How were the Clocks Developed?

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Clocks and watches are used to measure time. Clocks can stand on their own or are hung on the wall, but watches are strapped on to the wrist. There have been many ways of measuring time for many thousands of years. Time was probably first measured by man several thousand years ago by observing the position of the Sun in the sky. Water clocks and sand glasses or hourglasses used changing levels of water or sand in a container to measure time. Candle clocks used to measure time with the burning of candles. Sundials used the movement of the shadow cast by the Sun. The first mechanical time piece was made in China in the 8th century. The clocks previously used springs or weights, but the modern ones use batteries for power. The digital watches show time by numbers on a small screen. 

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