David Rittenhouse (1732-1796), US astronomer, inventor, surveyor and public official. Rittenhouse, who was self-taught, started a scientific instrument workshop at the age of 19, building orreries (models of the solar system). He was later among the first to build telescopes in the USA, and made several pioneering observations, including the 1769 transit of Venus. He studied philosophy, and was president of the American Philosophical Society from 1790 to 1796. He was also the first director of the United States Mint. This image, from volume 4 (1896) of the US magazine Popular Astronomy, is a photograph of a portrait showing Rittenhouse at age 40.