Item 006 - Letter from Benjamin Thompson, 18 January 1786

Benjamin Thompson was a physicist and soldier born in Massachusetts on 26 March 1753, though he was a British citizen. In 1772, he married Sarah Walker, and they had a daughter together. Thompson served in the British forces during the American Revolutionary War, including a year working as a spy in New Hampshire. Forced to flee in 1776, he left his wife behind and did not reconnect with her. He was knighted for his service by George III in 1784. He then entered the Bavarian civil service, where he introduced a number of reforms and innovations, including the reorganization of the Bavarian Army, and the use of the steam engine and of the potato as a staple food. In 1791, he was made Count Rumford of the Holy Roman Empire. After returning to England in 1798, he worked with Sir Joseph Banks to establish the Royal Institution of Great Britain. He continued his research and made important discoveries and inventions related to heat, light, and applications for gunpowder. In 1804, his first wife having died in 1792, he married Marie-Anne Lavoisier, though they separated in 1807. He settled in Paris, where he died on 21 August 1814.