On 24 May 1820 a manuscript entitled ‘A Mathematical Inquiry into the Causes, Laws and Principal Phenomena of Heat, Gases, Gravitation, etc.’ was submitted to Davies Gilbert for publication in the
Philosophical Transactions of the Royal Society
. The author was John Herapath (1790-1868), and his article included a comprehensive (if somewhat faulty) exposition of the kinetic theory of gases. Sir Humphry Davy, who assumed the Presidency of the Royal Society on 30 November 1820, became primarily responsible for the fate of the article and wrote several letters to Herapath concerning it. After it became clear that there was considerable opposition to its publication by the Royal Society, Herapath withdrew the article and sent it instead to the
Annals of Philosophy
, where it appeared in 1821 (1). Herapath’s theory received little notice from scientists until thirty-five years later, when the kinetic theory was revived by Joule, Krönig, Clausius, and Maxwell. The incident is significant in the history of physical science because it illustrates an important distinction between the two doctrines concerning the nature of heat—the kinetic and the vibration theories—a distinction which is often forgotten because of the apparent similarity of both doctrines as contrasted with the caloric theory. It also throws some light on the character of early nineteenth century British science, both in and out of the Royal Society.