Sadi Carnot (1796-1832)

Sadi Carnot was a French physicist who developed the theory of heat engines and is considered to be the founder of thermodynamics.

Carnot was born during a period of revolutionary unrest and turmoil in France. His father was a highly influential politician and war minister who also made advancements in mechanics and engineering. Carnot’s early education in languages, music, mathematics and science came directly from his father. At the age of 16, Carnot entered the prestigious École Polytechnique in Paris, where his interest in science flourished. On graduating, Carnot embarked on an unsettled military career, during which he was moved from place to place and given jobs of inspecting fortifications, drawing up plans and other administrative duties.

On return to Paris, Carnot became interested in industrial problems and the theory of gases. In particular he was fascinated by steam engines and began to formulate a mathematical theory of heat. Underlying Carnot’s interest in heat, energy and power was a profound nationalistic concern that British steam engines were progressing beyond their French equivalents. When he was only 28 years old, Carnot published his theory of heat engines as a popular book entitled Réflexions sur la puissance motrice du feu (Reflections on the Motive Power of Fire). This book contains a number of key principles including the Carnot cycle, a theoretical proposition which can be thought of as the most efficient heat engine cycle allowed by physical laws. The Carnot cycle lays the foundation for the second law of thermodynamics.

Carnot died in a cholera epidemic in 1832, aged just 36.