This watch is superbly finished: its balance staff was jeweled at a period when jeweling was far from common; it is made with the tampons in bronze bushings, sandwiching the steel impulse part; the balance spring is studded by a square pin to reduce deformation of the terminal part. The cylinder escapement, although known for forty years, was only applied by the best makers, of whom Graham was the most eminent. The repeating mechanism is made according to the Stogden system, which, though complex to make, was the most reliable at the time. Breguet himself subsequently used it in his early years, later devising his own system which was also a modification of Stogden's. Matthew Stogden was a workman of Graham. He invented his repetition system around 1730. George Graham (1673-1751).An eminent British maker, inventor of the dead-beat escapement (1715) and the mercury pendulum (1726), in 1725 he improved the cylinder escapement to its present form. He was admitted as a Freeman of the Clockmaker's Company in 1695 and immediately began working for Thomas Tompion. After Tompion's death in 1713, Graham continued in business at the same address, at the sign of the Dial and Three Crowns, Fleet Street, London, moving to new premises in 1720, the Dial and One Crown, where he remained until his death. Graham was elected Fellow of the Royal Society in 1721 and became a Member of the Council of that body in 1722. He became a Master of the Clockmaker's Company in 1722.