Pendulum clock

Clock regulated by a pendulum

A pendulum clock is a clock that uses a swinging weight known as a pendulum as its timekeeping element. The pendulum is an approximate harmonic oscillator that swings in a time interval that depends on its length, and that resists swinging at other rates. From its invention in 1656 by Christiaan Huygens, inspired by Galileo Galilei, until the 1930s, the pendulum clock was the world's most precise type of timekeeper.

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