only.  

We'll end here with a little bit of an appetiser: early action on July 2.

To be continued...

Towards a Portable Gettysburg

Other projects for the moment hanging fire, I've been forced to allow this one to jump the queue. That nearly all that is posted here I did near-on a week ago. Certain little maintenance tasks about the house have contributed something to the present backlog, but a think the major snag lies elsewhere. Never mind.

Lt-Genl James Longstreet's I Corps CSA: the three Divisions
of Anderson, Pickett and Hood

Whilst reading a comment upon looking back at my 'Battle of Hughesville' post, I bethought myself to looking to my hex-grid table and my ACW figures and see how the Battle of Gettysburg would go. Let's start with the proposed table map:

The Portable Gettysburg Map. This is designed for the whole 
3-day battle, beginning with the clash between Buford's Union
cavalry and Heth's infantry Division.

What was now needed were forces commensurate with the size of the map. This really 'suck it and see' country. I have departed somewhat from many of the Portable Wargame conventions, but have retained the core concept. The tactical units, with one (likely) exception are infantry and cavalry Divisions and artillery battalions. The possible exception is J.E.B. Stuart's cavalry Division, of a size of the Union Cavalry Corps, but comprising 6 brigades with no subdivision. I reckon General Lee ought to have awarded Stuart his 'third star'.

Now, the forces comprised, roughly, as follows:

Union:

72,000 infantry: 7 Army Corps organised into 19 Divisions
13,000 cavalry: a single Corps organised into 3 Divisions
7,500 artillery: 370 cannon attached to Corps, plus an Army reserve park.

Confederate:

54,000 infantry (ratio 3:4): 3 Army Corps organised into 9 Divisions 
12,500 cavalry (call it even): 1 Division of 6 Brigades
6,000 artillery: 287 cannon (within 1 piece of exactly 7:9 ratio), all attached to Corps.

My first thought was simply to allocate 2 and 3 Strength Points (SP) to the Union Divisions (3 each to the Cavalry Divisions), and 4 to the Confederate. Artillery would be 2SP each, the Union getting 9 cannon, the Confederates 7. However, a bity of research led to a whole different allocation of figures and SPs.  Here's what emerged:

Maj-Genl Henry Slocum's small XII Corps USA:
Maj-Genl A.S. Williams commanding, 
2 divisions (Ruger and Geary) and artillery brigade.

Union Army:

Commander:  Maj-Genl G.G. Meade
I Army Corps: Maj-Genl J.F. Reynolds
    1/I Division: 3900 rounded to 4000 ... 8 figures SP2+*
    2/I Division: 3000                             ...6 figures SP2
    3/I Division: 4700 rounded to 5000 ...10 figures SP3+
    I Corps Artillery                                ...2 figures, 1 gun, SP2
II Army Corps: Maj-Genl W.S. Hancock
    1/II Division: 3300 rounded to 3000 ... 6 figures SP2
    2/II Division: 3600 rounded to 4000 ... 8 figures SP2+
    3/II Division: 3600 rounded to 4000 ... 8 figures SP2+
    II Corps Artillery                               ... 2 figures, 1 gun, SP2
III Army Corps: Maj-Genl D.E. Sickles
    1/III Division: 5100 rounded to 5000 ... 10 figures, SP3+
    2/III Division: 5100 rounded to 5000 ... 10 figures, SP3+
    III Corps Artillery:                              ... 2 figures, 1 gun, SP2
V Army Corps: Maj-Genl G Sykes
    1/V Division: 3400 rounded to 3000  ... 6 figures, SP2
    2/V Division: 4000                             ... 8 figures, SP2+
    3/V Division: 2900 rounded to 3000  ... 6 figures, SP2
    V Corps Artillery                                ... 2 figures, 1 gun, SP2
VI Army Corps: Maj-Genl J. Sedgwick 
    1/VI Division: 4200 rounded to 4000 ... 8 figures, SP2+
    2/VI Division: 3600 rounded to 4000 ... 8 figures, SP2+
    3/VI Division: 4700 rounded to 5000 ... 10 figures, SP3+
    VI Corps Artillery:                              ... 2 figures, 1 gun, SP2
XI Army Corps: Maj-Genl O.O. Howard
    1/XI Division: 2500 rounded to 3000 ... 6 figures, SP2
    2/XI Division: 2900 rounded to 3000 ... 6 figures, SP2
    3/XI Division: 3100 rounded to 3000 ... 6 figures, SP2
    XI Corps Artillery:                              ... 2 figures, 1 gun, SP2
XII Army Corps: Maj-Genl H.W. Slocum
   1/XII Division: 5300 rounded to 5000 ... 10 figures, SP3+
   2/XII Division: 4000                            ... 8 figures, SP2+
   XII Corps Artillery:                              ... 2 figures, 1 gun, SP2
Cavalry Corps: Maj-Genl A. Pleasonton
   1 Cv Division: 2752 rounded to 3000  ... 6 figures, SP2 (July 1 and 2)
   1 Cv Division: 4544 rounded to 5000  ... 10 figures, SP3+ (July 3 only) 
   2 Cv Division: 2664 rounded to 3000  ... 6 figures, SP2
   3 Cv Division: 3902 rounded to 4000  ... 8 figures, SP2+
   Cv Artillery:                                         ... 1 figure, 1 gun, SP1
Army Artillery: Brig-Genl H. Hunt
   Reserve Artillery                                  ... 3 figures, 1 gun, SP3

Totals:
148 infantry figures (SP43/[+12])*, 20-24 cavalry (SP7[+2]), 18 gunners for 9 guns (SP18).
Army totals: 186-190 figures, SP68(+14), excluding command SP


* Note:
Strength points (SPs) have been allocated per multiples of 3 figures (1500 men). Remainders a given a plus (+).  Units combat according to their nominal SP. However, units with a + to their SP lose the 'plus' as their first loss, and then their 'standard' SP thereafter. In effect, 1/I Division takes 2 dice in combat, but require 3 SP losses to be destroyed.

An early version of the Union Cavalry Corps.  See list for 
the changes. I've given Alfred Pleasonton a white horse...

Confederate Army:

Commander: Genl R.E. Lee
I Army Corps: Lt-Genl J. Longstreet
    McLaws's Division: 6900 rounded to 7000 ... 14 figures, SP4+
    Pickett's Division:    5500 rounded to 6000 ... 12 figures, SP4
    Hood's Division:      7400 rounded to 7000 ... 14 figures, SP 4+
    I Corps Artllery:                                           ... 4 figures, 2guns, SP4
II Army Corps: Lt-Genl R.S. Ewell
    Johnson's Division:  6400 rounded to 6000 ... 12 figures, SP4
    Early's Division:       5500 rounded to 6000 ... 12 figures, SP4
    Rodes's Division:      8000                            ... 16 figures, SP5+
    II Corps Artillery:                                         ... 4 figures, 2 guns, SP4
III Army Corps: Lt-Genl A.P. Hill 
    Heth's Division:        7500 rounded to 8000 ... 16 figures, SP5+
    Pender's Division:     6700 rounded to 7000 ... 14 figures, SP4+
    Anderson's Division: 7100 rounded to 7000 ... 14 figures, SP4+
    III Corps Artillery:                                        ... 4 figures, 2 guns, SP4
Cavalry Division: Maj-Genl J.E.B. Stuart**
   Hampton's Brigade:                                        ... 4 figures, SP1+
   Fitz Lee's Brigade:                                          ... 4 figures, SP1+
   Chambliss's Brigade:                                      ... 3 figures, SP1
   Jenkins's Brigade:                                           ... 3 figures, SP1
   Robertson's/Jones's Brigades:                         ... 6 figures, SP2
   Cavalry Artillery                                             ... 2 figures, 1 gun

Imboden's (Independent) Cavalry Brigade:  ... 4 figures, SP1+ 

Totals: 124 infantry figures (SP38[+6]), 24 cavalry (SP7[+3]),  14 gunners for 7 cannon (SP14)
Army totals: 162 figures, SP59(+9), excluding command SP.

Maj-Genl J.E.B. Stuart's CSA cavalry command**.

** Note on Stuart's command.
It's not being practical to move around 20 figures as a single block - though it would probably be fairly historical, as it happens, I've broken up the Division into its component brigades - combining only those of Robertson and Jones. It seems that Jones's command was subordinated to Robertson's in some way.  One could combine the brigades of 'Rooney' Lee and Jenkins - 6 figures, SP2 - a practical option.

Strength point system

As my ACW forces are mounted on strips of three figures, with occasional ones and twos, each multiple of three counts as a strength point (SP). The infantry and cavalry formations are multiples of three plus a remainder.

In combat, the number of combat dice is equal to the number of three-figure stands it has: its SPs. So a 14-figure Division has 4 combat dice for the 4 x 3-figure stands. 

However, when the formation takes hits, the non-multiple 'remainder' is removed first, before there is any further loss to its SPs. A 14-figure division that takes a damaging hit will lose the 'plus', and the one or two figures that make the plus. It will require a second hit to start reducing its nominal SP value. Hence a 14-figure formation's SP is given as 4+, and not 5. It has the equivalent of 4SP for combat, and 5SP for survivability.

As a formation incurs damage, the losses are removed. As it takes damage, a 14-figure Division will be reduced this way: 14 -> 12 -> 9 -> 6 -> 3 -> 0.  In the above pictures, the flags simply signify Divisional command, and is not added to the formations' SPs.  They have no SPs of their own, but are merely identifiers. A formation reduced to 0SP will have just the flag remaining, whereat it may be removed from the table.  

It is possible, however, that if the action continues into 2 and 3 July, that some losses might be recovered - stragglers and ambulant wounded perhaps returning to the colours overnight.  In that case, the flags of formations reduced to 0SP remain on the table where the rallied remnants may be gathered.

Scales:

The figure scales are very (very!) roughly 1 figure to 500 troops, and 1 cannon represents about 40 (41, actually) but, more specifically, 1 gunner to 20 guns.

The ground scale is indicated by the map - roughly 6 miles by 5, or just under 10km by 8.  This seems to indicate one 4-inch hex grid measures 2/3 km or 5/12 mile.  That is a scale of roughly 1:6666
I derive my time scales from the ground scale, taking the square root. 

That gives me a time scale of 1:80 approximately. (I do like what I call 'approximate arithmetic': it should be taught in schools).

If we imagine it takes 10 minutes to walk 2/3 km - reasonably brisk, but not exactly scorching shoe leather - then in 80 minutes, one may walk a little under 7km. Without going through the mathematics - something I discussed in this blog just over 9 years ago - I come down to an infantry move of 2 hexes the turn, and each turn an hour and a half (80 minutes, fudged to make the numbers nice).  As the battle was fought in early July, we're looking at 16 hours of daylight - 10 or 11 game turns, starting at daybreak. Just because it makes the numbers simpler I'd go for 10 daylight turns, and, optionally, 1 more in the evening's gloaming.

The prep work pretty much done, it remains sometime to play out the battle!

To be continued...