How does Saul Bellow use imagery in Seize the Day?

Images of water and drowning permeate Seize the Day, reflecting Wilhelm's feeling that he is choking and suffocating. From the opening paragraph, in which Wilhelm rides the elevator that "sank and sank,"' and eventually reaches the lobby where the carpet "billowed toward [his] feet,"' Bellow presents a series of images that suggest water and its potential threat. Wilhelm's father presses his son to stop taking so many pills and to try hydrotherapy-"'Simple water has a calming effect'"-but Wilhelm's response is "'I thought ... that the water cure was for lunatics.'"