Page:Popular Science Monthly Volume 62.djvu/133

This page has been proofread, but needs to be validated.

late the mechanical equivalent and to plan the very experiments since carried out by later workers. To give emphasis to this statement, we have but to consider the following translation of his own words:

Heat is nothing else than motive power, or rather, motion which has changed its form. It is a movement of the particles of a body. Wherever there is a destruction of motive power, there is at the same time the production of a quantity of heat precisely proportional to the quantity of motive power destroyed. Reciprocally, wherever there is destruction of heat, there is the production of motive power. We can lay down the general proposition that motive power is a quantity

PSM V62 D133 Carnot notes on the transformation of heat to motive power.png

Facsimile of a Page of Carnot's Note-book Relative to the Transformation of Heat into Motive Power, containing a valuation (the first known to be made) of the so called "mechanical equivalent of heat." This estimate gives for the mechanical equivalent of heat 370 kilogram-meters, which is nearer the correct value (420, Rowland) than Mayer's later determination (365).