On the Study of Ancient Chinese Mechanical Astronomical Clocks

This paper aims to explore the different systems that made up mechanical astronomical clocks in ancient China by analyzing and comparing historical records, related literature, and reconstruction work conducted by modern scholars. Before the development of the waterwheel steelyard clepsydra, power systems in astronomical clocks were believed to be waterwheels and floats, and the transmission elements likely consisted of ropes and heavy hammers or gear assemblies, which all together synchronized the celestial globe with movements of celestial bodies. With the development of the waterwheel steelyard clepsydra in the 8th century, time -keeping function was added to astronomical clocks, and the transmission system mostly consisted of gear assemblies. As the calendar system and mechanical skills advanced during the Song Dynasty, improvements were made on the waterwheel steelyard clepsydra, and astronomical clocks with multiple time -telling systems and different types of astronomical devices were developed. Influenced by western technology, time -telling mechanisms and astronomical devices used in astronomical clocks during the Yuan Dynasty gradually moved away from the use of waterwheels, and water-powered mechanical clocks were developed.