The Seven-Per-Cent Solution

The second of the Sherlock Holmes novels, The Sign of Four, published in 1890, begins with the great detective unpacking a hypodermic syringe from its neat leather case, rolling up his sleeve and preparing to give himself an injection. ‘It is cocaine’, he says to the curious Dr Watson, ‘a seven-per-cent solution. Would you care to try it?’ Almost immediately after first appearing in print, Sherlock Holmes became (and remains) the 19th century’s most famous fictional user of cocaine. Early reviews of the Holmes stories were fascinated by the image of a private detective who had to be (as the reviewer for The Graphic put it) ‘either engaged in unravelling a first-class mystery, or in consoling himself for the want of one with cocaine’. When his creator Sir Arthur Conan Doyle died in 1930, one newspaper wryly observed that Sherlock Holmes was a man who ‘took cocaine before cocaine was fashionable’. But why did Conan Doyle light on cocaine specifically as Holmes’ drug of choice? And why were the Victorian public – at least at first – so ready to embrace both Holmes and his ‘seven-per-cent solution’?