Doc. 2.-General McClellan's report of the operations after the evacuation of Harrison's Landing.
headquarters army of the Potomac, October 15, 1862.General: I have the honor to submit a preliminary report of the military operations under my charge since the evacuation of Harrison's Landing. The measure directed by the General-in-Chief was executed successfully with entire safety to my command and its material, between the fourteenth and nineteenth of August. The line of withdrawal selected was that of the mouth of the Chickahominy, Williamsburgh, and Yorktown. Upon this line the main body of the army with all its trains was moved, Heintzelman's corps crossing the Chickahominy at Jones's Bridge, and covering by its march the movement of the main column. The passage of the Lower Chickahominy was effected by means of a batteau bridge two thousand feet in length. The transfer of the army to Yorktown was completed by the nineteenth of August. The embarkation of the troops and material at Yorktown and Fortress Monroe was at once commenced, and as rapidly as the means of transportation admitted, every thing was sent forward to Acquia Creek and Alexandria. No mere sketch of an undertaking of such magnitude and yet so delicate a military character will suffice to do justice. I must now, however, content myself with a simple notice of it, deferring a full description for my official report of the campaign before Richmond — a labor which I propose to undertake as soon as events will afford me the necessary time. Justice to the achievements of the Army of the Potomac, and the brave men who composed it, requires that the official record of that campaign should he prepared with more care than circumstances have hitherto permitted me to bestow upon it. The delay will not have been felt as injurious to the public interest, inasmuch as by frequent reports from time to time I have kept the Department advised of events as they occurred. I reached Acquia Creek with my staff on the twenty-fourth of August, reported my arrival, and asked for orders. On the twenty-seventh of August I received from the General in-Chief permission to proceed to Alexandria, where I at once fixed my headquarters. The troops composing the army of the Potomac were meanwhile ordered forward to reenforce the army under Gen. Pope. So completely was this order carried out, that on the thirtieth of August I had remaining under my command only a camp-guard of about one hundred men. Every thing else had been sent to reenforce Gen. Pope. In addition, I exhausted all the means at my disposal to forward supplies to that officer, my own headquarter teams even being used for that purpose. Upon the unfortunate issue of that campaign I received an intimation from the General-in-Chief that my services were desired for the purpose of arranging for the defence of the capital. They were at once cheerfully given, although, while awaiting definite instructions at Alexandria, I had endeavored, as just seen, to promote a favorable result in the operations then pending, and had thus contributed, though indirectly, yet as far as I could, to the defence of Washington. On the second of September the formal order of the War Department placed me in command of the fortifications of Washington, “and of all the troops for the defence of the capital.” On the first of September I had been instructed that I had nothing to do with the troops engaged in active operations under Gen. Pope, but that my command was limited to the immediate garrison of Washington. On the next day, however, I was verbally instructed by the President and  General-in-Chief to assume command of General Pope's troops, (including my own army of the Potomac,) as soon as they approached the vicinity of Washington, to go out and meet them and to post them as I deemed best to repulse the enemy and insure the safety of the city. At this time the task imposed upon me was limited to the dispositions necessary to resist a direct attack of the enemy upon the capital. Such, indeed, was the danger naturally indicated by the defeat of our forces in front. The various garrisons were at once strengthened and put in order, and the troops were disposed to cover all the approaches to the city, and so as to be readily thrown upon threatened points. New defences were thrown up where deemed necessary. A few days only had elapsed before comparative security was felt with regard to our ability to resist any attack upon the city. The disappearance of the enemy from the front of Washington and their passage into Maryland enlarged the sphere of operations, and made an active campaign necessary to cover Baltimore, prevent the invasion of Pennsylvania, and drive them out of Maryland. Being honored with the charge of this campaign, I entered at once upon the additional duties imposed upon me with cheerfulness and trust, yet not without feeling the weight of the responsibilities thus assumed, and being deeply impressed with the magnitude of the issues involved. Having made the necessary arrangements for the defence of the city in the new condition of things, I pushed forward the First and Ninth corps, under Generals Reno and Hooker, forming the right wing under General Burnside, to Leesburgh, on the fifth instant; thence, the First corps, by Brooksville, Cooksville, and Ridgeville, to Frederick, and the Ninth corps, by Damascus, on New-Market and Frederick. The Second and Eleventh corps, under Generals Sumner and Williams, on the sixth were moved from Tenallytown to Rockville, thence by Middlebury and Urbana on Frederick, the Eleventh corps moving by a lateral road between Urbana and New-Market, thus maintaining the communication between the centre and right wing, as well as covering the direct route from Frederick to Washington. The Sixth corps, under Gen. Franklin, was moved to Darnestown on the sixth instant, thence by Dawsonville and Barnsville on Buckeystown, covering the road from the mouth of the Monocacy to Rockville, and being in position to connect with and support the centre should it have been necessary (as was supposed) to force the line of the Monocacy. Couch's division was thrown forward to Offut's Cross-Roads and Poolesville by the river road, thus covering that approach, watching the fords of the Potomac, and ultimately following and supporting the Sixth corps. The object of these movements was to feel the enemy — to compel him to develop his intentions — at the same time that the troops were in position readily to cover Baltimore or Washington, to attack him should he hold the line of the Monocacy, or to follow him into Pennsylvania if necessary. On the twelfth, a portion of the right wing entered Frederick after a brisk skirmish at the outskirts of the city and in its streets. On the thirteenth, the main bodies of the right wing and centre passed through Frederick. In this city the manifestations of Union feeling were abundant and gratifying. The troops received the most enthusiastic welcome at the hands of the inhabitants. On the thirteenth, the advance, consisting of Pleasanton's cavalry and horse artillery, after some skirmishing, cleared the main passage over the Catoctin Hills, leaving no serious obstruction to the movement of the main body until the base of the South-Mountain range was reached. While at Frederick, on the thirteenth, I obtained reliable information of the movements and intentions of the enemy, which made it clear that it was necessary to force the passage of the South-Mountain range and gain possession of Boonsboro and Rohrersville before any relief could be afforded to Harper's Ferry. On the morning of the thirteenth I received a verbal message from Col. Miles, commanding at Harper's Ferry, informing me that on the preceding afternoon the Maryland Heights had been abandoned, after repelling an attack by the rebels, and that the whole force was concentrated at Harper's Ferry, the Maryland, Loudon and Bolivar Heights being all in possession of the enemy. The messenger stated that there was no apparent reason for the abandonment of the Maryland Heights, and that, though Col. Miles asked for assistance, he said he could hold out certainly two days. I directed him to make his way back, if possible, with the information that I was rapidly approaching, and would undoubtedly relieve the place. By three other couriers I sent the same message, with the order to hold out to the last. I do not learn that any of these messengers succeeded in reaching Harper's Ferry. I should here state that on the twelfth I was directed to assume command of the garrison at Harper's Ferry, but this order reached me after all communication with the garrison was cut off. Before I left Washington, and while it was yet time, I recommended to the proper authorities that the garrison of Harper's Ferry should be withdrawn via Hagerstown, to aid in covering the Cumberland Valley, or that, taking up the pontoon bridge and obstructing the railroad bridge, it should fall back to the Maryland Heights, and there hold its own to the last. In this position it could have maintained itself for weeks. It was not deemed proper to adopt either of these suggestions, and when the subject was left to my discretion it was too late to do any thing except to try to relieve the garrison. I directed artillery to be frequently fired by our advanced guards as a signal to the garrison that relief was at hand. This was done, and I learn that our firing was distinctly heard at Harper's Ferry, and that they were thus made aware that we were approaching rapidly. It was confidently expected that this place could hold out until we had carried the mountains, and were in a position  to make a detachment for its relief. The left, therefore, was ordered to move through Jefferson to the South-Mountains, at Crampton's Pass, in front of Burkettsville, while the centre and right moved upon the main or Turner's Pass, in front of Middletown. During these movements I had not imposed long marches on the columns. The absolute necessity of refitting and giving some little rest to troops worn down by previous long-continued marching and severe fighting, together with the uncertainty as to the actual position, strength and intentions of the enemy, rendered it incumbent upon me to move slowly and cautiously until the headquarters reached Urbana, where I first obtained reliable information that the enemy's object was to move upon Harper's Ferry and the Cumberland Valley, and not upon Baltimore, Washington or Gettysburgh. In the absence of the full reports of corps commanders, a simple outline of the brilliant operations, which resulted in the carrying of the two passes through the South-Mountains, is all that can, at this time, with justice to the troops and commanders engaged, be furnished. The South-Mountain range, near Turner's Pass, averages perhaps a thousand feet in height, and forms a strong natural military barrier. The practicable passes are not numerous, and are readily defensible, the gaps abounding in fine positions. Turner's Pass is the more prominent, being that by which the national road crosses the mountains. It was necessarily indicated as the route of advance of our main army. The carrying of Crampton's Pass some five or six miles below, was also important to furnish the means of reaching the flank of the enemy, and having as a lateral movement, direct relations to the attack on the principal pass, while it at the same time presented the most direct practical route for the relief of Harper's Ferry. Early in the morning of the fourteenth instant, General Pleasanton, with a cavalry force, reconnoitred the position of the enemy, whom he discovered to occupy the crests of commanding hills in the gap on either side of the national road, and upon advantageous ground in the centre upon and near the road, with artillery bearing upon all the approaches to their position, whether that by the main road or those by the country roads which led around up to the crest upon the right and left. At about eight o'clock A. M., Cox's division of Reno's corps, a portion of Burnside's column, in cooperation with the reconnaissance, which by this time had become an attack, moved up the mountain by the old Sharpsburgh road to the left of the main road, dividing as they advanced into two columns. These columns (Scammon's and Cook's brigades) handsomely carried the enemy's position on the crest in their front, which gave us possession of an important point for further operations. Fresh bodies of the enemy now appearing, Cox's position, though held stubbornly, became critical, and between twelve and one o'clock P. M. Wilcox's division of Reno's corps was sent forward by Gen. Burnside to support Cox, and between two and three P. M. Sturgis's division was sent up. The contest was maintained with perseverance until dark, the enemy having the advantage as to position, and fighting with obstinacy; but the ground won was fully maintained. The loss in killed and wounded here was considerable on both sides; and it was here that Major-General Reno, who had gone forward to observe the operations of his corps, and to give such directions as were necessary, fell pierced with a musketball. The loss of this brave and distinguished officer, tempered with sadness the exultations of triumph. A gallant soldier, an able general, endeared to his troops and associates, his death is felt as an irreparable misfortune. About three o'clock P. M., Hooker's corps, of Burnside's column, moved up to the right of the main road by a country road, which, bending to the right, then turning up to the left, circuitously wound its way beyond the crest of the pass to the Mountain House, on the main road. Gen. Hooker sent Meade, with the division of Pennsylvania reserves, to attack the eminence to the right of this entrance to the gap, which was done most handsomely and successfully. Patrick's brigade, of Hatch's division, was sent--one portion up around the road, to turn the hill on the left, while the remainder advanced as skirmishers — up the hill, and occupied the crest, supported by Doubleday's and Phelps's brigades. The movement, after a sharp contest on the crest and in the fields in the depression between the crest and the adjoining hill, was fully successful. Ricketts's division pressed up the mountain about five P. M., arriving at the crest with the left of his command in time to participate in the closing scene of the engagement. Relieving Hatch's division, Ricketts remained on the ground, holding the battle-field during the night. The mountain sides thus gallantly passed over by Hooker on the right of the gap and Reno on the left, were steep and difficult in the extreme. We could make but little use of our artillery, while our troops were subject to a warm artillery fire, as well as to that of infantry in the woods and under cover. By order of Gen. Burnside, Gibbon's brigade, of Hatch's division, late in the afternoon advanced upon the centre of the enemy's position on the main road. Deploying his brigade, Gibbon actively engaged a superior force of the enemy, which, though stubbornly resisting, was steadily pressed back until some hours after dark, when Gibbon remained in undisturbed possession of the field. He was then relieved by a brigade of Sedgwick's division. Finding themselves outflanked, both on the right and left, the enemy abandoned their position during the night, leaving their dead and wounded on the field, and hastily retreated down the mountain. In the engagement at Turner's Pass our loss was three hundred and twenty-eight killed, and one thousand four hundred and sixty three wounded and missing; that of the enemy is estimated  to be, in all, about three thousand. Among our wounded, I regret to say, were Brig.-Gen. J. P. Hatch and other valuable officers. The carrying of Crampton's Pass by Franklin was executed rapidly and decisively. Slocum's division was formed upon the right of the road leading through the gap, Smith's upon the left. A line, formed of Bartlett's and Torbitt's brigades, supported by Newton, whose activity was conspicuous, (all of Slocum's division,) advanced steadily upon the enemy at a charge on the right. The enemy were driven from their position at the base of the mountain, where they were protected by a stone wall, and steadily forced back up the mountain until they reached the position of their battery near the road, well up the mountain. Here they made a stand. They were, however, driven back, retiring their artillery in echelon until, after an action of three hours, the crest was gained, and the enemy fled hastily down the mountains on the other side. On the left of the road Brooks's and Irwin's brigades, of Smith's division, formed for the protection of Slocum's flank, charged up the mountain in the same steady manner, driving the enemy before them until the crest was carried. The loss in Franklin's corps was one hundred and fifteen killed, four hundred and sixteen wounded, and two missing. The enemy's loss was about the same. One piece of artillery and four colors were captured, and knapsacks, and even haversacks, were abandoned as the enemy were driven up the hill. On the morning of the fifteenth I was informed by Union civilians living on the side of the mountains that the enemy were retreating in the greatest haste and in disordered masses to the river. There was such a concurrence of testimony on this point that there seemed no doubt as to the fact. The hasty retreat of the enemy's forces from the mountain, and the withdrawal of the remaining troops from between Boonsboro and Hagerstown to a position where they could resist attack and cover the Shepherdstown Ford, and receive the reenforcements expected from Harper's Ferry, were for a time interpreted as evidences of the enemy's disorganization and demoralization. As soon as it was definitely known that the enemy had abandoned the mountains, the cavalry, and the corps of Sumner, Hooker and Mansfield were ordered to pursue them via the turnpike and Boonsboro, as promptly as possible. The corps of Burnside and Porter (the latter having but one weak division present) were ordered to move by the old Sharpsburgh road, and Franklin to advance into Pleasant Valley, occupy Rohrersville, and to endeavor to relieve Harper's Ferry. Burnside and Porter, upon reaching the road from Boonsboro to Rohrersville, were to reenforce Franklin or move on Sharpsburgh, according to circumstances. Franklin moved toward Brownsville, and found there a force largely superior in numbers to his own, drawn up in a strong position to receive him. Here the total cessation of firing in the direction of Harper's Ferry indicated but too clearly the shameful and premature surrender of that post. The cavalry advance overtook a body of the enemy's cavalry at Boonsboro, which it dispersed after a brief skirmish, killing and wounding many, taking some two hundred and fifty prisoners and two guns. Richardson's division, of Sumner's corps, passing from Boonsboro to Kedysville, found, a few miles beyond the town, the enemy's forces, displayed in line of battle, strong, both in respect to numbers and position, and awaiting attack. Upon receiving reports of the disposition of the enemy, I directed all the corps, except that of Franklin, upon Sharpsburgh, leaving Franklin to observe and check the enemy in his front, and avail himself of any chance that might offer. I had hoped to come up with the enemy, during the fifteenth, in sufficient force to beat them again, and drive them into the river. My instructions were, that if the enemy were not on the march, they were to be at once attacked; if they were found in force and position, the corps were to be placed in position for attack, but no attack was to be made until I reached the front. On arriving at the front in the afternoon, I found but two divisions, Richardson's and Sykes's, in position; the rest were halted in the road, the head of the column some distance in rear of Richardson. After a rapid examination of the position, I found that it was too late to attack that day, and at once directed locations to be selected for our batteries of position, and indicated the bivouacs for the different corps, massing them near and on both sides of the Sharpsburgh pike. The corps were not all in their places until the next morning, some time after sunrise. On the sixteenth the enemy had slightly changed their line, and were posted upon the heights in the rear of the Antietam Creek, their left and centre being upon and in front of the road from Sharpsburgh to Hagerstown, and protected by woods and irregularities of the ground. Their extreme left rested upon a wooded eminence near the cross-roads to the north of J. Miller's farm, the distance at this point between the road and the Potomac, which makes here a great bend to the east, being about three fourths of a mile. Their right rested on the hills to the right of Sharpsburgh, near Snavely's farm, covering the crossing of the Antietam, and the approaches to the town from the south-east. The ground from their immediate front and the Antietam is undulating. Hills intervene whose crests in general are commanded by the crests of others in their rear. On all favorable points, their artillery was posted. It became evident from the force of the enemy and the strength of their position, that desperate fighting alone could drive them from the field, and all felt that a great and terrible battle was at hand. In proceeding to the narrative of the events of this and the succeeding day, I must here repeat what I have observed in reporting upon the other subjects of this communication, that I attempt in  this preliminary report nothing more than a sketch of the main features of this great engagement, reserving for my official report, based upon the reports of the corps commanders, that full description of details which shall place upon record the achievements of individuals and of particular bodies of troops. The design was to make the main attack upon the enemy's left — at least, to create a diversion in favor of the main attack, with the hope of something more — by assailing the enemy's right, and as soon as one or both of the flank movements were fully successful, to attack their centre with any reserve I might then have on hand. The morning of the sixteenth (during which there was considerable artillery firing) was spent in obtaining information as to the ground, rectifying the position of the troops, and perfecting the arrangements for the attack. On the afternoon of the sixteenth Hooker's corps, consisting of Ricketts's and Doubleday's divisions, and the Pennsylvania reserves, under Meade, was sent across the Antietam Creek, by a ford and bridge to the right of Kedysville, with orders to attack, and, if possible, turn the enemy's left. Mansfield, with his corps, was sent in the evening to support Hooker. Arrived in position, Meade's division of the Pennsylvania reserves, which was at the head of Hooker's corps, became engaged in a sharp contest with the enemy, which lasted until after dark, when it had succeeded in driving in a portion of the opposing line, and held the ground. At daylight the contest was renewed between Hooker and the enemy in his front. Hooker's attack was successful for a time, but masses of the enemy, thrown upon his corps, checked it. Mansfield brought up his corps to Hooker's support, when the two corps drove the enemy back, the gallant and distinguished veteran Mansfield losing his life in the effort. Gen. Hooker was, unhappily, about this time wounded, and compelled to leave the field, where his services had been conspicuous and important. About an hour after this time, Sumner's corps, consisting of Sedgwick's, Richardson's and French's divisions, arrived on the field — Richardson some time after the other two, as he was unable to start as soon as they. Sedgwick, on the right, penetrated the woods in front of Hooker's and Mansfield's troops. French and Richardson were placed to the left of Sedgwick, thus attacking the enemy toward their left centre. Crawford's and Sedgwick's lines, however, yielded to a destructive fire of masses of the enemy in the woods, and, suffering greatly, (Generals Sedgwick and Crawford being among the wounded,) their troops fell back in disorder; they, nevertheless, rallied in the woods. The enemy's advance was, however, entirely checked by the destructive fire of our artillery. Franklin, who had been directed the day before to join the main army with two divisions, arrived on the field from Brownsville about an hour after, and Smith's division replaced Crawford's and Sedgwick's lines. Advancing steadily, it swept over the ground just lost, but now permanently retaken. The divisions of French and Richardson maintained with considerable loss the exposed positions which they had so gallantly gained, among the wounded being Gen. Richardson. The condition of things on the right toward the middle of the afternoon, notwithstanding the success wrested from the enemy by the stubborn bravery of the troops, was at this time unpromising. Sumner's, Hooker's and Mansfield's corps had lost heavily, several general officers having been carried from the field. I was at one time compelled to draw two brigades from Porter's corps (the reserve) to strengthen the right. This left for the reserve the small division of regulars who had been engaged in supporting during the day the batteries in the centre, and a single brigade of Morell's division. Before I left the right to return to the centre, I became satisfied that the line would be held without these two brigades, and countermanded the order which was in course of execution. The effect of Burnside's movement on the enemy's right was to prevent the further massing of their troops on their left, and we held what we had gained. Burnside's corps, consisting of Wilcox's, Sturgis's and Rodman's divisions, and Cox's Kanawha division, was intrusted with the difficult task of carrying the bridge across the Antietam, near Rohrback's firm, and assaulting the enemy's right, the order having been communicated to him at ten o'clock A. M. The valley of the Antietam, at and near the bridge, is narrow, with high banks. On the right of the stream the bank is wooded, and commands the approaches both to the bridge and the ford. The steep slopes of the bank were lined with rifle-pits and breastworks of rails and stones. These, together with the woods, were filled with the enemy's infantry, while their batteries completely commanded and enfiladed the bridge and ford and their approaches. The advance of the troops brought on an obstinate and sanguinary contest, and from the great natural advantages of the position, it was nearly one o'clock before the heights on the right bank were carried. At about three o'clock P. M. the corps again advanced, and with success, driving the enemy before it, and pushing on nearly to Sharpsburgh, while the left, after a hard encounter, also compelled the enemy to retire before it. The enemy here, however, were speedily reenforced, and with overwhelming masses. New batteries of their artillery, also, were brought up and opened. It became evident that our force was not sufficient to enable the advance to reach the town, and the order was given to retire to the cover of the hill, which was taken from the enemy earlier in the afternoon. This movement was effected without confusion, and the position maintained until the enemy retreated. Gen. Burnside had sent to me for reenforcements late in the afternoon, but the condition of things on the right was not such as to enable me to afford them. During the whole day our artillery was everywhere bravely and ably handled. Indeed, I cannot  speak too highly of the efficiency of our batteries, and of the great service they rendered. On more than one occasion, when our infantry was broken, they covered its re-formation, and drove back the enemy. The cavalry had little field for operation during the engagement, but was employed in supporting the horse-artillery batteries in the centre, and in driving up stragglers, while awaiting opportunity for other service. The signal corps, under Major Myers, rendered during the operations at Antietam, as at South-Mountain, and during the whole movements of the army, efficient and valuable service. Indeed, by its services here, as on other fields elsewhere, this corps has gallantly earned its title to an independent and permanent organization. The duties devolving upon my staff during the action were most important, and the performances of them able and untiring. At a later day I propose to bring to the notice of the department their individual services. With the day closed this memorable battle, in which, perhaps, nearly two hundred thousand men were for fourteen hours engaged in combat. We had attacked the enemy in position, driven them from their line on one flank, and secured a footing within it on the other. Under the depression of previous reverses, we had achieved a victory over an adversary invested with the prestige of former successes and inflated with a recent triumph. Our forces slept that night conquerors on a field won by their valor, and covered with the dead and wounded of the enemy. The night, however, presented serious questions ; morning brought on grave responsibilities. To renew the attack again on the eighteenth, or to defer it, with the chance of the enemy's retirement after a day of suspense, were the questions before me. A careful and anxious survey of the condition of my command, and my knowledge of the enemy's force and position, failed to impress me with any reasonable certainty of success, if I renewed the attack without reinforcing columns. A view of the shattered state of some of the corps sufficed to deter me from pressing them into immediate action, and I felt that my duty to the army and the country forbade the risks involved in a hasty movement, which might result in the loss of what had been gained the previous day. Impelled by this consideration, I awaited the arrival of my reenforcements, taking advantage of the occasion to collect together the dispersed, give rest to the fatigued, and remove the wounded. Of the reenforcements, Couch's division, although marching with commendable rapidity, was not in position until a late hour in the morning; and Humphrey's division of new troops, fatigued with forced marches, were arriving throughout the day, but were not available until near its close. Large reenforcements from Pennsylvania, which were expected during the day, did not arrive at all. During the eighteenth, orders were given for a renewal of the attack at daylight on the nineteenth. On the night of the eighteenth, the enemy, after having been passing troops in the latter part of the day from the Virginia shore to their position behind Sharpsburgh, as seen by our officers, suddenly formed the design of abandoning their line. This movement they executed before daylight. Being but a short distance from the river, the evacuation presented but little difficulty. It was, however, rapidly followed up. A reconnoissance was made across the river on the evening of the nineteenth, which resulted in ascertaining the near presence of the enemy in some force, and in our capturing six guns. A second reconnoissance, the next morning, which, with the first, was made by a small detachment from Porter's corps, resulted in observing a heavy force of the enemy there. The detachment withdrew with slight loss. I submit herewith a list of the killed, wounded and missing in the engagements of the fifteenth, and of the sixteenth and seventeenth. The enemy's loss is believed, from the best sources of information, to be nearly thirty thousand. Their dead were mostly left on the field, and a large number of wounded were left behind. While it gives me pleasure to speak of the gallantry and devotion of officers and men, generally displayed throughout this conflict, I feel it necessary to mention that some officers and men skulked from their places in the ranks until the battle was over. Death on the spot must hereafter be the fate of all such cowards, and the hands of the military commanders must be strengthened with all the power of the Government to inflict it summarily. The early and disgraceful surrender of Harper's Ferry deprived my operations of results which would have formed a brilliant sequence to the substantial and gratifying success already related. Had the garrison held out twenty-four hours longer, I should in all probability, have captured that part of the enemy's force engaged in the attack on the Maryland Heights, while the whole garrison, some twelve thousand strong, could have been drawn to reenforce me on the day of the decisive battle-certainly on the morning of the eighteenth. I would thus have been in a position to have destroyed the rebel army. Under the same circumstances, had the besieging force on the Virginia side at Harper's Ferry not been withdrawn, I would have had thirty-five or forty thousand less men to encounter at Antietam, and must have captured or destroyed all opposed to me. As it was, I had to engage an army fresh from a recent, and to them a great victory, and to reap the disadvantages of their being freshly and plentifully supplied with ammunition and supplies. The object and results of this brief campaign may be summed up as follows: In the beginning of the month of September, the safety of the National capital was seriously endangered by the presence of a victorious enemy, who soon after crossed into Maryland, and then directly threatened Washington and Baltimore, while they occupied the soil of a loyal State, and threatened an invasion of Pennsylvania. The army of the  Union, inferior in numbers, wearied by long marches, deficient in various supplies, worn out by numerous battles, the last of which had not been successful, first covered, by its movements, the important cities of Washington and Baltimore; then boldly attacked the victorious enemy in their chosen strong position, and drove them back, with all their superiority of numbers, into the State of Virginia; thus saving the loyal States from invasion, and rudely dispelling the rebel dreams of carrying the war into our country and subsisting upon our resources. Thirteen guns and thirty-nine colors, more than fifteen thousand stand of small arms, and more than six thousand prisoners, were the trophies which attest the success of our arms. Rendering thanks to Divine Providence for its blessing upon our exertions, I close this brief report. I beg only to add the hope that the army's efforts for the cause in which we are engaged will be deemed worthy to receive the commendation of the Government and the country. I am, very respectfully, your obedient servant,