Mr. John Rid gway, of Cauldon-place, Staffordshire, England, china manufacturer, has recently patented certain improvements in the method or process of ornamenting or decorating articles of glass, china, earthenware, or other ceramic manufactures. In the specification of his patent, just enrolled, Mr. Ridge-way states that his first object is to apply a new glaze, which shall enable the metallic coating to adhere firmly, by capillary attraction, and give affinity far copper as a first coating. In pursuance of this, he first submits the article to an alcoholic solution, or a gela-tinam atfrBfftn;" He'tbentmahe* ovr it an impalpable powder, composed of half carburet of iron, and half sulphate of copper. The article thus treated is then to be corrsded by the fumes of hydro-fluoric acid. The article is then to be smoothed, by brushing it over with silver sand, or by the scratch-brush ; but when the shape and nature of the article will not admit of this, it is to be plunged into a liquor, consisting of 6 quarts sulphuric acid, 4 quarts aquafortis, three-fourth oz. muriatic acid, and 6 quarts water. Grease is to be carefully removed from the article, and a thin film of mercury is to be applied. The solution of copper consists of 1 sulphate of copper, and 4 filtered water. Suitable solutions for silvering or gilding are to be applied, in accordance with the practice of electrotyping. The claim is not to the solutions for coating as such, but to the application of "electrotyping," or electro-metallurgy, to the objects stated in the title, provided the articles be so prepared as to allow them to combine from an alloy with them.
This article was originally published with the title "Electro-Metallurgy Applied to the Ornamentation of Glass, China, &c" in Scientific American 8, 21, 161 (February 1853)