Watchmaker to the King.
Member of the Royal Society in London (admitted in 1738), of which he became a member of the Council for three years.
Invented a compensating pendulum, a variant of John Harrison's grid pendulum. Not perfectly smooth in its operation, it was not frequently used.
1728 to 1729
Adoption of Georges Graham's cylinder escapement which he helped to popularise.
Construction of equation watches and clocks.
Construction of the London Hospital clock.