Invention of the clock....

The earliest way of telling the time was by looking at the progress of the shadow cast by a twig stuck upright in the ground. Round about 1300 BC, this was developed by the inhabitants of ancient Egypt and Mesopotamia into the sundial. The sundial served for a thousand years until the invention of the clepsydra, or water clock. This was the first clock with moving parts. The mechanical clock was not invented until the 13th century and it was driven by weights. The spring-driven clock was invented sometime around 1450 AD.