Who discovered how to tell time?

We figure time from the movements of the earth as it rotates on its axis and orbits the sun. Our ancient ancestors divided the da time into morning and afternoon long, long before the dawn of history. The first clock .watching, we think, was done with a shadow stick. When its shadow was shortest, the sun was at high noon. Through the ages, the methods of time telling improved.

The sun dial was invented. The passage of time was recorded by burning candles, by dripping water and by sand running through a gadget very like a modern egg timer. We do not know the names of these ingenious inventors   but if we should forget all we know about telling time, human .invent ors here and there would figure out the system all over again.