want of ammunition, was in little condition to make long resistance, I sent back orders to General Porter, about dark of the 27th, to move forward at 1 o'clock in the night and report to me at Bristoe by day-light in the morning, leaving instructions in some detail for Banks, who was expected at Warrenton Junction during that night or early in the morning. The orders for all these movements are herewith appended. General Porter failed utterly to obey the orders that were sent him, giving as an excuse that his men were tired, that they would straggle in the night, and that the wagon trains proceeding eastward, in the rear of Hooker's division, would offer obstructions to his march. He, however, made no attempt whatever to comply with this order, although it was stated to him in the order itself that his presence was necessary on all accounts at daylight, and that the officer delivering the dispatch was instructed to conduct him to the field.

There were but two courses left open to Jackson in consequence of this sudden and unexpected movement of the army: He could not retrace his steps through Gainesville, as it was occupied by McDowell, having at command a force equal, if not superior, to his own, and was either obliged, therefore, to retreat through Centreville, which would carry him still farther from the main body of Lee's army, or to mass his force, assault us at Bristoe Station, and turn our right. He pursued the former course, and retired through Centreville. This mistake of Jackson's alone saved us from the consequences which would have followed this flagrant and inexcusable disobedience of orders on the part of General Porter.

At 9 o'clock on the night of the 27th, satisfied of Jackson's position, I sent orders to General McDowell to push forward at the very earliest dawn of day toward Manassas Junction from Gainesville, resting his right on the Manassas Gap Railroad and throwing his left well to the east. I directed General Reno to march at the same hour from Greenwich direct upon Manassas Junction, and Kearny to march at the same hour upon Bristoe. This latter order was sent to Kearny to render my right at Bristoe perfectly secure against the probable movement of Jackson in that direction. Kearny arrived at Bristoe about 8 o'clock in the morning, Reno being on his left and marching direct upon Manassas Junction. I immediately pushed Kearny forward in pursuit of Ewell toward Manassas, followed by Hooker. General Porter's corps did not arrive at Bristoe until 10.30 o'clock in the morning, and the moment he found that Jackson had evacuated Manassas Junction he requested permission to halt at Bristoe and rest his men. Sykes' division, of Porter's corps, had spent the whole day of the 27th, from 10 o'clock in the morning until daylight of the 28th, in camp at Warrenton Junction. Morel's division, of the same corps, had arrived at Warrenton Junction during the day of the 27th, and also remained there during the whole of that night. Porter's corps was by far the freshest in the whole army, and should have been, and I believe was, in better condition for service than any troops we had. General McDowell reported to me afterward that he had given orders for the movement of his command upon Manassas Junction at 2 o'clock at night, in accordance with the directions I had sent him, but General Sigel, who commanded his advance and was at Gainesville, instead of moving forward from Gainesville at daylight, as he was ordered, was absolutely with his advance in that town as late as 7.30 o'clock in the morning. Meantime, beginning about 3 o'clock in the morning of the 28th, Jackson commenced evacuating Manassas Junction, and his troops were marching from that point in the direction of Centreville until 10 or 11