The troops were greatly overcome by the fatigue and exhaustion attendant upon the long continued and severely contested battle of the 17th, together with the long day and night marches to which they had been subjected during the previous three days. The supply trains were in the rear, and many of the troops had suffered from hunger. They required rest and refreshment. One division of Sumner's and all of Hooker's corps on the right had, after fighting most valiantly for several hours, been overpowered by numbers, driven back in great disorder, and much scattered, so that they were for the time somewhat demoralized. In Hooker's corps, according to the return made by General Meade, commanding, there were but 6,729 men present on the 18th, whereas on the morning of the 22nd there were 13,093 men present for duty in the same corps, showing that previous to and during the battle 6,364 men were separated from their command.

General Meade, in an official communication upon this subject, dated September 18, 1862, says:

I inclose a field return of the corps made this afternoon, which I desire you will lay before the commanding general. I am satisfied the great reduction in the corps since the recent engagements is not due solely to the casualties of battle, and that a considerable number of men are sill in the rear, some having dropped out on the march, and many dispersing and leaving yesterday during the fight. I think the efficiency of the corps, so far as it goes, good. To resist an attack in our present strong position I think they may be depended on, and I hope they will perform duty in case we make an attack, though I do not think their morale is as good for an offensive as a defensive movement.

One division of Sumner's corps had also been overpowered, and was a good deal scattered and demoralized. It was not deemed by its corps commander in proper condition to attack the enemy vigorously the next day.

Some of the new troops on the left, although many of them fought well during the battle and are entitled to great credit, were, at the close of the action, driven back and their morale impaired.

On the morning of the 18th, General Burnside requested me to send him another division to assist in holding his position on the other side of the Antietam, and to enable him to withdraw his corps if he should be attacked by a superior force. He gave me the impression that if he were attacked again that morning, he would not be able to make a very vigorous resistance. I visited his position early, determined to send General Morell's divisions to his aid, and directed that it should be placed on this side of the Antietam, in order that it might cover the retreat of his own corps from the other side of the Antietam should that become necessary, at the same time it was in position to re-enforce our center or right if that were needed.

Late in the afternoon I found that, although he had not been attacked, General Burnside had withdrawn his own corps to this side of the Antietam, and sent over Morell's division alone to hold the opposite side.

A large number of our heaviest and most efficient batteries had consumed all their ammunition on the 16th and 17th, and it was impossible to supply them until late on the following day. Supplies of provisions and forage had to be brought up and issued, and infantry ammunition distributed. Finally, re-enforcements to the number of 14,000 men, to say nothing of troops expected from pennsylvania, had not arrived, but were expected during the day.

The 18th was, therefore, spent in collecting the dispersed, giving rest to the fatigued, removing the wounded, burying the dead, and the necessary preparations for a renewal of the battle.

Of the re-enforcements, Couch's division, marching with commenda-