III. On the mechanical equivalent of heat

Abstract “Heat is a very brisk agitation of the insensible parts of the object, which produces in us that sensation from whence we denominate the object hot; so what in our sensation is heat, in the object is nothing but motion.”—Locke. “The force of a moving body is proportional to the square of its velocity, or to the height to which it would rise against gravity.”— Leibnitz.