Water Clocks Through History

Water clocks measure time by the flow of liquid.

Cuneiform tablets show Babylonian water clock usage.

Babylonian water clocks were cylindrical outflow vessels.

The oldest physical water clock is from ancient Egypt.

Egyptian clocks had twelve columns for seasonal hours.

Greek and Roman clocks added gears and automata for accuracy.

Ctesibius invented the first dial and pointer indicator.

China replaced outflow clepsydra with inflow type by 200 BC.

Zhang Sixun used mercury clocks to prevent freezing problems.

Su Song built a 30-foot tall astronomical clock tower.

Persian water clocks timed irrigation water shares fairly.

Zibad water clock was used until 1965 in Iran.

Water clocks were calibrated with sundials to improve accuracy.

Water clocks were replaced by mechanical verge escapement clocks.

Water clocks kept time for millennia in many cultures.