Thus, in this sequence of withdrawals, it will be seen that after Schenck and Reynolds had gotten in position to strike Jackson’s right, although too late to do so without danger of Longstreet’s advance falling upon their flank, Schenck sent off Stahel’s brigade at Milroy’s calls. Reynolds then moved back, because Schenck had retired and left him unsupported, as he supposed, and also because his left was threatened by Longstreet’s advance; and Schenck in turn moved back because Reynolds had withdrawn, although the latter had only refused his line, which, situated in open ground with the enemy in force in his front, was the right thing for him to do.
Our guns at Groveton could see along and flank the front of the Union line on the right as far as the railroad, and their thunder encouraged the troops on that wing, and deterred the enemy from aggressive movements which would subject them to an enfilade fire of artillery. The position was in truth a key-point, not only commanding the lower ground to the right, but also affording good ground upon which to receive an attack, or from which to advance, and, moreover, it covered the roads southward, by which Porter’s troops, as will be seen presently, were expected to join the army.
The drawing back of our guns and troops from Groveton was the signal for Jackson’s lines to push forward more aggressively. Milroy was roughly handled and forced back. It was General Stevens’s third brigade, under Colonel Addison Farnsworth, that was sent to support Schurz, and was posted on the front line along the railroad, next to Schimmelfennig’s brigade. Part of this brigade, on Farnsworth’s left, broke at the advance of the enemy, and fell back through the woods, but the Highlanders and Faugh-a-ballaghs stood firm and repulsed the attack. Soon afterwards the fugitives, having reformed, moved up in line from the rear, and began firing into the backs of the troops who had stood their ground, mistaking them for the enemy; but this was speedily stopped, and they were again placed on the line.
The experience of the first brigade was equally unsatisfactory. Placed in the first line, they were left to bear the brunt of the fighting on Milroy’s front, and were finally obliged to fall back by the giving way of troops on their flanks.
General Pope arrived on the field about noon, and made his headquarters in rear of the Sudley road, near Buck Hill. Although he declares in his report that he refused Sigel’s demands for reinforcements, it is clear beyond doubt that he neither put a stop to the wasteful scattering of his best troops, nor attempted to unite and bring them together as a disposable force of weight for offensive movements. All the afternoon he was expecting Porter’s and McDowell’s column to fall upon Jackson’s right and rear, for he had worked himself up to the belief that Longstreet would not be up for another day, and nothing short of disastrous defeat could shake his dogged belief.
On receiving news of King’s and Ricketts’s retreat from Gainesville and Groveton, which he did about daylight, General Pope ordered Porter to march upon Gainesville with his own corps and King’s division. “I am following the enemy down the Warrenton turnpike,” he adds. “Be expeditious, or we will lose much.” And later he dispatched a joint order to McDowell and Porter to the same effect:—
“You will please move forward with your joint commands toward Gainesville.... Heintzelman, Sigel, and Reno are moving on the Warrenton turnpike, and must now be not far from Gainesville. I desire that as soon as communication is established between this force and your own, the whole command shall halt.... One thing must be had in view, that the troops must occupy a position from which they can reach Bull Run to-night or by daylight.”
Porter had already passed Manassas on his way to Centreville when he received the first order, but immediately countermarched to the Junction and towards Gainesville as ordered, with Morell’s division leading, Sykes’s next, then Piatt’s brigade, and King following in rear. About eleven o’clock the head of the column reached Dawkins Branch, an insignificant brook four and a half miles from Gainesville, and two and a half miles south of Groveton. Here the enemy was perceived, and skirmishers were thrown across the creek, supported by Butterfield’s brigade; and Porter was forming to advance on the enemy, when General McDowell joined him, and showed a dispatch from Buford as follows:—
“Headquarters Cavalry Brigade, 9.30 A.M. Seventeen regiments, one battery, and five hundred cavalry passed through Gainesville three quarters of an hour ago on the Centreville road.”
The presence of the enemy in front, and clouds of dust rising along the roads in his rear, corroborated this dispatch. So, too, did the noise of the artillery combat at Groveton. The two generals rode together through the woods to the right as far as the Manassas Gap Railroad, but decided that it was “impracticable” to move northward a mile and a half across country to effect a junction with the right wing. McDowell then left Porter, telling him that he would take King’s division around by the Sudley road and put it in between Porter and the right wing. Except for some slight changes in position of the head of his column, Porter remained inactive the rest of the day, with his rear stretching back two and a half miles along the road. What befell King’s division, under McDowell’s guidance, will be seen later. Unquestionably, Longstreet was up and in position in time to resist the attack of McDowell and Porter, had they made one. And a board of three officers of great reputation and experience,—Generals Schofield, Terry, and Getty,—after a thorough examination, has declared that such an attack would have been ill advised, has applauded Porter’s conduct, and pronounced the opinion that his presence there that day saved the army from disaster.