Rumford, Benjamin Thompson, Count Rumford (1753-1814)

American-born British physicist and inventor. In 1798, impressed by the seemingly inexhaustible amounts of heat generated in the boring of a cannon, he published his theory that heat is a mode of vibratory motion, not a substance. Rumford spied for the British in the American Revolution, and was forced to flee from America to England 1776. He travelled in Europe, and was created a count of the Holy Roman Empire for services to the elector of Bavaria 1791. Rumford devised the domestic range - the 'fire in a box' - and fireplaces incorporating all the features now considered essential in open fires and chimneys, such as the smoke shelf and damper. Rumford was born in Massachusetts and was self-educated. In Bavaria he became war and police minister as well as grand chamberlain to the elector. He cofounded the Royal Institution in London 1799, and two years later moved to France. In Bavaria, Rumford employed beggars from the streets to manufacture military uniforms, and took responsibility for feeding them. A study of nutrition led him to devise many recipes, emphasizing vegetable soup and potatoes. Meanwhile soldiers were being employed in gardening to produce the vegetables. His search for an alternative to alcoholic drinks led to the promotion of coffee and the design of the first percolator. He invented the Rumford shadow photometer and established the standard candle, which was the international unit of luminous intensity until 1940. He also devised a calorimeter to compare the heats of combustion of various fuels. Rumford even planned the large park in Munich called the Englischer Garten.