Crystal Palace International Electric Exhibition 1881-82

75 256 .—L. Clark, Muirhead & Co., 23, Regency Street, West- minster. Muirhead's Improved Form of Thomson and Varley^ Slide-resistance Coils, Registered Design; Standard Condenser, | Microfarad; Standard Condenser, | Microfarad; Standard Condenser, 1 Microfarad j Standard Condenser, 1 Microfarad, subdivided -1 ’2 '3 ’4=1, Microfarad. {See Advt. p. 131.) Between Sheffield Court and Chinese Court. 257 .—Elkington & Co., Manufacturing Silversmiths, 22, Regent Street, S.W., London. Inventors of the electro-plating pi-ocesses and fine art reproducers in the precious and other metals; bronzists, &c. Exhibit specimens of objects produced entirely by electro deposition. Articles gilt and silvered by the electro processes; electrotype, bronzes, bas-reliefs, &c., &c. Candelabra, lamps, chandeliers, sconces, &c., fitted with Swan’s Incandescent Lights, adapted for the lighting of drawing-rooms, dining-rooms, and other domestic purposes. The various processes of Electro-depositing, Gilding, Plating, Moulding, &c., shown in operation, and explained by skilled operators. West Corridor. 258 .—Wm. Elmore, 91, Blackfriars Road, S.E. The “Elmore” Dynamo-Electric Machine, and special electro-depositing solutions for depositing Gold, Silver, Copper, Brass, Tin, Zinc, and Nickel, in Electro-plating. The cc ElmoreDynamo-Electric Machines Electrotyping, Manufacturing Tin-plates, Galvanizing, Refining Metals, Extracting Metals from their Ores, Generating Oxygen, Hydrogen, and other gases. Chemicals used in the art processes Electrotypes, Art Subjects, Bank-note Plates, etc., which have been produced by the <c Elmore” machine. Metal goods of various kinds which, have been electro-plated by the “ Elmore ” machine. {See Advt. pp. 110 & 111.) Avenue between Pompeian House and Chinese Court. 259 .—Db. J. H. Gladstone and Mr. A. Tribe, 1 7, Pembridge Square. Applications of Local Electric Action to Chemical' WorJc The chief agent employed is named the copper-zinc couple. It consists of zinc coated with spongy copper, or zinc mechanically associated by heat with the negative metal. The principal results of its application are: (a) The decomposition of water (exhibited); (6) Preparation of the paraffins, or the hydrides, of the alcohol radicals (exhibited); (c) Preparation of many zinc ethers; {d) Reduction of nitrates and nitro-compounds (exhibited); (e) Information concerning the constitution of many organic com- pounds. Another couple is lead coated with spongy peroxide, as in the Plante and Faure accumulators. The results exhibited are: (a) The decomposition of water, with formation o£ the yellow oxide; (6) The decomposition of dilute sulphuric acid, with formation, of sulphate of lead. South Nave. 260 . Alfred Tribe, F.I.C. (Lecturer on Chemistry in Dulwich College) 14, Denbigh Road. Electrographs: Silver plates on which are deposited copper and silver peroxide. These deposits are obtained while the insulated plate stands immersed in a d 2