In the early 1800s there arose in England a fashion for inhaling nitrous oxide, or laughing gas, after it was discovered that its use 'was attended by a highly pleasurable thrilling11'. For the next half-century it would be the drug of choice for young people. One learned body, the Askesian Society, was for a time devoted to little else. Theatres put on 'laughing gas evenings'12 where volunteers could refresh themselves with a robust inhalation and then entertain the audience with their comical staggerings. It wasn't until 1846 that anyone got around to finding a practical use for nitrous oxide, as an anaesthetic. Goodness knows how many tens of thousands of people suffered unnecessary agonies under the surgeon's knife because no-one had thought of the gas's most obvious practical application.