The earliest description of the use of opium as a recreational drug in China comes from Xu Boling, who wrote in 1483 that opium was ˉmainly used to aid masculinity, strengthen sperm and regain vigorˇ, and that it ˉenhances the art of alchemists, sex and court ladiesˇ. He described an expedition sent by the Chenghua Emperor in 1483 to procure opium for a price ˉequal to that of goldˇ in Hainan, Fujian, Zhejiang, Sichuan and Shaanxi where it is close to Xiyu. A century later, Li Shizhen listed standard medical uses of opium in his renowned Compendium of Materia Medica (1578), but also wrote that ˉlay people use it for the art of sexˇ, in particular the ability to ˉarrest seminal emissionˇ. This association of opium with sex continued in China until the twentieth century. Opium smoking began as a privilege of the elite and remained a great luxury into the early 19th century, but by 1861, Wang Tao wrote that opium was used by rich peasants, and that even a small village without a rice store would have a shop where opium was sold.