CAMP NEAR CENTREVILLE, VA.,
October 17, 1863.

SIR: I have the honor to report that this regiment broke camp, near Culpeper, Va., on morning of the 10th instant, and took up position about 1 miles to the right of Culpeper. Next morning, at  2.30. a.m., fell back, with remainder of the Second Corps, and crossed the Rappahannock River at Rappahannock Station, encamping same night at Bealeton Station.

On the 11th instant, recrossed the river at Rappahannock Station and formed line of battle, advanced about 2 miles, and encamped. About 12.30 a.m. of the 12th instant, broke camp and again crossed the river, marching past Bealeton Station and to within 2 miles of Sulphur Springs. Then changed direction of march and proceeded to within 3 miles of Warrenton Junction, when course of march was again changed, and we advanced in the direction of Warrenton, and encamped for the night near Auburn.

On morning of the 14th instant, proceeded to crest of a hill near Auburn, when fire was opened upon us by a rebel battery, with no casualties on our part. We then proceeded to ------- -------, when, having taken a position, were ordered, with the balance of brigade, to act as skirmishers on the right flank of the position then occupied by this division. We were soon afterward withdrawn, and, with the remainder of the division, marched to a position near Bristoe Station, and formed line of battle on the right of the railroad. At the time of our arrival at this position the advance of our corps were engaged with the enemy, who were also in line of battle in front of the position we then occupied. We remained here for several hours, part of the time being under the fire of the enemy's batteries, but suffered no casualties, on account of being protected by the railroad embankment. About 9.30 p.m., same day, resumed march, and, after crossing Bull Run at Blackburn's Ford, came to present camp, where we have since remained.

I have the honor to be, sir, very respectfully, your obedient servant,

RICHARD BYRNES,

Colonel, Commanding.

Capt. W. S. BAILEY,

Acting Assistant Adjutant-General.