Apr. 4, 1809 Salem Essex County Massachusetts, USA
Oct. 6, 1880 Cambridge Middlesex County Massachusetts, USA
Graduated from Harvard; joined the faculty at Harvard teaching mathematics and astronomy.He was a founder of the Harvard Observatory, one of five planners and organizers of the Smithsonian Institution. He was author of mumerous mathematical works. He married Sarah Hunt Mills, daughter of a congressman and a senator. There were 5 children.