Count Rumford (1753-1814), born Benjamin Thompson, English-American physicist and reformer. Born in Massachusetts, he joined the army at 18, acting as a secret agent for the British. He fled to England in 1776 and studied projectiles. He was elected to the Royal Society in 1779. After a brief return to America, he was knighted, and appointed adviser to the Elector of Bavaria. there he reformed the army, set up welfare schemes for the poor, bred stronger horses and cattle and laid out the English Garden in Munich. He also showed, by studying the boring of cannons, that heat was due to the motion of particles in a body.