"The advance against Harrisburg was arrested by intelligence received from a scout on the night of the 28th, to the effect that the army of General Hooker had crossed the Potomac and was approaching the mountains. In the absence of the cavalry it was impossible to ascertain his intentions; but to deter him from advancing farther west and intercepting our communications with Virginia, it was determined to concentrate the army east of the mountains.
"The movement of the army preceding the battle of Gettysburg had been much embarrassed by the absence of the cavalry. As soon as it was known that the enemy had crossed into Maryland, orders were sent to the brigades of [B. H.] Robertson and [Wm. E.] Jones, which had been left to guard the passes of the Blue Ridge, to rejoin the army without delay, and it was expected that General Stuart, with the remainder of his command, would soon arrive. In the exercise of the discretion given him when Longstreet and Hill marched into Maryland, General Stuart determined to pass around the rear of the Federal army, with three brigades, and cross the Potomac between it and Washington, believing that by that route he would be able to place himself on our right flank in time to keep us properly advised of the enemy's movements. He marched from Salem on the night of June 24th, intending to pass west of Centreville, but found the enemy's forces so distributed as to render that route impracticable. Adhering to his original plan, he was forced to make a wide detour through Buckland and Brentsville, and crossed the Occoquan at Wolf Run Shoals on the morning of the 27th. Continuing his march through Fairfax Court House and Drainesville, he arrived at the Potomac below the mouth of Seneca Creek in the evening. He found the river much swollen by the recent rains, but after great exertion gained the Maryland shore, before midnight, with his whole command. He now ascertained that the whole Federal army, which he had discovered to be drawing towards the Potomac, had crossed the day before, and was moving towards Fredericktown, thus interposing itself between him and our forces.
"Robertson's and Jones's brigades arrived on July 3d, and were stationed upon our right flank. The severe loss sustained by the army, and the reduction of its ammunition, rendered another attempt to dislodge the enemy inadvisable, and it was therefore determined upon to withdraw."
[15 ]Stuart has been criticised for carrying into our lines a train of one hundred and twenty-five wagons, which he captured in Maryland, with supplies for Hooker, on account of the delay it produced in joining Gen. Lee. But the expedition has been condemned, not as an independent raid, but because it is said that it deprived Gen. Lee of his cavalry, which ought to have given him notice of Hooker's advance into Pennsylvania. But as Gen. Lee actually received notice of it on the very night that Stuart crossed the Potomac, it is hard to see what harm was done by taking the wagons with him. And I have shown that Stuart left with Gen. Lee sufficient cavalry to do the work of guarding his flank and observing the enemy.
[16 ] So far as keeping Gen. Lee informed of Hooker's movements is concerned, it was immaterial whether Stuart crossed east or west of the Ridge. In either event he would have been separated from Gen. Lee and unable to watch the line of the Potomac. Stuart was ordered to take three brigades to the Susquehanna and to leave two behind him to watch Hooker. He was simply given discretion as to the point of crossing the Potomac. He is not responsible for the division of his command.
[17 ] On June 22, 1863, 3.30 P.M. Gen. Lee, writing from Berryville, Va., to Ewell, who was then about Hagerstown, Md., says: "My letter of to-day, authorizing you to move toward the Susquehanna, I hope has reached you ere this. I have also directed Gen. Stuart, should the enemy have so far retired from his front as to permit of the departure of a portion of the cavalry, to march with three brigades across the Potomac, and place himself on your right and in communication with you, keep you advised of the movements of the enemy, and assist in collecting supplies for the army. I have not heard from him since." As Stuart was not ubiquitous, Gen. Lee must have relied on the cavalry left behind to do for him what he intended that Stuart should do for Ewell.
[18 ] [Telegram.] Maryland Heights, June 24, 1863. H. W. Halleck, General-in-Chief:— Longstreet's corps, which camped last between Berryville and Charlestown, is to-day in motion and before 6 O.C. this morning commenced crossing by the ford one mile below Shepherdstown to Sharpsburg. Gen. Tyler, Brigadier-General.