Huygens' Clocks

    In 1656, Christiaan Huygens built the world's first pendulum clock. It was far more reliable than any previous mechanical timepiece. For nearly 300 years, the most accurate clocks in the world all used pendulums, although many improvements were made to Huygens' design in that period.

    Christiaan Huygens was born in The Hague in 1629. His father, Constantijn, was a famous statesman, scientist, poet and musician. From 1645 to 1649, Christiaan studied at Leiden University and Breda before returning home to the Hague. There, he developed new ideas in mathematics, mechanics and optics. In 1655, he built a telescope with which he discovered Saturn's rings and one of its moons. He also designed and built the first working pendulum clock.

    In 1666, Huygens moved to Paris to become the director of the Académie des Sciences. While he was there, he published the classic work Horologium Oscillatorium, in which he gave a complete mathematical description of the pendulum and a description of his improved pendulum clock. In the same year, he produced a kind of engine which ran on gunpowder, although it didn't work very well.

    In 1675, he built a chronometer which used a balance wheel and a spiral spring instead of a pendulum. Robert Hooke had tried in 1660 to control a clock using a straight spring but Huygens' was the first to work properly. Balance wheels and spiral springs were used in almost all watches until the invention of the quartz crystal oscillator.

    Huygens returned to the Hague in 1681 and published his second classic work, Traité de la Lumière in 1690. In this book, he explained refraction by suggesting that light was a kind of wave. In 1693, he announced his theory of the conservation of mechanical energy.