For Freddie Drummond, also known as Big Bill Totts, the slot represents the psychological cleavage between his two personalities. Like Dr. Jekyll, Freddie has a hidden alter ego, and like Jekyll, he has a noble reason for creating his dark side.
Dr Jekyll was doing medical research. Professor Frederick Drummond is doing sociology, researching his many books about the underclass. As a professor, “He was a very reserved man, and his natural inhibition was large in quantity and steel-like in quality.”
Nevertheless, there are indications that Freddie is not a creature of pure superego, that he truly hears the call of the wild, though faintly. He played football in college, and boxed. “He was noted as a boxer, but he was regarded as an automaton, with the inhuman precision of a machine judging distance and timing blows, guarding, blocking, and stalling.”
He is inhibited. Though extremely manly, Freddie dresses and speaks with formality and reserve. He lacks personal warmth. Perhaps he lacks life, north of the slot. “In his own world he was "Cold-Storage," but down below he was "Big" Bill Totts, who could drink and smoke, and slang and fight, and be an all-around favorite.”
As Big Bill, Freddie begins to adopt the values of the working class. He even falls for a working class woman, a leader of the labor movement. His libido takes over and he finds himself kissing her repeatedly in the door of a chop house, after the two of them dine on oysters.