David Rittenhouse (1732-1796) was a mathematician, surveyor, instrument maker, and one of America's premier scientists. Born in Germantown, Pennsylvania, he was largely self-taught and as an instrument maker, he constructed two orreries for Princeton and the University of Pennsylvania. He was a leader in the observance of Venus and Mercury in 1769, and worked on magnetism and electricity. For his work, he was elected as a member of the American Philosophical Society in 1768 (serving as its president from 1791 to 1796). By 1774, he was the city surveyor of Philadelphia. During the American Revolution, he used his skills in military engineering. In the late 1770s, Rittenhouse was a member of the Pennsylvania Assembly, the Pennsylvania Constitutional Convention of 1776, and the Board of War. As a surveyor, he worked on the Pennsylvania boundary with Delaware and western Pennsylvania, and extending the Mason Dixon Line through Ohio.
Rittenhouse and Thomas Jefferson shared the same interest in science and the two became friends. In one exchange in 1790, Jefferson called on Rittenhouse as a friend to help him on his project for uniform weights, measures, and coins. Jefferson would be instrumental in creating a U.S. mint and Rittenhouse would become the first Director of it (1792-1795).
Over the years, Jefferson purchased instruments such as his orrery and odometer from Rittenhouse.
1781. (Notes on the State of Virginia). "We have supposed Mr. Rittenhouse second to no astronomer living: that in genius he must be the first, because he is self-taught. As an artist he has exhibited as great a proof of mechanical genius as the world has ever produced."