Timothy Leary's advice to "tune in, turn on and drop out" was a 1960s exhortation to experiment with LSD, but humans had been consuming ergot alkaloids related to lysergic acid diethylamide for at least a thousand years. Opium has been around even longer with its medicinal uses being known to the Ancient Sumerians as long ago as 3400 BC. This is the first book to cover all of the major psychoactive drugs (both natural and synthetic) in one volume, and the only one to cover all aspects of t...