He received his first important public commission in 1771, when he and Ephraim Mitchell were appointed by Governor Lord Charles Grevill Montague to survey the boundaries of the civil districts of South Carolina.
The copy of the Mouzon map carried by George Washington is preserved at the American Geographical Society Library in Milwaukee, Wisconsin.
[4] The copy of the Mouzon map carried by Sir Henry Clinton, the British Commander, is preserved at the William L. Clements Library at the University of Michigan in Ann Arbor.
His five suggested routes were later abandoned Colonel Johann Christian Senf, however, Mouzon played a seminal role in the creation of America's first true canal system.
[6] When Mouzon's oldest daughter Nancy (Ann) died in 1859, at the age of 90, the Kingstree Star published her memory of the firing:[7] The subject of this memoir, then 11 years old, was on the roof of the smoke-house, aiding in spreading the bacon to the sun, and was the first to descry the approach of the enemy and give the alarm.
His daughter well remembered the personal appearance of Col. Tarleton and also of Col. Ball, his Tory ally, and the dress of the British troopers—leather cape with plumes, red coats, white pantaloons and half boots.
The two officers approached Mrs. Mouzon courteously and told her with apparent regret that "Harry," meaning her husband, had turned against the King and must consequently be broken up.
[7]Following the destruction of the Mouzon Plantation on August 7, 1780, the citizens of Williamsburg sent Major James to Georgetown, South Carolina to inquire of the British Commander, Naval Captain Ardesoif, of the conditions of their parole.