Person: Gellibrand, Henry
Henry Gellibrand was an English clergyman who worked on magnetic declination and who made mathematical contributions to navigation.
Mathematical Profile (Excerpt):
 Gellibrand succeeded Gunter to the chair of astronomy in Gresham College, London in 1627.
 Gellibrand's most famous scientific discovery was the change over the years in magnetic declination.
 Gellibrand published his findings in A discourse mathematical of the variation of the magneticall needle together with its admirable diminution lately discovered (1635).
 Gellibrand, on the other hand, was observing in Gresham College.
 The time difference allowed Gellibrand to compute the difference in longitude between the two points of observation and he published the results in Appendix concerning Longitude (1633).
 Gellibrand also published logarithm and trigonometrical tables.
 Although only 39 years of age, Gellibrand retired in 1836 to Mayfield in Sussex.
Born 17 November 1597, Aldersgate, London, England. Died 16 February 1637, London, England.
View full biography at MacTutor
Tags relevant for this person:
Astronomy, Origin England
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References
Adapted from other CC BYSA 4.0 Sources:
 Oâ€™Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive