(1) He did this with a clepsydra , a vessel with a hole in the bottom and one in the top.(2) The device they used to ensure fairness was the clepsydra - u2018captured wateru2019 - and was a simple jar with a hole.(3) He designed a lotus clepsydra , that is a water clock which had a bowl shaped like a lotus flower on the top into which water dripped.(4) Of course the sun could not be used to tell the time at night and clepsydras or water clocks were in use in Egypt by 1500 BC.(5) Further back, the Chinese and the Romans used clepsydras (water clocks) at about the same time, although Egyptian sundials go further back.
