First astronomical clock In the late 11th century the first astronomical clock was created by Su Sung, a Chinese astronomer, horologist and mechanical engineer. It was a hydro-mechanical (water-driven) tower clock in medieval Kaifeng. Features included a water-driven escapement as well as the world's first endless power-transmitting chain drive. Purposes of an astronomical clock, other than to tell the time, are providing information on astronomical events, such as showing the phases of the sun and moon, and displaying the zodiac and tide times. Read more about astronomical clocks in the Clocktime article The first timekeepers: Telling time before the pendulum clock. Further Reading Burstall, A. F., W. E. Lansdale and P. Elliott. 1963. ‘A working model of the mechanical escapement in Su Sung’s astronomical clock tower’ in Nature 199: 1242–1244. Lienhard, J. H. ‘No. 120: Su-Sung’s Clock.’ University of Houston. https://www.uh.edu/engines/epi120.htm. Image Credit Illustration of the inner workings of the astronomical clock tower created by Su Sung, Chinese astronomer. Internet Archive Book Images, No restrictions, via Wikimedia Commons
