Army of the Potomac

   Early in the morning the 20-Pounder Parrot gun Batteries of Taft, Langer, Von Kleiser and Wever, First New York Artillery, were in position on the ridge east of the Antietam and north of the Boonsboro Pike; Battery E (Benjamin's) 2nd U.S. and Battery I (Weed's) 5th U.S. on the ridge south of the Pike, and all engaged the Confederate Artillery on the heights east and north of Sharpsburg. About 8 A.M. four Companies of the Fourth U.S. Infantry crossed the Antietam by the Middle Bridge, and, late in the day, engaged the Confederate Infantry. About noon Morell's Division, Fifth Corps, arrived from Frederick and encamped near Keedysville. The Ninth Corps moved to the left on the high ground opposite and commanding the lower stone bridge. Between 3 and 4 P.M. Hooker's (First) Corps crossed the Antietam by the Upper Bridge and a ford below it, moved westerly until it reached the high ground near the Hagerstown Pike, then changed direction to the left, moved south, and encountered the Confederate outpost, on and near the Smoketown Road, about one and three-quarters miles north of this point. The advance was continued under Artillery and musket fire until dark, when Hooker went into bivouac, the right of his line on the Hagerstown Pike, at J. Poffenberger's, the left across the Smoketown Road where it entered the East Woods from the north. During the night Mansfield's (Twelfth) Corps crossed the Antietam by the Upper Bridge and bivouacked about a mile in Hooker's rear.