September 4, crossed the Potomac at Georgetown, and moved to near Tennallytown, and encamped.
September 5, the division move to near Rockville, Md., and escaped.
September 6, moved a short distance, formed in line of battle, and lay upon the field.
September 7, lay upon the field.
September 8, the One hundred and twenty-fourth, One hundred and twenty-fifth, and One hundred and twenty-eighth Regiments Pennsylvania Volunteers assigned to First Brigade.
September 9, moved to Middlebrook and bivouacked.
September 10, moved to Damascus, Md.
September 11, remained in camp.
September 12, moved to near Ijamsville and bivouacked.
September 13, moved to near Frederick and encamped.
September 14, division moved to South Mountain and bivouacked.
September 15, moved to Keedysville and bivouacked.
September 16, lay in line of battle.
September 17, battle of Antietam, in which the division took an active part under General mansfield, on the right.
September 18, division lay upon the field in line of battle.
September 19, moved, via Sharpsburg, to Brownsville.
September 20, moved over Maryland Heights, down the mountain, and to near Sandy Hook, and encamped.
September 22, moved upon Maryland Heights.
September 28, moved down the mountain, and again encamped near Sandy Hook, Md, where the division remained until the end of the month.
October 1, the First Brigade encamped near Sandy Hook, Md.
October 2, moved to Maryland Heights, and encamped. The Tenth Maine Volunteers ordered to Berlin, Md., to do picket and guard duty. The Forty-sixth Pennsylvania, Twenty-eighth New york, and one hundred and twenty-eight Pennsylvania Regiments remained on the Heights to the end of the month, doing heavy picket duty up the river from Harper's Ferry to Antietam Creek, and fatigue duty on the mountain.
October 26, by General Orders, Numbers 5 from corps headquarters, the One hundred and twenty-fourth and One hundred and twenty-fifth Pennsylvania Regiments were assigned to the Second Brigade, First Division, Twelfth Corps. The Second Brigade remained at Pleasant Valley, near Sandy Hook, Md., Until October 30, when they moved over to Loudoun Heights, Va., the Twentieth connecticut Volunteers being stationed on the heights, and also the One hundred and twenty-third New York the One hundred and twenty-fourth and One hundred and twenty-fifth Pennsylvania Volunteers on the eastern slope.
The Third Brigade remained on Maryland Heights until October 29, when it was ordered to occupy the position held by General F. J. Porter, near Sharpsburg, Md.
October 30, ordered by General McClellan to report to General Morell, commanding Army of the Upper Potomac.
During the month of November no movement was made by the First Brigade. The regiments were stationed and employed as follows: The Twenty-eighth New York stationed near Sandy Hook, Md., and employed on the fortifications upon Maryland Heights, by Special Orders Numbers 129, Division Headquarters. The Fifth Connecticut Volunteers,