John Harrison

Born: 3 April 1693, Foulby, United Kingdom.
Studied: Self-educated.
INVENTIONS

1.Marine chronometer:-

A marine chronometer is a precision timepiece that is carried on a ship and employed in the determination of the ship's position by celestial navigation. It is used to determine longitude by comparing Greenwich Mean Time, and the time at the current location found from observations of celestial bodies.

2.Gridiron pendulum:-

The gridiron pendulum was a temperature-compensated clock pendulum invented by British clockmaker John Harrison around 1726 and later modified by John Ellicott. It was used in precision clocks. In ordinary clock pendulums, the pendulum rod expands and contracts with changes in temperature.

3.Grasshopper escapement:-

The grasshopper escapement is a low-friction escapement for pendulum clocks invented by British clockmaker John Harrison around 1722.

Awards:- Copley Medal (1749) Longitude rewards (1737 & 1773).

Death:- 24 March 1776, Red Lion Street, London, United Kingdom.