Emperors of Dreams, By Mike Jay

"If this revised text feels slightly less polemical," declares Mike Jay in his introduction, "it is not because my views have softened; they have simply become more commonplace." He is referring to "the anti-drug pieties... of our contemporary politics". Whatever one's feelings about the matter, Jay's fascinating, highly-informed study of recreational drugs in the 19th century shows that the desire to get stoned is nothing new.

He points out that the "small silver gas canisters and dew-soaked balloons" visible among the debris of pop festivals since 2005 have "unwittingly replicated" the waxed green silk bags utilised by the 20-year-old Humphrey Davy in 1799 for taking a puff of nitrous oxide. According to Davy, inhalation produces "a highly pleasurable thrilling in the chest and extremities", though it is to be hoped that present-day partakers do not repeat his experiment of first "drinking a bottle of wine methodically in eight minutes flat". Davy passed out for two hours.

Probing the history of opium, Jay notes that the Victorian urge to "police the boundaries of pleasure and pain" was a forerunner of today's War on Drugs. He explores the differing approaches to opium of Coleridge, who "almost always refers to it in the broader context of his physical and mental health", and De Quincey, who "developed a new and enduring image of opium; as an agent of both ecstatic pleasures and infernal pains".

If a certain literary allure is present with both opium and marijuana (Theophile Gautier's description of the food at Club des Hashishins is akin to synesthesia: "The water I drank seemed the most exquisite wine, the meat, once in my mouth, became strawberries"), this does not apply to ether, despite its advocacy by the Great Beast 666, aka Aleister Crowley. He maintained that by "breathing it as if it were the soul of your Beloved... you will perceive the heart of Beauty in every vulgar and familiar thing."

Jay says it is "a rather brutal high" and that "the hangover can last for days." He suggests that Robert Louis Stevenson's account of Jekyll's transformation into Hyde "could almost have been lifted" from Sigmund Freud's 1884 paper on cocaine: "I felt younger, lighter, happier in body; within I was conscious of a heady recklessness." The connection is, however, "implicit". With many leading figures suggesting the possibility of decriminalising certain drugs, Jay's book confirms the obvious: humans have always felt the urge to get high.