Why, at the end of the chapter, does Jurgis once again find himself broke and out of work?

Jurgis beats Connor (the man who raped his wife), and he is once again arrested.

Jurgis is in Jail (see link). Because he has some money now, he calls Harper to help get him out of jail. When Jurgis tells Harper what he has done, Harper tells him that he cannot help him. Connor was a close friend of Scully’s and by beating him, Jurgis’s “pull had run up against a bigger pull, and he was down and out!” Harper negotiates the bail down to three hundred, which Jurgis pays, and he tells Jurgis that the only way to keep his freedom is to skip town. Jurgis boards a streetcar and makes his way to the other side of Chicago with only a few dollars left to his name.