Evans, Frederick John Owen

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Evans, Frederick John Owen

(b. London[?], England, 9 March 1815; d. London, 20 December 1885)

hydrography, geomagnetism.

Evans came of a naval family, his father, John Evans, being master, R.N. He volunteered for the navy himself at the age of thirteen. Having served on H.M.S. Rose and Winchester on the American station for five years, he was transferred to the survey ship Thunder under Captain Richard Owen. Here he began a long lifetime of work devoted to exact surveying at sea and to geomagnetism.

After three years around the coasts of Central America and the Bahamas, Evans served in a succession of ships in the Mediterranean; in the master’s line, he had responsibility for navigation. In 1841 he became master and senior surveying officer of H.M.S. Fly, assigned to exploration in the Coral Sea, around the Great Barrier Reef of Australia, and in the Torres Strait; his hydrographic work revealed a safe and easy passage through the strait and was an important contribution to the development of New South Wales. On 12 November 1846 he married Elizabeth Mary Hall of Plymouth, daughter of a naval captain. In 1847 Evans joined the Acheron and returned to the antipodes, where for four years he did hydrographic work on the coasts of New Zealand.

After distinguished service in the Baltic during the Crimean War, in 1855 Evans was appointed superintendentment of the Compass Department of the Navy; he was promoted to staff commander in 1863, staff captain in 1867, and full captain in 1872. He became chief naval assistant to the hydrographer to the navy in 1865 and himself occupied that important post from 1874 to 1884. He was appointed a companion of the Order of the Bath and knight commander in 1881.

Evans’ recognition as an outstanding scientist comes from his solution of the problems associated with compass navigation in iron and armor-plated ships and from his observations leading to the publication of a chart of curves of equal magnetic declination for the navigable world. In his work on compass errors, he had the collaboration of the eminent mathematician Archibald Smith; Evans as experimenter and Smith as theoretician made a formidable team. Together they solved a problem of great importance to the British Navy and to navigation in general at the time when iron ships were coming into wide use.

Some of Evans’ experiments were carried out on board the pioneer Atlantic steamship Great Eastern. The results led to proposals for the proper placing of the needles in the compass in relation to the soft iron magnets and in relation to the ship itself. Both induction effects and the magnetic field created by the metal were fully considered. An important indirect contribution to oceanography was the compilation of the magnetic instructions made by Evans and Smith for the great voyage of the Challenger in 1872–1876.

Evans’ contribution to science was recognized by his election as fellow of the Royal Society in 1862. He was also a fellow of the Royal Astronomical Society and a fellow and council member of the Royal Geographical Society. In 1884 he represented britain at the Congress of Washington for the establishment of a prime meridian.

BIBLIOGRAPHY

I. Original Works. Evans’ works include “Reduction and Discussion of the Deviations of the Compass Observed on Board of All the Iron-built Ships, and a Selection of the Wood-built Steamships in Her Majesty’s Navy,” in Philosophical Transactions of the Royal Society, 150 (1860), 337–378; “On the Effect Produced on the Deviations of the Compass by the Length and Arrangement of the Compass-needles; and a New Mode of Correcting the Quadrantal Deviation,” ibid., 151 (1861), 161–182, written with A. Smith; “On the Magnetic Character of the Armour-plated Ships of the Royal Navy, and on the Effect on the Compass of Particular Arrangements of Iron in a Ship,” ibid., 155 (1865), 263–324, written with A. Smith; “On the Amount and Changes of the Polar Magnetism in Her Majesty’s Iron-built and Armour–plated Ship “Northumberland,” ibid., 158 (1868), 487–504; Admiralty Manual for Deviation of the Compass (London, 1862; 2nd ed., 1863; 3rd ed., 1869); Elementary Manual for Deviations of the Compass (London, 1870); and “On the Present Amount of Westerly Magnetic Declination on the Coast of Great Britain, and Its Annual Changes,” in Philosophical Transactions of the Royal Society, 162 (1872), 319–330.

II. Secondary Literature. On Evans and his work see “Sir F. J. O. Evans,” in Nature33 (1886), 246–248; “Captain Sir Frederick J. O. Evans,” in Proceedings of the Royal Geographical Society, 8 (1886), 112–113; J. B. Jukes, Narrative of the Surveying Voyage of H.M.S. “Fly”Commanded by Capt. F. P. Backwood, in Torres Strait, New Guinea etc. During the Years 1842–1846, 2 vols. (London, 1847).

K. C. Dunham