designed and constructed under the orders of Postmaster General Wm. Dennison and Second Ass't Postmaster Gen'l Geo. Wm. McLellan, by W.L. Nicholson topographer of P.O. Dept. ; draughtsman P. Goepel ; eng. by D. McClelland.
Prime meridian: Washington, D.C.
Includes a table of distances and a table of general statistics.
Shows towns and major roads with emphasis on railroads.
"The service on this diagram brought up to date of March 1st. 1868." Decr. 29th. 1866 printed below and crossed out.