Benoît Paul Émile Clapeyron

Benoît Paul Émile Clapeyron was born on 26 January 1799, trained as an engineer in France, and spent his career translating the messy, practical problems of heat and steam into the clean language of mathematics. He became one of the founders of thermodynamics, the science governing energy transformation. His work gave structure to ideas about how heat moves, how substances change state, and how machines extract power from temperature differences. He died on 28 January 1864, two days after his sixty-fifth birthday, leaving behind equations still taught to engineers learning why pressure and temperature lock together the way they do.