# Dictionary of National Biography, 1885-1900/Percy, John

​PERCY, JOHN (1817–1889), metallurgist, third son of Henry Percy, a solicitor, was born at Nottingham on 23 March 1817. He went to a private school at Southampton, and then returned to Nottingham, where he attended chemical lectures by a Mr. Grisenthwaite at the local school of medicine. He wished to become a chemist, but yielded to his father's desire that he should graduate in medicine, and in April 1834 was taken by his brother Edmund to Paris to begin his medical studies. While in Paris he attended the lectures of Gay-Lussac and Thénard on chemistry, and of A. de Jussieu on botany. In 1836 he went for a tour in Switzerland and the south of France, and made a large collection of mineralogical and botanical specimens. In the same year he proceeded to Edinburgh, where he became a pupil of Sir Charles Bell [q. v.] and a friend of Edward Forbes [q. v.] In 1838 he graduated M.D. in the university, and obtained a gold medal for a thesis on the presence of alcohol in the brain after poisoning by that substance. In 1839 he was elected physician to the Queen's Hospital, Birmingham, but, having private means, did not practise. The metallurgical works in the neighbourhood excited his interest in metallurgy. In 1846 he worked with David Forbes (1828–1876) [q. v.] and William Hallowes Miller [q. v.] on crystallised slags. In 1847 he became a fellow of the Royal Society, and served on the council from 1857 to 1859. In 1848 he contributed a paper to the ‘Chemist’ (vol. i. p. 248) on a mode of extracting silver from ​its ores (depending on the solubility of the chloride in sodium thiosulphate), which has led to the Von Patera process, used at Joachimsthal, and the Russell process, now largely employed in the western states of America (Roberts-Austen, in Proc. Roy. Soc.) In 1851 he was elected F.G.S., and was appointed lecturer on metallurgy at the newly founded Metropolitan School of Science (later Royal School of Mines, and now Royal College of Science) in London, under Sir Henry Thomas de la Beche [q. v.]; the post was later made a professorship. The influence exerted by Percy, while holding this position, on English metallurgy was of the utmost importance. As he said in his inaugural address, metallurgy was then looked on as an empirical art, and ‘experience without scientific knowledge [was thought] more trustworthy than the like experience with it’ (Roberts-Austen in Nature, xl. 206). Percy was an excellent lecturer and teacher, and most English metallurgists of his time were his pupils. Although the silver process was the only metallurgical one he actually invented, his work suggested many others; and the exceedingly important Thomas-Gilchrist process for making Bessemer steel from iron ores containing phosphorus was an outcome of his work (Percy, Iron and Steel, pp. 815, 818, 819), and was discovered by his pupils. In 1851 he undertook to superintend the analysis of a large number of specimens of iron and steel collected by his friend S. H. Blackwell (and now in the Jermyn Street Museum), and made partly at Blackwell's expense (ib. p. 204). His results constitute ‘the first serious attempt at a survey of our national resources as regards ores of iron.’ They were embodied in the volume on ‘Iron and Steel’ (published in 1864) of his great treatise on metallurgy, the first work of the kind written in modern times. This treatise (1861–80), which remained uncompleted, contains over 3,500 pages of terse and exact description of metallurgical processes, of minute and scientific discussion of the chemical problems they involve, often based on the author's careful original research, and of suggestions for future investigation. The drawings of plants are remarkably exact. The book, which has been translated into French and German, and has become a classic, involved an immense amount of labour. Percy's work on alloys, his discovery of ‘aluminium bronze,’ and his view that in many countries the iron age preceded the bronze age, deserve special mention.
Percy was appointed lecturer on metallurgy to the artillery officers at Woolwich in 1864 (circa) (Journal of the Iron and Steel Institute, 1885, i. 8), and retained this post till his death. He was appointed superintendent of ventilation, &c., of the houses of parliament on 6 Feb. 1865. He was also a member of the secretary for war's commissions on the application of iron for defensive purposes (1861), and on ‘Gibraltar’ shields (1867), and of the royal commissions on coal (1871), and on the spontaneous combustion of coal in ships (1875). In 1876 he was awarded the Bessemer medal of the Iron and Steel Institute, of which he was president during 1885 and 1886. In December 1879 the government decided to complete the removal of the Royal School of Mines from the Museum of Practical Geology in Jermyn Street to South Kensington. Objecting strongly to this course, Percy twice offered to rebuild the metallurgical laboratory in Jermyn Street; but his offer was refused, and he thereupon, in December 1879, resigned (Percy's letter to the Times, 1 Jan. 1880). Percy circulated a pamphlet containing his views on the subject (Journal of the Iron and Steel Institute, 1889, i. 210). In 1887 he was awarded the Millar prize of the Institute of Civil Engineers. In 1889 he received the Albert medal of the Society of Arts on his deathbed, with the words, ‘My work is done.’ He died on 19 June 1889. He had married, in 1839, Grace, daughter of John Piercy of Warley Hall, Birmingham; she died in 1880.
Percy was very tall and spare, and had strongly marked features. Shy in his early years, he became fond of society later, and received many friends at his home, first in Craven Hill, and afterwards in Gloucester Crescent, Bayswater. He frequented the Athenæum and Garrick Clubs, and was of a genial, though at times brusque, temper. He took an interest in social and political questions, on which he wrote many trenchant letters to the ‘Times’ under the signature ‘Y;’ and he could not refrain from denouncing the home-rule movement in his presidential address to the Iron and Steel Institute in 1886. A fair artist himself, he made a valuable collection of water-colour drawings and engravings, which were dispersed by sale in 1890. The manuscript catalogue of the water-colour drawings was bought by the British Museum. Percy's collection of metallurgical specimens is now at South Kensington.
Percy's publications are: 1. ‘Experiments [on] the Presence of Alcohol in the Ventricles of the Brain after Poisoning by that Liquid’ [1839]. 2. ‘On the Importance of Special Scientific Knowledge to the Practical Metallurgist’ (government publication), ​1852. 3. ‘On the Metallurgical Treatment and Assaying of Gold Ores,’ 1852; 2nd edition, 1853. 4. ‘A Treatise on Metallurgy,’ including vol. i. ‘On Fuel, Copper, Zinc, and Brass;’ vol. ii. ‘On Iron and Steel,’ 1864, 2nd edition 1875; vol. iii. ‘On Lead,’ 1870; and vol. iv. ‘On Silver and Gold,’ 1880. 5. ‘On the Manufacture of Russian Sheet-Iron,’ 1871. The Royal Society's ‘Catalogue’ (vols. iv. viii. and x.) contains a list of twenty-one papers published by Percy singly, one in conjunction with W. H. Miller, and one with R. Smith. Besides these he published two presidential addresses to the Iron and Steel Institute in their ‘Journal’ (1885, i. 8, and 1886, i. 29), and an article ‘On Steel Wire of High Tenacity’ (ib. 1886, i. 162).
P. J. H.