3. [W]herever I sat—on the deck of a ship or at a street café in Paris or Bangkok—I would be sitting under the same glass bell jar, stewing in my own sour air.

This quotation, from the beginning of Chapter 15, introduces the symbol of the bell jar. Esther explains that no matter where she goes, she exists in the hell of her own mind. She is trapped inside herself, and no external stimulation, no matter how new and exciting, can ameliorate this condition. The bell jar of Esther’s madness separates her from the people she should care about. Esther’s association of her illness with a bell jar suggests her feeling that madness descends on her without her control or assent—it is as if an unseen scientist traps her. Esther’s suicidal urges come from this sense of suffocating isolation.