Detail of clock face. Reconstruction of the pioneer pendulum clock designed by Christiaan Huygens (1629-1693), in 1656. Huygens commisioned the clockmaker Salomon Coster of the Hague to make the clock and a patent was isued in Coster's name in 1657. It was described and illustrated by Huygen in his book, 'Horologium' in 1658. Although Galileo had suggested the use of a pendulum to count the time, Huygen's design, where the dial and hands of a clock were controlled by a pendulum, was the first truly practical pendulum clock. Huygens attached a pendulum to the gears of a clock. The regular swing of the pendulum allowed the clock to achieve greater accuracy, as the hands are turned by the falling weight, which releases the same amount of energy with each tick.
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