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.
Longitude east from Washington, D.C.; latitude north from the equator. Also gives time differential for longitudes.
Boundaries of states and some postal routes in color.
First edition was issued in 1866.
"The service on this diagram brought up to date of Spt. 1st 1872."
Includes a table of distances and a table of general statistics for 1860 and 1866.
Railroad routes shown.
Drawn by P. Goepel and engraved by D. McClelland.