Oh gosh, I feel like this is a bit of comeuppance for anyone like me who thought this was going to be easier going than War and Peace!
I agree @SanFranBear , it seems that Hugo is assuming that his readers will know a lot of context around this battle which I don't have at all, and that's making it hard work. I'm honestly just skimming over at the moment.
Some highlights though
1 At the end of a long, long, long sentence full of names and events, listed one after another in a deliberate stream that feels at times like it will never end, this:
"..il ne s’en alarmait point, lui qui se croyait maître et possesseur de la fin ; il savait attendre, se supposant hors de question, et il traitait le destin d’égal à égal. Il paraissait dire au sort: tu n’oserais pas."
("..he was not alarmed if the beginnings did go astray, since he thought himself the master and the possessor at the end; he knew how to wait, supposing himself to be out of the question, and he treated destiny as his equal: he seemed to say to fate, Thou wilt not dare.")
The cadence of this, coming as it does the end of this huge long sentence, is just beautiful. I haven't been reading along in French but I had to pop over to the French edition to see how it reads in the original. Bravo to the (quite old-fashioned) translation here which poises this phrase perfectly.
2 "They listened to the rise of this flood of men. They heard the swelling noise of three thousand horses, the alternate and symmetrical tramp of their hoofs at full trot, the jingling of the cuirasses, the clang of the sabres and a sort of grand and savage breathing. There ensued a most terrible silence; then, all at once, a long file of uplifted arms, brandishing sabres, appeared above the crest, and casques, trumpets, and standards, and three thousand heads with gray mustaches, shouting, "Vive l'Empèreur!" All this cavalry debouched on the plateau, and it was like the appearance of an earthquake."
I'm not enjoying these war chapters but this is great stuff -so atmospheric! Also "debouched", cool word ("deboucher" in French, which apparently is most commonly used for uncorking a bottle or unclogging a drain).
3 I will admit I am only half-reading some of this but am I right that Hugo seems to be suggesting that the outcome of all of this is Fate? Whereas Tolstoy in W&P was more on the side of "it happened because it happened, there was no guiding hand"?