Sadi Carnot and the Steam Engine Engineers

Introduction IN the year 1824, in Paris, Nicholas Leonard Sadi Carnot published his Reflections on the Motive Power of Heat' which was destined to lay the foundations of thermodynamics and to distinguish him as one of the very great scientific geniuses. Although he was an engineer2 and wrote primarily for engineers, his work was almost completely neglected by them. A quarter of a century later it was exhumed by two physicists, Kelvin and Clausius,3 and then only slowly diffused into engineering theory and practice. The reason for this indifference towards Carnot's work, especially on the part of the steam engine engineers, is either avoided by historians of science or is meshed with some sweeping generalization such as "he was before his time."' S. Lilley5 and L. Rosenfeld' have suggested that the physicists failed to develop Carnot's ideas immediately because they belonged to a different social world from the engineers, had different perspectives and were thus interested in different kinds of problems. However, there is no comment on why the steam engine engineers, who were vitally concerned with the same problems as Carnot, ignored him. The thesis of this essay is that by the usual