ANTHONY BURGESS, the novelist, has written a musical, ''The Blooms of Dublin,'' based on ''Ulysses.''

By ANTHONY BURGESS
If you drive North from Venice you will eventually come to Trieste. It has, because of its history, acquired a non-Italian aura to those who have merely heard about it or noted its position on the map, but, entering it, you will have no sensation of leaving Italy. There will be copies of Telegiornale and Cinzano and Campari in the bars, Agip garages and the confections of Motta. Address the Triestines in Italian, meaning the version of the mother tongue used on the radio or television, and they will understand you, though their version of Latin has an X in it, and they turn the Latin H into a G. The letter survives from young Lucia Joyce to her father James, beginning ''Go una bella balla'' - ''I have a lovely ball'' - and that ''go,'' which is ''ho'' on radio and television, is a typical Slav mutation. Trieste is partly a Slav-speaking town, which is why the neighboring Slavs of Yugoslavia have wanted it for their own.