George Graham, an English clockmaker, inventor, geophysicist and a Fellow of the Royal Society, was born in 1673 in the Cumberland town of Kirklinton.
Graham, like his mentor Thomas Tompion, moved to London in 1688 to work with Tompion. He later married Elizabeth Tompion, Tompion's niece.
Graham employed Thomas Mudge as an apprentice between 1730 and 1738, and Mudge went on to become a famous watchmaker in his own right, inventing the lever escapement— a significant advancement for pocket watches and later wristwatches.
Graham was well-versed in practical astronomy, having invented and modified a number of valuable astronomical devices. Graham designed the magnificent mural quadrant at Greenwich Observatory for Edmond Halley, as well as the superb transit instrument and zenith sector that James Bradley utilised in his discoveries.
He built the most comprehensive planetarium known at the time, in which the motions of the celestial bodies were exhibited with remarkable accuracy, and he furnished the French Academy with the apparatus used for measuring a degree of the meridian. Charles Boyle, 4th Earl of Orrery, requested that it be constructed as a cabinet.
When John Harrison arrived in London, Graham was introduced to him and became a long-time advisor and supporter of Harrison's work while he was working on building his own model of a Sea Clock “H1”.
When Graham and Harrison initially met, they spent several hours discussing clockwork, and Graham granted Harrison an unsecured, interest-free loan to continue his work. Graham then spoke on Harrison's behalf to the Board of Longitude, gaining more money from the Board.
The deadbeat escapement is frequently attributed to George Graham, who first used it in his precise regulator clocks around 1715.
In 1722/23, he made an important contribution to geophysics by discovering the diurnal fluctuation of the terrestrial magnetic field. He was also one of the first to observe a long-term secular shift in the compass needle's orientation.
During Tompion’s last few years, Graham was his partner. Graham is also credited for improving the pendulum clock's design, as well as developing the mercury pendulum and the orrery.
In 1722, he was appointed Master of the Worshipful Company of Clockmakers.