Wei Boyang's Zhouyi can tong qi is the earliest theoretical work of alchemy in the world. It is mentioned in the book that there were 600 records of fire by alchemists at that time, which shows that a lot of experience has been accumulated in alchemy with fire at that time. Bao Puzi, written by Ge Hong, an alchemist in Jin Dynasty, recorded and summarized the alchemy since Han and Jin Dynasties in detail. But the real alchemy originated from Qin Shihuang. Throughout his life, Qin Shihuang held crazy fantasies about fairy tales. According to Records of the Historian, Qin Shihuang became fascinated with the elixir of life and "the art of real people" when he was in his twenties. In order to cultivate immortals, at the instigation of alchemist Lu Sheng and others, Qin Shihuang even moved the palace into Xianyang underground palace, stayed indoors, marked the throne, and "received" immortals without being disturbed by outsiders. Such records can be found in several places in Historical Records. At least, Qin Shihuang was an alchemist before "pity Confucianism". And the rivers, lakes and seas where he took mercury as the tomb and the underground palace probably suggested that he believed that cinnabar mercury had magical power to help him continue to rule this "eternal" country after his death.