Army blacksmith and forge, Antietam, Md

Dismounted parade of the 7th New York Cavalry in camp, 1862. Some mounted troops are in the background

Federal cavalry column along the Rappahannock
River, Va., 1862

Allan Pinkerton, chief of McClellan's secret service, with his men near Cumberland Landing, Va., May 14, 1862. (Pinkerton is smoking a pipe.)

Scouts and guides for the Army of the Potomac, Berlin, Md., October 1862

Constructing telegraph lines, April 1864