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Astro*Dictionary by Michael Erlewine





1 article for "Ctesibius"

Ctesibius [Astro*Index]


Greek inventor. Lived in Alexandria during the 2nd century BC.

Best known for his improvement of the Egyptian water clock, the clepsydra. A steady sequence of water droplets caused a float to raise a marker against a drum. By adjusting the drum, the day and night could each be divided into 12 equal "hours" regardless of the season. Thus, the day hours of summer were long, while the night hours were short. In winter, this situation was reversed.

See also:
♦ Time


Astro*Index Copyright © 1997 Michael Erlewine