Fisher, George (DNB00)

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FISHER, GEORGE (1794–1873), astronomer, was born at Sunbury in Middlesex on 31 July 1794. One of a large family left to the care of a widowed mother, he received little early education, and entered the office of the Westminster Insurance Company at the age of fourteen. Here his devotion to uncongenial duties won the respect and rewards of his employers. His scientific aspirations had, however, been fostered by Sir Humphry Davy, Sir Joseph Banks, Sir Everard Home, and other eminent men, and he entered St. Catharine's College, Cambridge, in 1817, whence he graduated B.A. in 1821, M.A. in 1825. His university career was interrupted by his appointment, on the recommendation of the Royal Society, as astronomer to the polar expedition fitted out in H.M. ships Dorothea and Trent in 1818. The highest latitude attained was 80° 34', and both vessels returned to England disabled before the close of the year; but Fisher had made a series of pendulum experiments at Spitsbergen, from which he deduced the value 1/303 for the ellipticity of the earth. The results of his observations on the ships' chronometers were embodied in a paper read before the Royal Society on 8 June 1820, entitled 'On the Errors in Longitude as determined by Chronometers at Sea, arising from the Action of the Iron in the Ships upon the Chronometers' (Phil. Trans. cx. 196).

Fisher soon afterwards took orders, and qualified himself by formally entering the navy to act as chaplain as well as astronomer to Parry's expedition for exploring the north-west passage in 1821-3. A 'portable' observatory, embarked on board the Fury, was set up first at Winter Island, later at Igloolik, and Captain Parry testified to the 'unabated zeal and perseverance' with which Fisher pursued his scientific inquiries. He devoted much care to the preparation of the results for the press, and they formed part of a volume, published at government expense in 1825, as an appendix to Parry's 'Journal of a Second Voyage for the Discovery of a North-West Passage.' Astronomical, chronometrical, and magnetic observations were accompanied by details of experiments on the velocity of sound, and on the liquefaction of chlorine and other gases at very low temperatures, as well as by an important discussion of nearly four thousand observations on astronomical refraction in an arctic climate.

Fisher was elected a fellow of the Royal Society in 1825, and of the Astronomical Society in 1827, acted several times as vice-president of the latter body, and was a member of the council from 1835 until 1863. Appointed in 1828 chaplain to H.M. ships Spartiate and Asia he carried on magnetic observations in various parts of the Mediterranean, and on 24 Jan. 1833 laid a paper on the subject before the Royal Society, entitled 'Magnetical Experiments made principally in the South part of Europe and in Asia Minor during the years 1827 to 1832' (ib. cxxiii. 237; Proc. R. Soc. iii. 163). His theory of 'The Nature and Origin of the Aurora Borealis' was communicated to the Royal Society on 19 June 1834 (ib. p. 295), and to the British Association at Cambridge in 1845 (Report, pt. ii. p. 22). Founded on a close study of the phenomenon in arctic regions, it included the ideas, since confirmed, of its being the polar equivalent of lightning, and of its origin in a zone surrounding at some distance each pole. Auroras were thus regarded as a means of restoring electrical equilibrium between the upper and lower strata of the atmosphere, disturbed by the development of positive electricity through rapid congelation.

Fisher accepted in 1834 the post of headmaster of Greenwich Hospital School, and greatly improved the efficiency of the institution. He erected an astronomical observatory in connection with it, which he superintended during thirteen years, observing there the solar eclipse of 18 July 1860 (Monthly Notices, xxi. 19). At the request of Lord Herbert in 1845, he wrote text-books of algebra and geometry for use in the school, of which he became principal in 1860. His retirement followed in 1863, and after ten years of well-earned repose he died without suffering on 14 May 1873.

Besides the papers already mentioned Fisher presented to the Royal Society accounts of magnetic experiments made in the West Indies and North America by Mr. James Napier (Proc. R. Soc. iii. 253), and on the west coast of Africa by Commander Edward Belcher (Phil. Trans. cxxii. 493), and reduced those made on the coasts of Brazil and North America from 1834 to 1837 by Sir Everard Home (ib. cxxviii. 343). He contributed to the 'Quarterly Journal of Science' essays 'On the Figure of the Earth, as deduced from the Measurements of Arcs of the Meridian, and Observations on Pendulums' (vii. 299, 1819); 'On the Variation of the Compass, observed in the late Voyage of Discovery to the North Pole' (ix. 81); and 'On Refractions observed in High Latitudes' (xxi. 348, 1826).

[Monthly Notices, xxxiv. 140; Weld's Hist. of Royal Society, ii. 280; Royal Society's Catalogue of Scientific Papers.]

A. M. C.