A manual of electro-metallurgy / By George Shaw.

  • Shaw, George
Date:
1844
Catalogue details

Licence: Public Domain Mark

Credit: A manual of electro-metallurgy / By George Shaw. Source: Wellcome Collection.

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    power produced by the contact of small slips of different metals with solutions of the common metallic salts. Opera- ting in this manner, I could readily detect very minute quan- tities of different metals, coat platina with gold, silver, copper, &c., or cover gold with a surface of these metals, and tin, copper, brass, iron, &c.” ..... ** Circumstances which it is unnecessary to mention have hitherto prevented me giving greater publicity to these facts. ..... The fear of trespass- ing too much on the time of the Society, induces me to limit the present paper to one part only of the subject. At no distant period I promise myself the pleasure of communicating the remaining part, which will embrace the different electro- chemical experiments I have made on the other metals and their compounds, together with the application of the facts to the processes of gilding, silvering, tinning, &c.” 10. These experiments of Brugnatelli and Davy having been completely lost sight of, do not affect the merit of suc- ceeding experimenters; and the art cannot be said to have originated until after the origin of the constant battery. 11. It has already been remarked (2), that in Daniell’s battery, metallic copper is precipitated on the copper cylinder containing the solution of the sulphate of that metal. This precipitated copper is not very intimately attached, for, by the application of a very moderate force, it may be torn off. This fact was known to Mr. Daniell, who shewed that the detached metal had been deposited in such close contact with the matrix, that it exhibited impressions of marks on the latter with extreme fidelity; he did not think, however, of applying this fact to any useful purpose. In the course of experiments made with this battery, other philosophers observed the same fact. 12. Mr. Warren de la Rue makes the following remarks in a paper “ On the Effects of a Battery charged with Sulphate of Copper,” published in the London and Edinburgh Philoso- phical Magazine for 1836. “The zinc plate is always par-
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