Symbolism, Imagery, Allegory
The "bell jar" of the novel's title finds its parallel in the many places of confinement in the novel. The hospitals where Esther stays, Buddy's tuberculosis sanatorium, and the Deer Island prison that Esther visits are all places where people are separated off from the rest of society because they are considered in some way dangerous – mentally ill, infectious, or criminal. But these places are also disturbingly similar to the other, "normal" places in the novel, like Esther's mother's home or even a place as innocuous as the Amazon, Esther's dorm in New York City. All of these places point to society's need to group and divide people under rigid labels – "criminal," "insane," or just "virginal young woman."