The next morning, McMurphy shocks the ward by singing. He asks an aide for toothpaste, but is told that ward policy won't allow the toothpaste to be unlocked because patients might use it at their own discretion. McMurphy baits the aide into a philosophical argument that points out the absurd and arbitrary nature of the ward policy, and resorts to using soap powder to brush his teeth. This also reminds Chief of how his father used to frustrate government agents by using the same rhetorical techniques.
McMurphy is confronted by Big Nurse as he exits the latrine. He greets her as "Miss Rat-shed," wearing what appears to be nothing more than a towel. He insists that someone has stolen his clothes during the night. Nurse Ratched realizes that McMurphy hasn't been issued his convalescent greens and chastises the aides, particularly one named Washington, for not doing their jobs, while McMurphy whistles "Sweet Georgia Brown." McMurphy winks at the nurse and removes the towel, revealing his whale-print undershorts to her. The shorts, he told Chief the night before, were a gift from a co-ed literature major. She gave him the shorts because she regarded McMurphy as "a symbol." The removal of the towel shocks Nurse Ratched, and she takes a while longer than usual to recover.
McMurphy's mispronunciation of Nurse Ratched's name indicates to the reader that her name indicates aspects of her personality. Rat-shed, obviously, has negative connotations, but the name is also similar sounding to "ratchet" and "wretched."
Chief writes that McMurphy's nonconformist behavior reminds him of his Indian father. Both men, he writes, liked to "get the goat" of other men by employing outlandish behavior and nonsequitors to baffle their more rigid opponents.
croon to sing or hum in a low, gentle tone; to sing (popular songs) in a soft, sentimental manner.