Reconnaissance Map from the Battle of Antietam, 1862
Battle of the Antietam fought September 16 & 17, 1862. Reconnaissance of the ground occupied by the 1st Army Corps commanded by Maj. Gen. Hooker. Made under the direction of Maj. D. C. Houston, Chf. Engr., by Lieut. W. A. Roebling and W. S. Long, C.E.