Thompson, Benjamin Count Rumford

THOMPSON, BENJAMIN COUNT RUMFORD. (1753–1814). Colonial administrator, physicist, Loyalist. Massachusetts-New Hampshire. Born in Woburn, Massachusetts, on 26 March 1753, Thompson—famous as one of America's leading scientists and a mean-spirited social climber—was self educated, only attending a few lectures at Harvard in 1770. In 1771 he became a schoolteacher in Concord, New Hampshire, where he met and, the following year married, the widow Sarah Walker Rolfe, the largest landholder in the region. They separated in 1775, but Thompson was able to hold on to a great deal of his wife's wealth. Through her, Thompson met Governor John Wentworth, who appointed the twenty-year-old teacher with no military background a major of militia in 1773. Though the Patriots suspected Thompson of favoring the crown as early as 1774, the smooth-talking major persuaded two inquiries of his patriotism. He associated with Patriots in Massachusetts, gaining information about the Continental army encircling Boston and passing on what he learned to General Thomas Gage. In October 1775, suspecting his cover was blown, he joined the British in Boston, sailing from there to England in March 1776. There he became a favorite of Lord George Germain, who appointed him to the sinecure of secretary of Georgia. In September 1780 Thompson became undersecretary of state for the Northern Department, and in October 1781 he returned to America as lieutenant colonel of the King's American Dragoons, seeing some action around Charleston in March 1782 and commanding a regiment on Long Island, in New York, until April 1783.

In August 1783, having returned to England, he was made colonel of the King's American Dragoons and was retired on half pay. He was knighted on 23 February 1784 and for the next eleven years he served the elector of Bavaria as minister of war, minister of police, and grand chamberlain. In addition to reforming the Bavarian army, Thompson conducted important research in these years on the nature of heat and light and introduced the potato to central Europe. In 1791 he was made count of the Holy Roman Empire and chose his title of Rumford from the township of his wife, though he had not seen her since 1775. Thompson returned to England in 1795, inventing the famous Rumford Lamp, a more efficient oil lamp, sometime thereafter. In 1796 he published his Essays, Political, Economical, and Philosophical and gave one thousand pounds to the Royal Society and five thousand dollars to the American Academy of Arts and Sciences to award Rumford Medals for distinguished work on heat or light. He did some of the first research into air pollution and nutrition and developed a nonsmoking and highly efficient fireplace known as the Rumford Roaster that came into extensive use in Great Britain and America.

In 1802 he settled in Paris, where in 1805 he married Marie Anne Pierrette, the widow of the eminent chemist Antoine Lavoisier; they separated four years later. He died at Auteuil on 21 August 1814, leaving funds to create the Rumford professorship of physics at Harvard University.

                              revised by Michael Bellesiles