First Brigade, Cavalry Division.
Major Charles J. Whiting, 2nd U.S. Cavalry,
5th and 6th United States Cavalry.
(September 17, 1862.)
The Fifth United States Cavalry, Captain Joseph H. McArthur commanding, crossed the middle bridge over the Antietam shortly before noon and took position on the right of the road, its left resting at this point, in support to the Artillery in its front. It was withdrawn across the creek late in the day.
The Sixth United States Cavalry, Capitan William P. Sanders commanding, was detached and deployed in skirmishing order, as a Provost Guard, in rear of the right wing of the Army of the Potomac.