|This empirical study led to the discovery of gunpowder - a reaction
between Yin-rich saltpetre and Yang-rich sulphur.
In and around 133 BC, Li Shao-Chun got an emperor to financially support
his investigations. This 'wai-tan' form of alchemy led to the poisonings
of several emperors and other court members and eventually faded out by 400
BC. Gunpowder was first used in fireworks but it was adapted
for military use in the 10th century. Its formula had spread to Islamic
Asia by the 13th century and it was to stun the Europeans in the 14th century.
Gunpowder and fireworks were probably the two most important contributions
of Chinese alchemy, and vividly display the power of chemistry to do great
harm or great good.
The Chinese also developed 'nai-tan' or physiological alchemy which became popular in the 6th century. This led to the experimentation with body fluids such as urine, and which may have led to the isolation of sex hormones.
Most of the later Chinese alchemy was little more than chicanery and most of the stories of alchemists misdeeds have literary parallels in western and European literature.