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KF5JRV > TECH 12.06.16 15:09l 13 Lines 706 Bytes #999 (0) @ WW
BID : 4450_KF5JRV
Read: GUEST
Subj: Mercury Clock
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Sent: 160612/1351Z 4450@KF5JRV.#NWAR.AR.USA.NA BPQK1.4.65
Mercury Clock
Water clocks in the ancient world had one major flaw: the water running
through the clock was subjected to variations in temperature. It would
freeze in the winter and evaporate in the summer. Zhang Sixun, an
engineer during China's Song Dynasty, solved this important dilemma.
He was the first to use liquid mercury as the driving force in his
clocks. Mercury stays in liquid form at temperatures as low as
-39 degrees Celsius (-38.2 Fahrenheit). Because of this, Sixun's
devices did not freeze in the winter. Mercury also did not facilitate
the rusting of mechanical parts like water did. As a result, Zhang's
ingenious mercury clock could function smoothly throughout the year.
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