clepsydra: Quick Facts

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Also Known As	water clock

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Ancient Egyptian alabaster water clock with a cylindrical shape and 12 carved columns, each containing 11 small false holes representing the hours of the night. The pale stone vessel is carved inscriptions and dates to the reign of Amenhotep III (1386 to 349 BCE).

A 14th-century Chinese clepsydra, or water clock, consisting of connected vessels used to measure time through the controlled flow of water. The device demonstrates an early method of timekeeping in China.

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