Remembering History: Clepsydra or water clock, faience. Egypt, 4th century BCE. One of the earliest known time-keeping devices, water clocks had inner markings which revealed time passed as water ran out of them.

Clepsydra or water clock, faience. Egypt, 4th century BCE. One of the earliest known time-keeping devices, water clocks had inner markings which revealed time passed as water ran out of them.

Clepsydra or water clock, faience. Egypt, 4th century BCE. One of the earliest known time-keeping devices, water clocks had inner markings which revealed time passed as water ran out of them.