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Harrison, John |
Also found in: Hutchinson | 0.01 sec. |
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Harrison, John(born March 1693, Foulby, Yorkshire, Eng.—died March 24, 1776, London) British horologist. The son of a carpenter, in 1735 he invented the first practical marine chronometer. He followed it with three later instruments, each smaller and more accurate than its predecessor, and in 1762 his No. 4 chronometer was found to be in error by only five seconds (1 1/4′ longitude) after a voyage from England to Jamaica. Chronometers gave mariners their first practical method of fixing position at sea from celestial observations. See also Ferdinand Berthoud. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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