Shen Kuo

Shen Kuo (1031-1095) served the Northern Song court as finance minister, head of the Bureau of Astronomy, and state inspector, aligning with the Reformist faction under Wang Anshi. In 1088 his Dream Pool Essays recorded the magnetic needle compass and the concept of true north via magnetic declination - discoveries Europe wouldn't match until centuries later. He planned a five-year project to map lunar and planetary orbits with colleague Wei Pu, but court opponents killed it. He improved the armillary sphere and water clocks, hypothesized land formation from marine fossils and silt deposition, proposed climate change after finding petrified bamboo in northern soil that couldn't grow it anymore, wrote of drydocks and pound locks, documented Bi Sheng's movable type printing, created raised-relief maps, and identified an unearthed crossbow part as a surveying tool Europe wouldn't know until 1321. He also kept notes on divination, the supernatural, and unidentified flying objects.