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 8905) for the electro-deposition of works of art. He describes himself in his earlier patents as an artist, but subsequently under the more correct designation of ‘chemist.’ The deposition of metals by electricity continued to interest him almost to the end of his life, and upon one occasion, when giving evidence in court, he was referred to as ‘the Nestor of electro-metallurgy.’

Among the ingenious processes which he devised in connection with electro-metallurgy mention may be made of his method of electro-plating flowers and fragile natural objects, which is included in a patent granted in 1843 (No. 9807). The objects are first dipped in a solution of phosphorus in bisulphide of carbon, and subsequently in nitrate of silver. A finely divided coating of silver is precipitated upon the specimen, upon which, when connected with the battery and placed in the proper solution, any quantity of either copper, silver, or gold can be deposited. A bunch of flowers so treated may be seen at the geological museum in Jermyn Street; and, on the occasion of a visit to Messrs. Elkington's works at Birmingham, Prince Albert was presented with a spider's web which had been coated with silver.

Parkes was an exceedingly prolific inventor, and his patents number sixty-six, extending over a period of forty-six years. They relate mostly to metallurgy, and abstracts of all his inventions belonging to this subject are given in a handy form in the ‘Abridgments of Patents relating to Metals and Alloys,’ published by the patent office. He was one of the earliest to suggest the introduction of small quantities of phosphorus into metallic alloys for the purpose of giving additional tenacity to such compounds. In 1841 he patented a process for waterproofing fabrics by the use of a solution of indiarubber in bisulphide of carbon (No. 9807), which was carried out by Elkington & Mason in Birmingham for some years, the patent being eventually sold to Macintosh & Co., and now extensively used all over the world as the ‘cold converting process.’

From 1850 to 1853 he was at Pembrey, South Wales, engaged in superintending the erection of copper-smelting works for Elkington & Mason; and to this period belongs his method of using zinc for the desilverisation of lead, which was first patented in 1850 (No. 13118), and further developed by patents granted in 1851 (No. 13673) and in 1852 (No. 13997). This process was used at Messrs. Sims's works at Llanelly, but was discontinued in 1859. It attracted much attention in Germany, and it is in universal use in America, to the exclusion of the Pattinson process [see ]. It is perhaps one of the most important of Parkes's inventions. The theory and mode of working are fully discussed in Percy's ‘Metallurgy: Lead’ (pp. 148, 171) and in Phillips's ‘Metallurgy’ (3rd ed. p. 694). For an account of the American developments of the process, see Egleston's ‘Metallurgy in the United States’ (i. 63).

In 1858 he began to turn his attention to the manufacture of seamless metal tubes and cylinders for calico-printing. He took out several patents relating to this subject, and the method eventually became of some importance.

The compound of pyroxyline now generally known as xylonite, or celluloid, was invented by Parkes, and formed the subject of a number of patents, commencing in 1855 (No. 235). He showed articles made from this substance, which was named Parkesine, at the exhibition of 1862, when he received a medal. He was also awarded a similar distinction at the Paris exhibition of 1867. Although Parkes made great efforts to produce a material which should serve as a substitute for ivory, he was never able to make the manufacture a commercial success. It was taken up in America, and reintroduced into this country about twelve years ago, the applications of the material being now very numerous. Parkes gave an account of the development of his invention in a paper read before the Society of Arts in 1865 (see Journ. Soc. Arts, xiv. 81).

Parkes left Birmingham about 1881, and went to reside in the neighbourhood of London. He died at West Dulwich on 29 June 1890.

[Obituary notices in Birmingham Daily Post, 5 July 1890, Engineering, 25 July 1890, p. 111, Mining Journal, 26 July 1890 p. 855.] 

PARKES, DAVID (1763–1833), schoolmaster, draughtsman, and antiquary, son of John Parkes, of an old family in reduced circumstances, was born on 21 Feb. 1763, at Cakemore, near Halesowen, Shropshire. Parkes, after being educated in the village school, was apprenticed to a japanner at Birmingham, but soon set up a small school, and eventually obtained a situation as usher in a private school. He meanwhile cultivated a natural love of art, and became proficient in French. Parkes soon removed to Shrewsbury, where he established, in a house called ‘The Franciscan Friars,’ a school for the mercantile classes, which obtained some repute, and subsequently was transferred to larger premises in Castle Street. He spent his leisure in travelling about his native