a self-educated English carpenter and clockmaker. He invented the marine chronometer, a long-sought after device for solving the problem of establishing the East-West position or longitude of a ship at sea, thus revolutionising and extending the possibility of safe long-distance sea travel in the Age of Sail. The problem was considered so important following the Scilly naval disaster of 1707, that the British Parliament offered financial rewards of up to £20,000 (£2.81 million) under the 1714 Longitude Act. Harrison came 39th in the BBC's 2002 public poll of the 100 Greatest Britons.
