HDQRS. FIRST BRIGADE, SECOND DIVISION,
Arlington, Va., July 25, 1861.

Brig. and Div. Capt. J. B. FRY,
Assistant Adjutant-General.

        SIR: I have the honor to submit the following account of the operations of the First Brigade, Second Division, of the Army, in the battle before Manassas, on the 21st instant. The brigade was silently paraded in light marching order at 2 o'clock in the morning of that day, composed as follows, viz: Griffin's battery; marines, Major Reynolds; Twenty-seventh New York Volunteers, Colonel Slocum; Fourteenth New York State Militia, Colonel Wood; Eighth New York State Militia, Colonel Lyons; battalion regulars, Major Sykes; one company Second Dragoons, two companies First Cavalry, four companies Second Cavalry, Major Palmer. Total strength, 3,700. The marines were recruits, but through the constant exertions of their officers had been brought to present a fine military appearance, without being able to render much active service. They were therefore attached to the battery as its permanent support through the day.
        Owing to frequent delays in the march of troops in front, the brigade did not reach Centreville until 4.30 a.m., and it was an hour after sunrise when the head of it was turned to the right to commence the flank movement. The slow and intermittent movements of the Second Brigade (Burnside's) were then followed through the woods for four hours, which brought the head of our division to Bull Run and Sudley's Mill, where a halt of half an hour took place, to rest and refresh the men and horses. From the heights on this side of the run a vast column of the enemy could be plainly descried, at the distance of a mile or more on our left, moving rapidly towards our line of march in front. Some disposition of skirmishers was then directed to be made at the head of the Column by the division commander, in which Colonel Slocum, of the Second Rhode Island Regiment, was observed to bear an active part. The column moved forward, however, before they were completed, and in about thirty minutes emerged from the timber, when the rattle of musketry and occasional crash of round shot through the leaves and branches of the trees in our vicinity betokened the opening of battle.
        The head of the brigade was immediately turned slightly to the right, in order to gain time and room for deployment on the right of the Second Brigade. Griffin's battery found its way through the timber to the fields beyond, followed promptly by the marines, while the Twenty-seventh took direction more to the left, and the Fourteenth followed upon the trail of the battery, all moving up at a double-quick step. The enemy appeared drawn up in a long line, extending along the Warrenton turnpike from a house and haystacks upon our extreme right to a house beyond the left of the division. Behind that house there was a heavy masked battery, which, with three others along his line on the heights beyond, covered the ground upon which we were advancing with all sorts of projectiles. A grove in front of his right wing afforded it shelter and protection, while the shrubbery along the road, with fences, screened somewhat his left wing. Griffin advanced to within a thousand yards, and opened a deadly and unerring fire upon his batteries, which were soon silenced or driven away. Our right was rapidly developed by the marines, Twenty-seventh, Fourteenth, and Eighth, with the cavalry in rear of the right, the enemy retreating with more precipitation than order as our line advanced.
        The Second Brigade (Burnside's) was at this time attacking the enemy's right with, perhaps, too hasty vigor. The enemy clung to the protecting wood with great tenacity, and the Rhode Island Battery became so much endangered as to impel the commander of the Second Brigade to call for the assistance of the battalion of regulars. At this time I received the information through Capt. W. D. Whipple, A. A. G., that Colonel Hunter was seriously wounded, and had directed him to report to me as commander of the division; and in reply to the urgent request of Colonel Burnside, I detached the battalion of regulars to his assistance. For an account of its operations I would respectfully beg a reference to the inclosed report of its commander, Major Sykes [No. 35].
        The rebels soon come flying from the woods towards the right, and the Twenty-seventh completed their rout by charging directly upon their center in the face of a scorching fire, while the Fourteenth and Eighth moved down the turnpike to cut off the retiring foe, and to support the Twenty-seventh, which had lost its gallant colonel, but was standing the brunt of the action, with its ranks thinning in the dreadful fire. Now the resistance of the enemy's left was so obstinate that the beaten right retired in safety.
        The head of Heintzelman's column at this moment appeared upon the field, and the Eleventh and Fifth Massachusetts Regiments moved forward to the support of our center, while staff officers could be seen galloping rapidly in every direction, endeavoring to rally the broken Eighth; but this laudable purpose was only partially attained, owing to the inefficiency of some of its field officers.
        The Fourteenth, though it had broken, was soon rallied in rear of Griffin's battery, which soon took up a position farther to the front and right, from which his fire was delivered with such precision and rapidity as to compel the batteries of the enemy to retire in consternation far behind the brow of the hill in front. At this time my brigade occupied a line considerably in advance of that first occupied by the left wing of the enemy. The battery was pouring its withering fire into the batteries and columns of the enemy whenever they exposed themselves. The cavalry were engaged in feeling the left flank of the enemy's positions, in doing which some important captures were made--one by Sergeant Sacks, of the Second Dragoons, of a General George Steuart, of Baltimore. Our cavalry also emptied the saddles of a number of the mounted rebels.
        General Tyler's division was engaged with the enemy's right. The Twenty-seventh was resting in the edge of the woods, in the center, covered by a hill, upon which lay the Eleventh and Fifth Massachusetts, occasionally delivering a scattering fire. The Fourteenth was moving to the right flank. The Eighth had lost its organization. The marines were moving up in fine style in rear of the Fourteenth, and Captain Arnold was occupying a height on the middle ground with his battery. At this juncture there was a temporary lull in the firing from the rebels, who appeared only occasionally on the heights in irregular formations, but to serve as marks for Griffin's guns.
        The prestige of success had thus far attended the efforts of our inexperienced, but gallant, troops. The lines of the enemy had been forcibly shifted nearly a mile to their left and rear. The flags of eight regiments, though borne somewhat wearily, now pointed towards the hill from which disordered masses of rebels had been seen hastily retiring.
        Griffin's and Ricketts' batteries were ordered by the commanding general to the top of the hill on our right, supporting them with Fire Zouaves and marines, while the Fourteenth entered the skirt of woods on their right, to protect that flank, and a column, composed of the Twenty-seventh New York, Eleventh and Fifth Massachusetts, First Minnesota, and Sixty ninth New York, moved up towards the left flank of the batteries; but so soon as they were in position, and before the flanking supports had reached theirs, a murderous fire of musketry and rifles, opened at pistol range, cut down every cannoneer and a large number of horses. The fire came from some infantry of the enemy, which had been mistaken for our own forces, an officer on the field having stated that it was a regiment sent by Colonel Heintzelman to support the batteries.
        The evanescent courage of the zouaves prompted them to fire perhaps a hundred shots, when they broke and fled, leaving the batteries open to a charge of the enemy's cavalry, which took place immediately. The marines also, in spite of the exertions of their gallant officers, gave way in disorder; the Fourteenth on the right and the column on the left hesitatingly retired, with the exception of the Sixty-ninth and Thirty-eighth New York, who nobly stood and returned the fire of the enemy for fifteen minutes. Soon the slopes behind us were swarming with our retreating and disorganized forces, whilst riderless horses and artillery teams ran furiously through the flying crowd. All further efforts were futile; the words, gestures, and threats of our officers were thrown away upon men who had lost all presence of mind and only longed for absence of body. Some of our noblest and best officers lost their lives in trying to rally them.
        Upon our first position the Twenty-seventh was the first to rally, under the command of Major Bartlett, and around it the other regiments engaged soon collected their scattered fragments. The battalion of regulars, in the mean time, moved steadily across the held from the left to the right, and took up a position where it held the entire forces of the rebels in check until our forces were somewhat rallied. The commanding general then ordered a retreat upon Centreville, at the same time directing me to cover it with the battalion of regulars, the cavalry, and a section of artillery. The rear guard thus organized followed our panic-stricken people to Centreville, resisting the attacks of the rebel cavalry and artillery, and saving them from the inevitable destruction which awaited them had not this body been interposed.
        Among those who deserve especial mention I beg leave to place the following names, viz:
        Captain Griffin, for his coolness and promptitude in action, and for the handsome manner in which he handled his battery. Lieutenant Ames, of the same battery, who, after being wounded, gallantly served with it in action, and being unable to ride on horseback, was helped on and off a caisson in changes of position.
        Captain Tillinghast, A. Q. M., who was ever present where his services were needed, carrying orders, rallying troops, and serving with the batteries, and finally, I have to state with the deepest sorrow, was mortally wounded.
        Major Sykes and the officers of his command, three of whom (Lieutenants Latimer, Dickinson, and Kent) were wounded, who by their discipline, steadiness, and heroic fortitude, gave eclat to our attacks upon the enemy, and averted the dangers of a final overthrow.
        Major Palmer and the cavalry officers under him, who by their daring intrepidity made the effectiveness of that corps all that it could be upon such a field in supporting batteries, feeling the enemy's position, and covering our retreat.
        Major Reynolds, marines, whose zealous efforts were well sustained by his subordinates, two of whom, Brevet Major Zeilin and Lieutenant Hale, were wounded, and one, Lieutenant Hitchcock, lost his life.
        Col. H. W. Slocum, who was wounded while leading his gallant Twenty-seventh New York to the charge, and Maj. J. J. Bartlett, who subsequently commanded it, and by his enthusiasm and valor kept it in action and out of the panic. His conduct was imitated by his subordinates, of whom two, Capt. H. C. Rodgers and Lieut. H. C. Jackson, were wounded, and one, Ensign Asa Park, was killed.
        In the last attack Col. A.M. Wood, of the Fourteenth New York State Militia, was wounded, together with Capts. R. B. Jordan and C. F. Baldwin, and Lieuts. J. A. Jones, T. R. Salter, R. A. Goodenough, and C. Scholes, and Adjutant Laidlaw.
        The officers of the Fourteenth, especially Maj. James Jourdan, were distinguished by their display of spirit and efficiency throughout the action.
        Surg. Charles C. Keeney, of the medical department, who by his professional skill, promptitude, and cheerfulness made the condition of the wounded of the Second Division comparatively comfortable. (He was assisted to a great extent by Dr. Rouch, of Chicago, a citizen.)
        During the entire engagement I received extremely valuable aid and assistance from my aides-de-camp, Lieuts. C. F. Trowbridge and F. M. Bache, both of the Sixteenth Infantry.
        Lieut. J. B. Howard, Fourteenth New York State Militia, A. A. Q. M. for the brigade, who by zealous attention to his duties succeeded in safely bringing the wagons of my brigade to Arlington.
        The staff officers of the Second Division commander, via, Capt. W. D. Whipple, Lieutenants Cross and Flagler, served with me after the fall of Colonel Hunter, and I am indebted to them for gallant, faithful services during the day. Captain Whipple had his horse killed under him by a cannon ball.
        Acting Asst. Adjt. General Lieut. W. W. Averell sustained the high reputation he had before won for himself as a brave and skillful officer, and to him I am very greatly indebted for aid and assistance, not only in performing with the greatest promptitude the duties of his position, but by exposing himself most fearlessly in rallying and leading forward the troops, he contributed largely to their general effectiveness against the enemy. I desire to call the attention of the commanding general particularly to him.
        In conclusion, I beg leave to submit the inclosed return of killed, wounded, and missing in my brigade. Since the above reports were handed in many of the missing have returned, perhaps one-third of those reported. The inclosed report of Colonel Burnside, [No. 39], commanding Second Brigade, was sent to me after the above report was written. While respectfully calling the attention of the general commanding to it, I would also ask leave to notice some misconceptions under which the colonel commanding the Second Brigade seems to have labored at the time of writing his report, viz: Of his agency in the management or formation of the Second Division, on the field; 2d, of the time that his brigade was entirely out of the action, with the exception of the New Hampshire Regiment; 3d, of the position of his brigade in the retreat, and particularly of the position of the Seventy-first New York, as he may have mistaken the rear guard, organized under my direction by your orders, for the enemy.
        Captain Arnold's battery and the cavalry were directed and placed in their positions by my senior staff officer up to the time when Colonel Heintzelman ordered the cavalry to the front of the column.

Very respectfully, your obedient servant,
A. PORTER,
Colonel Sixteenth Infantry, U.S. Army, Comdg