IT is generally agreed by Southern writers that the battle of Gettysburg was the result of an accidental collision of armies. General Lee in effect says in his report of the campaign that his failure was due to his ignorance of the movements of the enemy; and the absence of a portion of the cavalry under Stuart, or rather its separation from the army, is assigned as the primary cause of its failure by General Long, the biographer of Lee, and by General Longstreet. Both ignore the fact that Stuart left with General Lee, under command of General Beverly H. Robertson, a larger body of cavalry than he took with him. General Long charges that Stuart's expedition around Hooker was made either from "a misapprehension of orders or love of the eclat of a bold raid" (which, of course, implies disobedience); and General Longstreet, while admitting that Stuart may have acted by authority of Lee, says that it was undertaken against his own orders, which were to cross the Potomac at Shepherdstown, west of the Blue Ridge.

That General Lee was greatly embarrassed by want of intelligence of the movements of the enemy was not due to the lack of cavalry; and Stuart is not responsible for the inefficient manner in which Lee was served. When it was determined that Stuart should take three brigades of cavalry to join Ewell on the Susquehanna and leave his other two to perform outpost duty for the army in Virginia, General Lee was in the Shenandoah Valley with the corps of Hill and Longstreet. The latter was holding the gaps and Stuart was guarding the approaches to them east of the ridge. Hence Stuart came under Longstreet's orders. Hooker's headquarters were in Fairfax, with his army spread out like a fan -- his left being at Thoroughfare Gap and his right on the Potomac at Leesburg. On returning from a scout, I reported to Stuart the scattered condition of Hooker's corps, and he determined, with the approval of General Lee, to pass around, or rather through, them, as the shortest route to Ewell. There was an opportunity besides to inflict much damage and to cut off communication between Washington and the North.

I have lately discovered documents in the archives of the War Department that set at rest the question of Stuart's alleged disobedience of orders, and show that General Longstreet then approved a plan which he now condemns as "a wild ride around the Federal army." He directed Stuart to pass around the rear of the enemy in preference to crossing west of the ridge, in order to prevent disclosing our designs. (note)

Under date of June 22d, 7:30 P. M., he writes to General Lee: "I have forwarded your letter to General Stuart, with the suggestion that he pass by the enemy's rear if he thinks he may get through."

Up to the morning of June 25th it was perfectly practicable for Stuart to have done so. In accordance with Lee's and Longstreet's instructions Stuart withdrew from the front on the evening of the 24th to pass around Hooker, leaving Robertson about Middleburg with 3000 cavalry and 2 batteries of artillery to observe the enemy. Stuart's success depended upon preserving the status quo of the Federal army until he could get through it. Hooker was on the defensive waiting for his adversary to move. It did not seem to occur to General Longstreet that the march of the infantry down the Shenandoah Valley would disclose all to the enemy that the cavalry would have done. It was no fault of Stuart's that he was foiled by events which he could not control. When on the morning of the 25th he reached Hooker's rear, he found his whole army moving to the Potomac and all the roads occupied by his troops. This compelled a wide detour, and instead of crossing the river in advance of the enemy, as he had expected, he was two days behind him. Thus all communication was broken with Generals Lee and Ewell. The march of Hill's and Longstreet's corps on the day before had been in full view of the signal stations on Maryland Heights and was telegraphed to Hooker, who made a corresponding movement.

On the morning of June 26th the enemy disappeared from Robertson's front and crossed the Potomac. In that event his instructions from Stuart were, "to watch the enemy and harass his rear -- to cross the Potomac and follow the army, keeping on its right and rear," and to "report anything of importance to Lieutenant-General Longstreet, with whose position you will communicate by relays through Charlestown."

Robertson retired to the mountain gaps and remained until the afternoon of the 29th, when he was recalled to the army by a courier from General Lee. At night on the 28th General Lee heard, through a scout at Chambersburg, of Hooker's advance. As no information of it had come from the cavalry he had left in Hooker's front in Virginia, he thought that Hooker was still there. He immediately issued an order for the concentration at Gettysburg, and sent for Robertson's command, that had been left, he says, to hold the mountain passes, "as long as the enemy remained south of the Potomac." It had staid there three days after they had gone. As Stuart had been ordered to Ewell on the Susquehanna, it could not have been expected that he should also watch Hooker on the Potomac. Stuart's instructions to divide the cavalry and take three brigades with him to Ewell, on the Susquehanna, were peremptory; he was only given discretion as to the point of crossing the Potomac. It was therefore immaterial, so far as giving information to Lee was concerned, whether he crossed east or west of the ridge. In either event they would have been separated and out of communication with each other. Lee must then have relied on Robertson or nobody to watch Hooker.

Instead of keeping on the right of the army and in close contact with the enemy, as Stuart had ordered, Robertson's command marched on the left by Martinsburg and did not reach the battle-field. The rear-guard of the Federal army moving into Pennsylvania crossed the Potomac on June 26th, east of the Blue Ridge; Robertson crossed at Williamsport, about twenty-five miles to the west of it, on July 1st, the day the fighting began at Gettysburg. When General Lee crossed the Potomac, he left General Robertson between him and the enemy. By July 3d Robertson had so manoeuvred that Lee was between him and the enemy. Stuart had ridden around General Hooker while Robertson was riding around General Lee. If, in accordance with Stuart's instructions, Robertson had promptly followed on the right of the army when the enemy left, Lee's forces would have been concentrated and ready for attack; a defensive battle would have been fought, and Gettysburg might have been to Southern hearts something more than a

"Glorious field of grief."

WASHINGTON, Feb. 9th, 1887.

"HEADQUARTERS, MILLWOOD, June 22d, 1863, 7 P. M. MAJOR-GENERAL J. E. B. STUART, Commanding Cavalry. GENERAL: General Lee has inclosed to me this letter for you to be forwarded to you provided you can be spared from my front, and provided I think you can move across the Potomac without disclosing our plans. He speaks of your leaving via Hopewell Gap and passing by the rear of the enemy. If you can get through by that route, I think that you will be less likely to indicate what our plans are than if you should cross by passing to our rear. I forward the letter of instructions with these suggestions. Please advise me of the condition of affairs before you leave, and order General Hampton — whom I suppose you will leave here in command — to report to me at Millwood either by letter or in person, as may be most agreeable to him. Most respectfully, J. LONGSTREET, Lieutenant-General.— N. B. I think that your passage of the Potomac by our rear at the present moment will in a measure disclose our plans. You had better not leave us, therefore, unless you can take the proposed route in rear of the enemy. J. LONGSTREET, Lieutenant-General."

"HEADQUARTERS, 22d June, 1863. MAJOR-GENERAL J. E. B. STUART, Commanding Cavalry. GENERAL : I have just received your note of 7:45 this morning to General Longstreet. I judge the efforts of the enemy yesterday were to arrest our progress and ascertain our whereabouts. Perhaps he is satisfied. Do you know where he is and what he is doing? I fear he will steal a march on us and get across the Potomac before we are aware.

If you find that he is moving northward, and that two brigades can guard the Blue Ridge and take care of your rear, you can move with the other three into Maryland and take position on General Ewell's right, place yourself in communication with him, guard his flank and keep him informed of the enemy's movements, and collect all the supplies you can for the use of the army. One column of General Ewell's army will probably move toward the Susquehanua by the Emmitsburg route, another by Chambersburg Accounts from him last night state that there was no enemy west of Fredericktown. A cavalry force (about one hundred) guarded the Monocacy bridge, which was barricaded. You will, of course, take charge of Jenkins's brigade and give him necessary instructions. All supplies taken in Maryland must be by authorized staff-officers for their respective departments, by no one else. They will be paid for or receipts for the same given to the owners. I will send you a general order on this subject, which I wish you to see is strictly complied with. I am, very respectfully, your obedient servant, E. E. LEE, General."

On the following day General Lee wrote as follows:

"HEADQUARTERS, ARMY OF NORTHERN VIRGINIA, June 23d, 1863, 5 P. M. MAJOR-GENERAL J. E. B. STUART, Commanding Cavalry. GENERAL: Your notes of 9 and 10:30 A. M. to-day have just been received. . . . If General Hooker's army remains inactive you can leave two brigades to watch him and withdraw with the three others, but should he not appear to be moving northward, I think you had better withdraw this side of the mountain to-morrow night, cross at Shepherdstown next day, and move over to Fredericktown. You will, however, be able to judge whether you can pass around their army without hindrance, doing them all the damage you can, and cross the river east of the mountains In either case, after crossing the river, you must move on and feel the right of Swell's troops, collecting information, provisions, etc. Give instructions to the commander of the brigades left behind to watch the flank and rear of the army and (in event of the enemy leaving their front) retire from the mountains west of the Shenandoah, leaving sufficient pickets to guard the passes, and bringing everything clean along the valley, closing upon the rear of the army. As regards the movements of the two brigades of the enemy moving toward Warrenton, the commander of the brigades to be left in the mountains must do what he can to counteract them; but T think the sooner you cross into Maryland, after to-morrow, the better. The movements of Ewell's corps are as stated in my former letter. Hill's first division will reach the Potomac today, and Longstreet will follow to-morrow. Be watchful and circumspect in all your movements. I am very respectfully and truly yours, R E. LEE, General."—J. S. M.