Georges Graham
1649 - 1751
Georges Graham © mhe
English clockmaker and astronomer.
Member of the Clockmaker Company (CC.).
Free CC.1695.
Master CC.1722.
Member of the Royal Society in London (admitted in 1721) and member of its Council (admitted in 1722). Employee (from 1695), partner (Circa 1711) then successor of Thomas Tompion.
Married a niece of Thomas Tompion in 1696. Thomas Mudge was one of his disciples.
Astronomy
George Graham is known for having produced several astronomic instruments. He was also a generous man: in particular he gave financial support to John Harrison who, like him, worked to determine longitude using a precision watch onboard ships.
Key dates
1715
Invented the Graham escapement (deadbeat anchor escapement for pendulums).
1725
Improvement of Thomas Tompion's cylinder escapement for watches. It was the first cylinder escapement in history. Finalised in 1722, it was fitted on all Graham watches after 1726. The Frenchman, Julien Le Roy, who received one in 1728, recognised the superiority of the system.
1726
Invention of the Graham clock (mercury clock) which reduced the effects of temperature variations. Combined with the Graham escapement, this clock produced a degree of precision that was only to be exceeded with the development of the invar by Charles Edouard Guillaume in 1895. Clocks of this type were known as regulators.