[1] After graduating from Shelby College in Kentucky in 1845, he was appointed professor of mathematics and astronomy at that institution.

From 1852 until 1857 he worked as a computer for the American Ephemeris and Nautical Almanac, and relocated to Cambridge, Massachusetts.

He briefly served as head of the department of mathematics at the United States Naval Academy, but returned as superintendent of the Almanac office.

[4] Three year later in 1866 he became director of the Harvard College Observatory, succeeding George Bond, and making many improvements in the facility.

[1] Much of his astronomical work included measurements with the meridian circle, a catalogue of double stars and stellar photometry investigations.