Christiaan Huygens in Salomon Coster's clockmaker's shop, 1657.

Oil painting by Hugh Chevins, 1955, showing Huygens and Coster with their first pendulum clock. Christiaan Huygens (1629-1693), a Dutch physicist, designed the first clock controlled by the motion of a pendulum. Huygens based his clock on the observations made by the scientist Galileo (1564-1642) in 1583, when he first noted the constancy of a pendulum's period by comparing the movement of a swinging lamp in Pisa Cathedral with his pulse rate.