Volume 1

A system of chemistry / by John Murray.

  • Murray, J. (John), -1820.
Date:
1819
Catalogue details

Licence: Public Domain Mark

Credit: A system of chemistry / by John Murray. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    tals it is such as to allow of a galvanic arrangement being formed with a single metal: in this way is explained the construction of such an arrangement, from a metal with its different sides in contact with diluted nitric acid and a so- lution of sulphuret of potash. And if there were solid substances conductors of electricity without havino- the elect: o-motive power, a pile might even be constructed by their medium, without the intervention of fluid. If a greater diflerence, for example, existed between three metals in the electro-motive quality than does exist, an electric column might be formed entirely metallic, and permanent in its o- peration *. The hypothesis opposed to Volta’s, is that w])ich sup- poses the electricity in a galvanic series to be evolved in consequence of the chemical action of the substances com- posing It. It was suggested by the researches of Fabroni with regard to the mutual action of metals. He had ob- served, that metals when pure preserve their lustre for a long time, but that their alloys are quickly tarnished, and oxidated by exposure to the air; that the contact of two metals hastens the oxidation of each ; and hence, as he found, that if pure metals be put in separate vessels of wa ter, they arc not altered ; but if two of them be inimersecl in water in contact, the more oxidable one is soon loaded with oxide. The signs of electricity observed when two metals are separated from contact, were considered as the consequence of this chemical action rather than the cause* all the other phenomena, even the sensations which the metals excite, Fabroni regarded as the immediate effect! of the chemical action, and not the effects of the electrici * Report to the National Institute, translated in the Philo sophical Magazine, vol. xi, p. 301. Letter of Volta, translat- ed m Nicholson’s Journal, 8vo, vol. i, p. 135., and Memoir by Volta, Annales de Chimie, t. xl, p. 225.