The Second Cavalry at dress parade at Carlisle Barracks

This picture of guard-mounting is one of the earliest Civil War cavalry photographs.  It was taken in 1861 at the Cavalry School of Practice and Recruiting Depot, at Carlisle barracks, Pennsylvania.  The guard wears full-dress uniform.  The adjutant is presenting it to the new Officer of the Day, on the right.

(U.S. Army Military History Institute, Carlisle Barracks, PA)