The Ancient Greek Water Clock That Kept the Most Accurate Time for 1,800 Years
This article explores the history of the clepsydra, or water clock, specifically the advancements made by the Greek inventor Ctesibius in the third century BC. His design used a complex system of siphons, gears, and water wheels to maintain accurate timekeeping despite the changing length of daylight hours.
Why it matters
It provides historical context for the evolution of timekeeping technology and the ingenuity of ancient engineering.
in History , Technology | September 9th, 2026 Leave a Comment
Today, we’re surrounded by technologies we could justifiably describe as time thieves. In ancient Greece, those who wanted to know where their time was going consulted a device they called a “water thief.” The roots of the clepsydra, or water clock, go back as far as the sixteenth century BC, with evidence of such devices found in modern-day Iraq, Iran, and Egypt, and more ambiguous evidence unearthed in places like India and China. The mechanism in the earliest examples takes not much more complex a form than a bowl out of which water slowly drips, albeit not at a regular pace. That natural impediment to hydraulic timekeeping wasn’t corrected until the third century BC, when a Greek inventor called Ctesibius set about making his own improvements.
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