Su Song (born 1020, Fujian Province, China—died 1101, Kaifeng) was a Chinese scholar and administrative and financial expert in the imperial bureaucracy. His Illustrated Pharmacopoeia (1070) revealed his knowledge of drugs, zoology, metallurgy, and related technology. An armillary clock that he built to serve as the basis of calendrical reform was housed in a 35-ft (11-m) tower and powered by a waterwheel and chain drive; its mechanism anticipated techniques that would not be used in Europe for hundreds of years.