In a series investigating the history of drug use, we begin our trip tracing the rise of marijuana and synthetic amphetamines. Marijuana, from the Indian hemp plant, has been used worldwide as a source of rope, cloth, and paper; its medicinal qualities were first documented 4,000 years ago in China. But it's best known as the drug of choice of the 1960s. During WWII, US troops were given an estimated 200 million amphetamines to fight drowsiness and battle fatigue, and they're still used to fight depression.
