A Path from Watt’s Engine to the Principle of Heat Transfer

Abstract

1.1 In 1824, Nicolas Léonard Sadi Carnot published a little book, Réflexions sur la Puissance Motrice du Feu et sur les Machines propres a développer celle Puissance, devoted to the study of heat engines. The book was read at the meeting of june 14, 1824, of the Académie Royale des Sciences. The meeting was attended by the best of the contemporary French Science, such as Arago, Fourier, Laplace, Ampère, Gay-Lussac, Poinsot, Fresnel, Legendre, Poisson, Cauchy, Dulong, Navier, Riche De Prony (Eric Mendoza, 1959). However, the book had to await ten years before it was read by Emile Clapeyron and another ten years elapsed before William Thomson came across Clapeyron’s treatment of Carnot’s ideas. Martin J. Klein (1974) showed how influential Carrot’s ideas were to William Thomson and how Rudolf Julius Emmanuel Clausius, motivated by the endless questioning of Thomson, laid the foundations of the theory of thermodynamics, as a synthesis of the law of conservation of energy with a principle first formulated by Carnot. It is true that the latter was modified in a slight, yet profound way by Clausius; however, it is no less true that Sadi Carnot “conceived the very categories of thermodynamic reasoning” (Charles C. Gillispie, 1960, p.367). Among them, Carnot’s principle states that the operation of heat engines consists of a transportation of heat (caloric) from a hot source (the boiler of steam engines) to a cold source (the condenser of steam engines) and not of a consumption of heat (caloric).