About 10 o'clock a.m. word was received that he had made a stand a mile or more in front of Sharpsburg, and about that distance from Richardson's command. As General Richardson was without artillery, he had borrowed a section from Pleasonton, and had already opened on the enemy when I reached the field. The rebels appeared to be ostentatiously deployed in two lines, perpendicular to the road leading to Sharpsburg, with his batteries posted to resist the passage of our forces over the bridge which crosses that stream. All of his troops appeared exposed to view, and numbered, as nearly as I could estimate, about 30,000 men. Fully conscious of my weakness in number and morale, I did not feel strong enough to attack him in front, even after the arrival of the First Corps, and it was only after the left of the enemy was observed to break into column and march to the rear, behind a forest, on which appeared to be the Williamsport road, that Major D. C. Houston, of the Engineers, was dispatched up the river to find practicable fords, by the means of which my troops might be thrown across the Antietam River to attack the enemy, and perhaps cut off his artillery, as soon as his numbers were sufficiently reduced to justify the movement. A bridge was found, and also two fords, which with little labor on the banks were rendered practicable for the passage of infantry and artillery. At 5 o' clock p.m. about one-half of the enemy's infantry force had passed to the rear, when I deemed it too late to make the detour, in order to come up with the enemy, without a night march through a country of which we were profoundly ignorant.
Meanwhile the bulk of the army was arriving in the valley of Antietam, and all the enemy's artillery, with a considerable portion of his infantry, remained in the position in which we had found them in the morning.
Between 1 and 2 o'clock the day following, I received instructions from the major-general commanding the Army of the Potomac to cross the river with the First Corps, and attack the enemy on his left flank, Meade's and Ricketts' divisions crossing the ridge near Keedysville, and Doubleday's division at the ford just below it.
As soon as I way my command under way, I rode to the headquarters of the commanding general for any further orders he might have to give me, when I was informed that I was at liberty to call for re-enforcements if I should need them, and that on their arrival they would be placed under my command, and I returned and joined my troops on their march. Our direction was nearly perpendicular to the river we had crossed, my object being to gain the high ground or divide between the Potomac and Antietam Rivers, and then incline to the left, following the elevation toward the left of the rebel army. Two regiments of Meade's division were thrown forward as skirmishers, followed by a squadron of Owen's cavalry, and all supported by Meade's division. We had not proceeded over a half a mile before the commanding general with his staff joined me, apparently to see how we were progressing. Among other subjects of conversation, I said to the general that he had ordered my small corps, now numbering between 12,000 and 13,000 (as I had just lost nearly 1,000 men in the battle of South Mountain), across the river to attack the whole rebel army, and that if re-enforcements were not forwarded promptly, or if another attack not made on the enemy's right, the rebels would eat me up. Pretty soon after this interview, my skirmishers became engaged with the enemy's advanced post, and the firing was continued incessantly until dark, we advancing slowly, and the enemy retiring before us. During the last part of the time the