Nicolas Léonard Sadi Carnot (French pronunciation: [nikɔla leɔnaʁ sadi kaʁno]; 1 June 1796 – 24 August 1832) was a French mechanical engineer in the French Army, military scientist and physicist, often described as the "father of thermodynamics". He published only one book, the Reflections on the Motive Power of Fire (Paris, 1824), in which he expressed the first successful theory of the maximum efficiency of heat engines and laid the foundations of the new discipline: thermodynamics. Carnot's work attracted little attention during his lifetime, but it was later used by Rudolf Clausius and Lord Kelvin to formalize the second law of thermodynamics and define the concept of entropy. Driven by purely technical concerns, such as improving the performance of the steam engine, Sadi Carnot's theoretical work laid important foundations for modern science as well as technologies such as the automobile and jet engine. His father Lazare Carnot was an eminent mathematician, military engineer, and leader of the French Revolutionary Army. Source: Wikipedia (en)