In this passage, we're introduced to a young man named Patrick Prendergast. Although we're not told so right away, Prendergast will go down as a legendary figure in Chicago history: he's the man who assassinated the mayor of the city at the end of the World's Fair.

For now, however, Prendergast is just another young, mentally-ill man living in Chicago. The quotation suggests that Patrick has been "crushed" by Chicago itself—in other words, the big city pressures people into committing horrible crimes, effectively creating new criminals. The passage is written from the perspective of the naive city-dwellers of the 1890s—people…