The original drug memoir—a true 19th-century account of the pleasures and pains of addictionOnce upon a time, opium, the main ingredient in heroin, was easily available over the chemist's counter. The secret of happiness, about which philosophers have disputed for so many ages, could be bought for a penny, and carried in the waistcoat pocket—portable ecstasies could be corked up in a pint bottle. Paradise? So thought Thomas de Quincey, but he soon discovered that "nobody will laugh long who deals much with opium."