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MOTIVE POWER OF HEAT.
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searching investigation before they ought to be admitted, as they usually have been, by almost every one who has been engaged on the subject, whether in combining the results of experimental research, or in general theoretical investigations.
8. The extremely important discoveries recently made by Mr. Joule of Manchester, that heat is evolved in every part of a closed electric conductor, moving in the neighborhood of a magnet,[1]
- ↑ The evolution of heat in a fixed conductor, through
which a galvanic current is sent from any source whatever, has long been known to the scientific world; but it was pointed out by Mr. Joule that we cannot infer from any previously-published experimental researches, the actual generation of heat when the current originates in electro-magnetic
induction; since the question occurs, is the heat which is evolved in one part of the closed conductor merely transferred from those parts which are subject to the inducing influence? Mr. Joule, after a most careful experimental investigation with reference to this question, finds that it must be answered in the negative. (See a paper "On the Calorific Effects of Magneto-Electricity, and on the Mechanical Value of Heat; by J. P. Joule, Esq." Read before the British Association at Cork in 1843, and subsequently communicated by the Author to the Philosophical Magazine, vol. xxiii., pp. 263, 347, 435.)
Before we can finally conclude that heat is absolutely generated in such operations, it would be necessary to prove that the inducing magnet does not become lower in
