The water would start filling the bowl and it would sink it in a specific amount of time.
The Greeks called them ?Clepsydra? ? which translates as ?water thief?. It is believed that clepsydras were introduced from Egypt into Greece and, later, from there into Rome.

An improved version of the water clock – more elaborate and impressive mechanized – was developed by Greek and Roman horologists and astronomers around 325 B.C. This version had a face with a hand that pointed the hour as the water level changed. Sometime after 100 B.C., a Greek astronomer ? Andronikos ? built a stone water clock in the Athens marketplace. His water tower – known today as the Tower of the Winds ? showed the time with both sundials and mechanical hour indicators. It also displayed the seasons of the year and astrological dates and periods.

Another famous water clock was built in China by Su Sung in 1088 A.D. It was a tower over 30 feet tall and incorporated a few mechanisms. It had five front panels with doors that opened to show mechanical figurines that rang bells and held tablets indicating the hour.

OK, now it?s about time to finish this article.
2012 doomsday