The House of Mirth
Eventually, Lily Bart receives a ten-thousand-dollar inheritance from her Aunt Peniston, which she arranges to use to repay Gus Trenor. Distraught by her misfortunes, Lily has by this time begun regularly using a sleeping draught of chloral hydrate to escape the pain of poverty and social ostracism. Once she has repaid all her debts, Lily takes an overdose of the sleeping draught and dies; perhaps it is suicide, perhaps an accident. That very morning, Lawrence Selden arrives to her quarters, to finally propose marriage, but finds Lily Bart dead. Among her belongings are receipts for her payments toward the debt she owed to Gus Trenor, proving that her financial dealings with Trenor were honorable and not evidence of an improper relationship. His realization allows him to feel sympathy and closeness for her, and he is clearly distraught by her death.
Chloral hydrate
In the conclusion of Edith Wharton's 1905 novel "The House of Mirth", Lily Bart, the novel's heroine, becomes addicted to chloral hydrate and overdoses on the substance:
She put out her hand and measured the soothing drops into a glass; but as she did so, she knew they would be powerless against the supernatural lucidity of her brain. She had long since raised the dose to its highest limit, but to-night she felt she must increase it. She knew she took a slight risk in doing so; she remembered the chemist's warning. If sleep came at all, it might be a sleep without waking.