Description
Autograph Letter Signed ‘John Percy’, to E.W.Cooke R.A., responding to an invitation, explaining “I have a volume on hand which I must get published as soon as possible” 2 pp. 7 x 4 inches, fine. House of Commons, 20 October 1873. “I have brought for you a waterproof cloak which you left. I hoped to have brought also a specimen of Asperium Septentrionale.” John Percy (1817–1889), metallurgist. In 1848 he contributed a paper to the Chemist on a mode of extracting silver from its ores (depending on the solubility of the chloride in sodium thiosulphate), which led to the Von Patera process, used at Joachimsthal, and the Russell process, employed in the western states of America. Percy made the first serious attempt at a survey of iron ore deposits in Britain. They were included in the volume Iron and Steel (1864), part of his great Treatise on Metallurgy, of which the first volume was published in 1861.