A new theory of galvanism : supported by some experiments and observations made by means of the calorimotor, a new galvanic instrument ; also, a new mode of decomposing potash extemporaneously ; read before the Academy of Natural Sciences, Philadelphia / by Robert Hare, M.D. ; ... accompanied by an engraving.

  • Hare, Robert, 1781-1858.
Date:
1819
Catalogue details

Licence: Public Domain Mark

Credit: A new theory of galvanism : supported by some experiments and observations made by means of the calorimotor, a new galvanic instrument ; also, a new mode of decomposing potash extemporaneously ; read before the Academy of Natural Sciences, Philadelphia / by Robert Hare, M.D. ; ... accompanied by an engraving. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    a Voltaic apparatus, that he considers it an objection to the materiality of heat; since the wire could not be imagined to contain sufficient caloric to keep up the emission of this principle for an unlimited time. But if we conceive an accumulation of heat to accom- pany that of electricity throughout the series; and to be propagated from one end to the other, the explana- tion of the phenomenon in question is attended by no difficulty. The effect of the Galvanic fluid on charcoal is very consistent with my views, since, next to metals, it is one of the best conductors of electricity, and the worst of heat, and would therefore arrest the last and allow the other to pass on. Though peculiarly liable to intense ignition when exposed between the poles of the Voltaic apparatus, it seems to me it does not display this characteristic with common electricity. According to Sir Humphey Davy, when in connec- tion with the positive pole, and communicating by a platina wire with the negative pole, the latter is less heated than when, with respect to the Doles, the situa- tion of the wire and charcoal is reversed. The ratio- nale is obvious : charcoal, being a bad conductor, and a good radiator, prevents the greater part of the heat from reaching the platina, when placed between it and the source whence the heat flows. I had observed that as the number of pairs in Vol- ta's pile had been extended, and their size and the energy of interposed agents lessened, the ratio of the electrical effects to those of heat had increased ; till in