George Graham (clockmaker)

George Graham (7 July 1673 – 20 November 1751) was an English clockmaker, inventor, and geophysicist, and a Fellow of the Royal Society.

He was born in Kirklinton, Cumberland. A Friend (Quaker) like his mentor Thomas Tompion, Graham left Cumberland in 1688 for London to work with Tompion. He later married Tompion's niece, Elizabeth Tompion.

Graham was partner to the influential English clockmaker Thomas Tompion during the last few years of Tompion's life. Graham is credited with inventing several design improvements to the pendulum clock, inventing the mercury pendulum and also the orrery. He was made Master of the Worshipful Company of Clockmakers in 1722.

Between 1730 and 1738, Graham had as an apprentice Thomas Mudge, who went on to be an eminent watchmaker in his own right, and invented the lever escapement, an important development for pocket watches.

He was widely acquainted with practical astronomy, invented many valuable astronomical instruments, and improved others. Graham made for Edmond Halley the great mural quadrant at Greenwich Observatory, and also the fine transit instrument and the zenith sector used by James Bradley in his discoveries. He supplied the French Academy with the apparatus used for the measurement of a degree of the meridian, and constructed the most complete planetarium known at that time, in which the motions of the celestial bodies were demonstrated with great accuracy. This was made in cabinet form, at the desire of Charles Boyle, 4th Earl of Orrery.

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