Knight, Gowin (DNB00)

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KNIGHT, GOWIN (1713–1772), man of science and first principal librarian of the British Museum, baptised at Corringham, Lincolnshire, on 10 Sept. 1713, was son of Robert Knight, vicar of that place, and of Elizabeth his wife. His father, a virtuoso who collected coins and medals, was appointed in 1724 to the vicarage of Harewood, near Leeds, where he remained until his death in 1747. According to the Wilson MSS. preserved in the Leeds Free Library, Knight was educated at the Leeds grammar school. He matriculated at Oxford from Magdalen Hall 5 April 1731, and held a demyship at Magdalen College from 1735 to 1746, proceeding B.A. 20 Oct. 1736, M.A. 22 June 1739, and M.B. 11 Feb. 1741–2. He afterwards settled in London and is said to have practised as a physician. In 1749 he was living in Lincoln's Inn Fields; he removed to a house in Crane Court, Fleet Street, about 1750 (cf. Nichols, Literary Anecdotes, v. 534).

Knight began the magnetical researches which gave him his reputation before 1744. His attention was directed to the subject by witnessing the effects of a flash of lightning upon a ship's compass, and the first results of his labours were presented to the Royal Society in 1744 (Phil. Trans. xliii. 161), when he exhibited some bar magnets of great power, and performed some experiments which proved that he was in possession of an entirely new method of magnetising bars. A paper read by him in 1745 (ib. xliii. 361) discusses the various positions of the poles of magnets. In recognition of the value of these researches the Royal Society in 1745 elected him a fellow, and in 1747 the Copley medal was awarded to him. He found a ready sale for his magnets, and in a further series of papers laid before the society in 1746–7 (ib. xliv. 656–72) dealt more particularly with the theoretical aspects of the question. He withheld a full disclosure of his methods of operating for fear of injuring the sale of his magnets, but he soon found in John Canton, who had also begun the manufacture of artificial magnets, a formidable rival [see Canton, John]. Knight's papers on magnetism were collected and published separately in 1758, with notes and additions by the author. It appears from T. H. Croker's ‘Experimental Magnetism’ (1761), p. 8, that Knight issued proposals in 1760 for publishing by subscription an extensive work on magnetism, in two volumes 4to, but the plan was never carried out. After his death his friend Dr. Fothergill read a paper before the Royal Society (ib. 1776, lxvi. 591), in which Knight's methods of magnetising were more fully disclosed. The paper also contains a description of his ‘magnetic magazine’ or battery, which was for many years in the possession of the Royal Society, but is now missing. In 1779 Benjamin Wilson (ib. lxix. 51) gave an account of Knight's method of making artificial loadstones, which consisted in cementing finely divided metallic iron into a solid mass by the admixture of linseed-oil varnish.

Knight's attention had meanwhile been turned to the mariner's compass, and in a paper read before the society in 1750 (ib. xlvi. 505) he stated that he had examined several compass-needles obtained from the best makers, and found them all defective, being either of feeble directive power or absolutely incorrect as regards direction. These defects were due to the shape of the needles, all of which were possessed of four poles. He recommended a plain rhomboidal bar, and he also suggested improved modes of suspension. Some further improvements already made in Knight's compass by Smeaton were communicated to the society at the same time.

Knight brought his improved compass under the notice of the admiralty, and there is an entry in the official minute book under date 4 April 1751 to the effect that the navy board and the Trinity House authorities had been consulted and various experiments made with the improved compass and bar magnets. Compasses were ordered to be supplied to the Glory, bound for Guinea, the Rainbow going to Newfoundland, the Swan sloop bound to Barbadoes, and to the Vulture and Fortune sloops in the Channel. On 11 Sept. in the same year there is a further order directing the captain of the Fortune to receive Dr. Knight on board at Harwich and to sail northwards according to his directions, for the purpose of experimenting with the new compass. He was accompanied on the voyage by Smeaton (see Annual Register, 1793, Chronicle, p. 256). The results of the trials appear to have been satisfactory (though the captain's reports cannot now be found), and by a minute dated 24 June 1752 the board recommended that Knight should be paid 300l. It appears from this minute that the compass had already been brought to the notice of the board of longitude, probably with a view to its use in determining the longitude by observation of the magnetic variation, but the minutes for this date are missing from the records of the board preserved at the Royal Observatory, Greenwich. There are other entries in the admiralty books relating to the matter, and it appears that Knight's instrument gradually came to be the standard compass for the royal navy. They were also used in the better class of merchant ships. The compasses were made, under Knight's direction, by George Adams the elder [q. v.] of Fleet Street, the mathematical instrument maker. Knight was in the habit of certifying each instrument by signing his name on the card. There is a compass preserved in the admiralty compass department at Deptford certified in this way. It is stated by Captain Flinders in a manuscript diary, now in the possession of his descendant, Mr. Flinders Petrie, that Knight occupied the position of inspector of compasses to the admiralty, and that J. H. de Magelhaens was his successor in the office. Captain Flinders had every opportunity of knowing the facts, but the statement is not borne out by the admiralty minute books. In 1766 Knight took out a patent (No. 850) for some further improvements in compasses, the main object of which was to check the vibration, the card and box being made to oscillate in equal times, so that the card always remained parallel to the glass. A reflecting azimuth compass is also described in the specification of this patent. The value of Knight's services to navigation does not seem to have received adequate recognition. A useful summary of Knight's work in this department of science is given in Snow Harris's ‘Rudimentary Magnetism,’ 1852, chap. ix.

Knight was an unsuccessful candidate for the post of secretary to the Royal Society in 1752, in opposition to Dr. Birch. But when the British Museum was first established at Montague House, Bloomsbury, in 1756, he was appointed principal librarian. The salary attached to the office was only 160l. per annum, but the librarian was allowed to act also as ‘receiver,’ and received on that account an additional 40l. a year. He presented to the museum a set of his magnetical apparatus (which were shown in the early days of the institution, but cannot now be found), the Copley medal which he received from the Royal Society in recognition of his magnetical researches, and a collection of coins and medals bequeathed to him by his father. There are two papers in his hand among the Sloane MSS., one relating to alchemy and the other being notes of lectures on surgery, but without any indication of the time and place of delivery.

He seems to have led a secluded life, and during his later years was involved in financial difficulties. Dr. John Fothergill on one occasion advanced him a thousand guineas to save him from impending ruin due to some disastrous mining speculations (Fothergill, Works, ed. Lettsom, vol. i. p. ciii), and Knight was never able to discharge this liability. By his will, dated 9 April 1772, he left everything to his ‘good friend and principal creditor, John Fothergill of Harpur Street,’ whom he appointed sole executor. It appears from the official records that Knight died at the museum on 8 June 1772 (not 9th, as in Gent. Mag. 1772, p. 295). His burial is recorded in the registers of St. George's, Bloomsbury, a few days afterwards, but it is probable that he was interred in the parochial cemetery near the Foundling Hospital. There is a portrait of him in the board room at the museum presented by his executor. It was probably painted by Benjamin Wilson, with whom he was on terms of intimacy, but it is not the original of the small etching in the Rembrandt manner bearing the inscription, ‘Painted and etched by B. Wilson, 1751,’ which is well known to collectors.

Although the bent of Knight's genius was decidedly experimental and practical, he published a speculative treatise in 1748 entitled ‘An Attempt to demonstrate that all the Phenomena in Nature may be explained by two simple active principles, Attraction and Repulsion, wherein the attractions of Cohesion, Gravity, and Magnetism are more particularly explained.’ The book consists of ninety-one propositions, and is of interest as showing marks of an epoch in which attempts were made to push the Newtonian doctrine into molecular speculations. It preceded Boscovich's better-known work on a similar subject by ten years. Knight also wrote a paper on the earthquake of 8 Feb. 1749–50 (Phil. Trans. xlvi. 603) and some remarks on W. Mountaine's letter on the effects of lightning (ib. li. 294). He was the inventor of ‘dwarf venetian blinds,’ which have since been largely used. He obtained a patent for the invention in 1760 (No. 750).

[Authorities cited; Foster's Alumni Oxonienses; Bloxam's Registers of Magdalen College, vi. 241; Nichols's Literary Illustrations, viii. 626; Nichols's Literary Anecdotes, v. 534; Athenæum, 6 Jan. 1849 pp. 5, 6, 15 Oct. 1849 p. 495; De Morgan in Notes and Queries, 2nd ser. x. 281.]

R. B. P.