measuring the mechanical equivalent of heat. Thomson and Tait were angered, and an undignified public exchange of correspondence took place in the pages of the Philosophical Magazine, and the rather more popular Good Words. Tait even resorted to championing Colding's cause in an attempt to undermine von Mayer. Though Tyndall again pressed von Mayer's cause in Heat: A Mode of Motion (1863) with the publication of Sir Henry Enfield Roscoe's Edinburgh Review article Thermo-Dynamics in January 1864, Joule's reputation was sealed while that of von Mayer entered a period of obscurity. Notes References Further reading Foucault, L. (1854) “Equivalent mécanique de la chaleur. M. Mayer, M. Joule. Chaleur spécifique des gaz sous volume constant. M. Victor Regnault”, Journal des débats politiques et littéraires, Thursday 8 June , pp. 154–5 Smith, C. (2004) "Joule, James Prescott (1818-1889)", Oxford Dictionary of National Biography, Oxford University Press, <http://www.oxforddnb.com/view/article/15139, accessed 27 July 2005> (subscription required) Zemansky, M.W. (1968) Heat and Thermodynamics: An Intermediate Textbook, McGraw-Hill, pp. 86–87 External links History of thermodynamics History of physics