Ge Hong completes the Baopuzi

Ge Hong (283 – 343 or 363/364) came from a southern gentry family of Jurong, near Jianye. Poor after his father’s early death, he copied borrowed books, learned the alchemical tradition of his great-uncle Ge Xuan from Ge Xuan’s disciple Zheng Yin and later married the daughter of his second teacher, the governor of Nanhai. In 303 he fought against the rebel Shi Bing, then went north to Luoyang in search of rare books and spent years in the south around Guangzhou before returning home. By his own account in the autobiography that closes the Outer Chapters, he had begun writing in his twenties and completed the work in the Jianwu era (317–318), the first years of Sima Rui’s rule; other works date it to about 320, and he later revised it. According to the Book of Jin, Sima Rui, then chancellor, took him on his staff and made him a Marquis Within the Pass for his services against the rebels.

The Inner Chapters argue that immortality can be attained by study and practice and survey the methods — breathing and gymnastics, diet, meditation, talismans and above all elixirs compounded from minerals, of which cinnabar is the highest. Ge Hong quotes earlier alchemical texts and describes operations he evidently knew at first hand: cinnabar, he observes, “when heated turns into mercury, and after further transformations turns back into cinnabar”, while a recipe with tin is perhaps the earliest known description of the preparation of “mosaic gold” (stannic sulphide). Joseph Needham called him the greatest alchemist in Chinese history. The Outer Chapters, in the Confucian tradition, discuss government, literature and the manners of the northern émigrés who had fled south after the fall of Luoyang.

Ge Hong also compiled medical handbooks. His emergency prescriptions advise steeping a handful of sweet wormwood (qinghao) in water and drinking the juice against intermittent fevers; this recipe led Tu Youyou to extract artemisinin at low temperature in 1972, work for which she shared the 2015 Nobel Prize in Physiology or Medicine.