The author offers an autobiographical account of opium use, tracing its origins in youthful experiences, the growth of dependence, and the physical and psychological effects of the drug. He describes vivid waking and sleeping phantasmagoria, examines social and medical contexts for opium use, and reflects on moral and therapeutic questions. Interspersed with personal reminiscence are observations about prevalence across social classes and a concluding effort to explain motives, consequences, and a hard-won attempt at self-recovery intended as caution and instruction.