# Dictionary of National Biography, 1901 supplement/Clark, Latimer

​CLARK, LATIMER (1822–1898), whose full name was Josiah Latimer Clark, engineer, was born at Great Marlow, Buckinghamshire, on 10 March 1822.
His elder brother, Edwin Clark (1814–1894), after acting as mathematical master at Brook Green, and then as a surveyor in the west of England, came to London in 1846 and formed the acquaintance of Robert Stephenson [q. v.] (see Times, 26 Oct. 1894). Stephenson appointed him superintending engineer of the Menai Straits bridge, which was opened on 5 March 1850, and in that year Clark published 'The Britannia and Conway Tubular Bridges' (2 vols. 8vo; an atlas formed a third volume). In August 1850 he became engineer to the Electric and International Telegraph Company, and three months later he took out his first patent (12 Nov.) for 'electric telegraphs and apparatus connected therewith.' From that time he divided his time between electric and hydraulic engineering. On 4 Feb. 1856 he took out a patent for 'suspending insulated electric telegraph wires,' but most of his patents (e.g. 19 Jan. 1857, 19 Sept. 1865, 6 May 1870, 9 Jan. 1872, and 18 Feb. 1873) were for improvements in dry docks and floating docks, in the methods of lifting ships out of the water for repairs, and for constructing piers. He was elected a member of the Institution of Civil Engineers on 3 Dec. 1850, was awarded a Telford medal in 1866 for his paper 'On the Hydraulic Lift Graving Dock,' and a Watt medal in 1868 for his papers on 'The Durability of Materials' (Proc. Inst, Civil Engineers, x. 57, xxvi. 121, 138, xxviii. 161, 178). He contributed numerous papers to the 'Proceedings of the Institute of Civil Engineers,' and in 1878 published 'A Visit to South America' (London, 8vo). He died at Cromwell House, Marlow, on 22 Oct. 1894 (Times, 24 Oct. 1894).
Latimer Clark began life as a chemist and spent some years with a firm of chemical manufacturers at Dublin; but in 1847 he commenced railway surveying, and in 1848 was appointed assistant engineer under his brother to the Menai Straits bridge. He helped his brother in preparing his book on that bridge and contributed to it an account of the tides in the Menai Straits. In August 1850 he became assistant engineer under his brother to the Electric and International Telegraph Company. Some ten years later he succeeded his brother as chief engineer to the company, and held this post until the various telegraphic systems were taken over by the government in 1870. Clark introduced several improvements in the telegraph system, notably by coating the gutta percha enclosing underground wires with a solution which prevented its decay; he also invented the insulator known as the 'double-cap invert,' and the battery now known as the Clark cell (Phil. Trans. 1874, p. 1; American Journal of Science, cxxxviii. 402; Preece and Sivewright, Electric Telegraphy, 1899, pp. 41, 433). He took out many patents for these inventions the first on 29 Nov. 1856, four in 1858, and others in 1859, 19 Nov. 1866, 30 June 1870, and 14 Sept. 1871. In 1853 he proved that the rate of the electric current is constant and irrespective of pressure; his experiments were repeated before Faraday (Faraday, Experimental Researches, pp. 508-17), and in 1855 Clark published his results in a pamphlet on 'Experimental Investigation of the Laws which govern the Propagation of the Electric Current in Submarine Telegraph Cables.' On 13 April 1858 he became an associate, and on 19 Nov. 1861 a member, of the Institution of Civil Engineers; he was for some months engineer to the Atlantic Cable Company, and in 1860 served on the committee appointed by government to inquire into the subject of submarine telegraphy.
In 1861 Clark entered into partnership with Sir Charles Tilston Bright [q. v. Suppl.], and their joint paper read at the Manchester meeting of the British Association in that year 'On the Formation of Standards of Electrical Quantity and Resistance' (British Assoc. Reports, vol. xxxi. pt. ii. p. 37) led to the appointment of the committee which fixed the standards now in use. With Bright he invented in 1862 the method of covering submarine cables with asphalt, hemp, and silica, known as Bright & Clark's compound, and for eight years the ​firm was engaged in laying telegraph cables, principally in the east. On 25 Sept. 1868 Bright & Clark dissolved partnership, and Clark formed with Henry Charles Forde (1827–1897) the firm still known as Clark, Forde, & Taylor, of Great Winchester Street, E.G. This firm, mainly under Clark's direction, laid the triplicate cables between Suez, Aden, and Bombay, the duplicate cables between Madras and Penang, and between Singapore and Batavia. The firm also laid cables between Singapore and Nagasaki; England, Gibraltar, Malta, and the Levant; Durban and Delagoa Bay; five Atlantic cables beginning with that between Brest and Newfoundland in 1869; and the first South Atlantic cable from Pernambuco to St. Louis in Senegal.
Clark was also interested in other forms of engineering. His earliest patent (28 Jan. 1854) had been one for 'conveying letters or parcels between places by the pressure of air and vacuum.' A similar patent was taken out on 11 June 1857, and subsequently he constructed the 4 ft. 6 in. pneumatic tube between the General Post Office and Euston station. In 1874 he entered into partnership with John Standfield as an hydraulic and canal engineer; the works of the firm were at Grays, Essex, and it constructed numerous floating docks, notably those at Vladivostock, Hamburg, Havana, Stettin, and North Shields. He was also senior partner in the firm of Latimer Clark, Muirhead, & Co., formed in 1875 to manufacture electrical apparatus and machinery.
In 1870–1 Clark took a large part in founding the Society of Telegraph Engineers and Electricians (now the Institution of Electrical Engineers), and in 1874–5 he served as its fourth president. On 6 June 1889 he was elected F.R.S., and he was also fellow of the Royal Astronomical and Geographical Societies. To astronomy and photography he devoted much of his leisure; he assisted Sir George Biddell Airy [q. v. Suppl.] in 1857 to devise a method of indicating Greenwich mean time throughout the country, and in 1853 he invented a camera for taking stereoscopic pictures with a single lens (Journal of Photographic Soc. 21 May 1853).
Clark died, aged 76, on 30 Oct. 1898 at his residence, 31 The Grove, Boltons, S.W., and was buried at the Kensington parochial cemetery, near Hanwell. He was twice married and left issue. A portrait of him is reproduced in Bright's 'Life of Sir C. T. Bright' (ii. 19).
Besides numerous papers contributed to the 'Proceedings of the Institution of Civil Engineers' and to other scientific periodicals, of which a list is given in the 'Royal Society's Catalogue,' Clark was author of the following independent works: 1. 'An Elementary Treatise on Electrical Measurement,' 1868, 8vo; translated into French (Paris, 1872) and into Italian (Genoa, 1874). 2. (with Robert Sabine) 'Electrical Tables and Formulæ,' 1871, 8vo. 3. 'A Treatise on the Transit Instrument,' 1882, 8vo (reissued 1884 as 'A Manual of the Transit Instrument'). 4. (with Herbert Sadler) 'The Star Guide,' 1886, 8vo. 5. 'Dictionary of Metric and other useful Measures,' 1891, 8vo. 6. 'Memoir of Sir William Fothergill Cooke' [q. v.], 1895.
[Proc. Inst. Civil Engineers, cxxxvii. 418-23; Journal Instit. Electrical Engineers, 1898 pp. 646–7, 1899 pp. 666–72; Times, 1 Nov. 1898; Men of the Time, ed. 1891; Who's Who, 1898 (Suppl.); Smiles's Lives of the Engineers, iii. 428, 431, 437; Celebrities of the Day, 1881 (notice by J. T. Humphreys issued separately same year); Lists of the Royal Society; Ronalds's Cat, of Scientific Papers; Fleming Jenkin's Scientific Papers, ii. 207–8, 230, 237; Index of Patentees, 1852–88; E. B. Bright's Life of Sir C. T. Bright, 1899; Charles Bright's Submarine Telegraphy, 1898.]
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