TOMPION, THOMAS

(baptized July 25, 1639, Northill, Bedfordshire, Eng.d. Nov. 20, 1713, London), most famous English clockmaker of his time, especially known for watchmaking improvements. Tompion is believed to have worked as a blacksmith until 1664, when he was apprenticed to a London clockmaker. Admitted to the Clockmakers' Company in 1671, he became a master in 1704 and was appointed clockmaker for the new Royal Observatory, in Greenwich, in 1676. Tompion worked closely with both the experimental physicist Robert Hooke and Edward Barlow, whose inventions contributed to improved clock and watch mechanisms. In 1675, following Hooke's design, Tompion made one of the first English watches regulated by a balance spring. In 1695, with Barlow and William Houghton, he patented the cylinder escapement (controlling device) that allowed use of a horizontal wheel, enabling Tompion to make the first of the flat and more compact watches. Working under the direction of Barlow, Tompion made an early repeating watch, a type that could be made to sound the nearest hour and nearest quarter hour by pushing two pieces extending from the sides of the watch. Tompion devised improvements in pendulum clocks that allowed portability without damage to the mechanism and facilitated adjustment. He constructed several clocks made to run for a year without rewinding, and he produced barometers and sundials, including pieces for King William III.