As those were particularly hot times in the general hullaballoo Bloom sustained a minor injury from a nasty prod of some chap’s elbow in the crowd that of course congregated lodging some place about the pit of the stomach, fortunately not of a grave character.
There are no more uses of "congregate" in the book.
Show samples from other sources
People congregated outside of City Hall to protest.
It was in the quiet at the end of the day, when we began to congregate in the open space before climbing into our caves.