They scarcely numbered 10,000 infantry, and McClellan
must have known that all the remainder of Lee
's army was concentrated about Harper's Ferry
He could never wish for a fairer chance to crush an adversary, but he did nothing that afternoon or the next morning.
During the 16th he was joined by the 9th corps, and at 7.30 P. M. he ordered two divisions of the 6th corps from Pleasant Valley
, under Franklin
, to join him next day, while the 3d division under Couch
was ordered to occupy Maryland Heights
; for what useful purpose it is hard to divine.
Meanwhile, his plan of battle had been formed.
It was to send the 1st, 2d, and 12th corps, over 30,000 men, across the Antietam
above the Confederate
lines, to turn their left flank, while the 9th corps under Burnside
, about 10,000, should attack their right at Burnside Bridge as soon as things looked favorable above.
The 5th and 6th corps, Porter
, would be in reserve opposite our centre with 31,339 infantry and artillery besides a considerable force of cavalry and horse artillery.
The plan was not a good one, involving as it did a piecemeal beginning.
The three corps to attack the Confederate
left should have been under one commander, and should have moved together.
Instead, the 1st corps, under Hooker
, was started about 2 P. M. on the 16th; the 12th corps, under Mansfield
, not until 11.30 P. M. The 2d corps, under Sumner
, was ordered to be ready to march an hour before daylight.
It was ready, but received no orders.
After daylight, the battle having opened and the firing become heavy, Sumner
rode to McClellan
's headquarters to ask for orders, and waited an hour or more without being able to see him. Orders to advance finally reached him at 7.30 A. M. The sun had risen at 5.45 and Hooker
had become engaged soon after daylight, probably about five o'clock. Sumner
had some distance to march, and was only able to get into action after 10 A. M. By this time, as we shall see, Hooker
had been wrecked, and Sumner
's wreck soon followed.
formed his line on the 16th, Jackson
's two divisions held the left, between the Hagerstown pike
's cavalry, which held a road nearer the river.
's two brigades had their left upon the pike, and on their right D. H. Hill