# Dictionary of National Biography, 1885-1900/Evans, Frederick John Owen

​EVANS, Sir FREDERICK JOHN OWEN (1815–1885), hydrographer, son of John Evans, master R.N., was born on 9 March 1815. He entered the navy as a second-class volunteer in 1828. After serving in the Rose and the Winchester he was transferred in 1833 to the Thunder, Captain Richard Owen, and spent three years in surveying the coasts of Central America, the Demerara River, and the Bahama banks. Evans subsequently served in the Mediterranean on board the Caledonia (flagship), Asia, Rapid, Rolla, Dido, and Wolverene, passing through the different ranks of the ‘master's’ line, the officers then charged with the duties of navigation. In 1841 Evans was appointed master of the Fly, and for the next five years he was employed in surveying the Coral Sea, the great barrier reef of Australia, and Torres Straits. Beete Jukes, the geologist, was on board the Fly, and wrote an account of the expedition. Shortly after his return to England Evans married, on 12 Nov. 1846, Elizabeth Mary, eldest daughter of Captain Charles Hall, R.N., of Plymouth.
After a short spell of duty in the Isle of ​Man, Evans returned, in 1847, in the Acheron, to New Zealand, where he was engaged for four years in surveying the Middle and South Islands. During the Russian war he served in the Baltic, receiving the special thanks of Sir Charles Napier for his share in piloting the fleet through the Aland Isles.
By this time Evans had become known by his scientific qualifications, and in 1855 he was appointed superintendent of the compass department of the navy. He had at once to consider a difficult problem, the use of the compass in iron ships and armour-clads. It was necessary to deal with the disturbing elements arising from the iron and the magnetisation of the ships. Evans, in co-operation with Archibald Smith, F.R.S., accomplished the task satisfactorily. He contributed seven papers, all dealing with the magnetism of ships, to the ‘Philosophical Transactions’ of the Royal Society, of which he was elected a fellow in 1862.
In 1858 Evans prepared a ‘Chart of Curves of Equal Magnetic Declination,’ which was published by the admiralty. In 1860 he wrote a valuable ‘Report on Compass Deviations in the Royal Navy;’ this treated of the magnetic character of the various iron ships in the navy, and also of the Great Eastern steamship. His most important work was the ‘Admiralty Manual for Deviations of the Compass,’ of which Smith and himself were joint editors (1st ed. 1862, 2nd ed. 1863, 3rd ed. 1869). A simple account of the same subject was issued by Evans in 1870 as an ‘Elementary Manual for Deviations of the Compass.’ These have become standard textbooks, having been translated and adopted by all the great maritime nations.
At a later date Evans devoted much attention to terrestrial magnetism. He compiled the magnetical instructions for the observers on board the Challenger in 1872, and delivered a lecture on the ‘Magnetism of the Earth’ to the Royal Geographical Society in 1878. Evans was made a staff-commander in 1863, staff-captain in 1867, and full captain in 1872. In 1865 he was appointed chief naval assistant to the then hydrographer to the admiralty, Captain G. H. Richards, whom he succeeded in 1874. He was made C.B. in 1873, and K.C.B. in 1881. He was vice-president of the Royal Geographical Society from 1879 to 1881, and president of the geographical section of the British Association in 1876. In 1881 he contributed a paper to the latter body on ‘Oceanic or Maritime Discovery from 1831 to 1881.’
After resigning the post of hydrographer in 1884, Evans was appointed one of the British delegates to the International Conference held at Washington in 1885, to fix a prime meridian and universal day. He died at his residence, 21 Dawson Place, Pembridge Square, London, 20 Dec. 1885.
W. J. H.