James H. Simpson (1813-1883) & James W. Abert (1820-1897)
Part of Loudon County, Virginia. Prepared for Col. Crosman USA Chief of
Quartermasters. Department Dept. of Penn.2. Harpers Ferry July 29 1861
Manuscript map with pen, ink, and wash on silk
Signed by the mapmakers
Sheet size: 18 x 30 in.
Frame size: 27 3/4 x 39 1/2

This map depicts the northern part of Loudoun County, located in a curve of the Potomac on the Maryland border, northwest of Washington. As a border county, it was divided territory. Two of the towns had voted strongly against joining the Confederacy, but not enough to sway the county as a whole.