Graham, George

▪ British watchmaker

born c. 1674, Horsgill, Cumberland, Eng.

died Nov. 20, 1751, London

      eminent English watchmaker and scientific instrument maker.

      Graham was apprenticed to a London watchmaker and came to the notice of the renowned watchmaker Thomas Tompion (Tompion, Thomas). After completing his apprenticeship, Graham joined Tompion's business, becoming his partner and successor and succeeding to his reputation as the best watchmaker of his time. He perfected the cylinder escapement designed by Tompion, which had been patented by Edward Barlow, William Houghton, and Tompion in 1695, and also perfected the dead-beat escapement, developed by Richard Towneley and Tompion in the mid-1670s. In 1721 Graham invented the temperature-compensated mercury pendulum, which was extensively adopted in the trade. In fact, when combined with the dead-beat escapement, such high-grade clocks were not surpassed in accuracy for more than a century and a half.

      During the terms of Edmond Halley (Halley, Edmond) and James Bradley (Bradley, James) as astronomers royal, Graham produced instruments to their specifications for the Royal Greenwich Observatory. He also made astronomical devices for the French Academy of Sciences (Sciences, Academy of), and, for Charles Boyle, 4th earl of orrery, he originated the device now called the orrery, a clockwork model showing the motions of the planets around the Sun.

Jonathan D. Betts

 

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