Cyrus Gordon’s The Common Background of Greek and Hebrew Civilizations is true gem and great example of interdisciplinary study. He examines parallel after parallel between Indo-European culture and Semitic culture. One very interesting section deals with the Sumerians and time-keeping. Gordon writes:
The greatness of Sumer can be measured in other spheres, too. Its sexagesimal system has reached us via the exact sciences. Our astronomers still divide the circle into 360 degrees with each degree divisible into 60 minutes and each minute into 60 seconds. The division of the hour into 60 minutes of 60 seconds each is also a legacy of Sumer. Whenever we look at a clock, we are reminded of our debt to Sumer.