- For other people named John Harrison, see John Harrison (disambiguation).
John "Longitude" Harrison was born 24 March 1693 in Foulby, West Yorkshire, England, United Kingdom (Nostell estate) to Henry Harrison (1665-1728) and died 24 March 1776 Red Lion Square London of unspecified causes. He married Elizabeth Barrell (c1695-1726) 30 August 1718 . He married Elizabeth Scott (c1700-1777) 23 November 1726 .
John Harrison, originally a carpenter, eventually solved the problem of accurate marine timekeeping, by which a ship at sea could determine its longitude. In 1765 he received half the twenty-thousand-pound prize offered by the Board of Longitude after building a clock that more than met the Board's requirements. After Royal intervention and an Act of Parliament, he finally received seven-eighths of the remainder in 1773.
Along the way, he had invented: the bimetallic strip, using two metals so that variations in temperature would not affect performance; the grasshopper escapement, an improved escapement design; and the caged roller bearing, to minimize the effect of friction.
Captain James Cook took one of Harrison's design chronometers on his second and third Pacific voyages, and on return in 1775 said it was "our faithful guide through all the vicissitudes of climates."
Siblings
| Name | Birth | Death | Joined with |
| John (Longitude) Harrison (1693-1776) | 24 March 1693 Foulby, West Yorkshire, England, United Kingdom (Nostell estate) | 24 March 1776 London | Elizabeth Barrell (c1695-1726) Elizabeth Scott (c1700-1777) |
| Mary Harrison (1695-) | |||
| Henry Harrison (c1702-1729) | |||
| James Harrison (1704-1766) | 1704 | 18 November 1766 Barrow upon Humber, Lincolnshire, England, United Kingdom | Thomasin Lamming (c1710-c1765) |
| Elizabeth Harrison (c1707-) | |||
Children
| Name | Birth | Death | Joined with |
| John Harrison (c1719-1738) | |||
| Name | Birth | Death | Joined with |
| William Harrison (1728-1815) | 20 May 1728 | 24 April 1815 | Elizabeth Atkinson (1728-) Susannah Hodgson (c1728-bef1786) Elizabeth Overton (c1750-) |
| Elizabeth Harrison (1732-) | 1732 England, United Kingdom | John Barton (c1730-aft1785) | |
Residences
Footnotes (including sources)
| ‡ General |
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| § Remains |
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