Andrew Ellicott

A surveyor and mathematician, Ellicott published 'The United State Almanack' in New Jersey (1782). He surveyed the western boundaries of Pennsylvania and New York and worked on the western extension of the Mason-Dixon line. In 1791-93 he surveyed the site of the District of Columbia; the design of the city was L'Enfant's, but Ellicott marked off many of the sites laid out in the design. After L'Enfant's dismissal he re-drew the plan for the engraver, incorporating certain alterations that were supplied by President Thomas Jefferson (q.v.). This became known as the Ellicott Plan. From 1796 to 1800 he plotted the border between Florida and the United States and in 1811 surveyed the boundary between Goergia and South Carolina. From 1813 until his death he taught mathematics at the U.S. Military Academy at West Point.