preparations were made to advance upon Harrisburg, but on the night of the 28th, information was received from a scout, that the Federal Army, having crossed the Potomac, was advancing northward, and that the head of the column had reached South Mountain &c.
In General Longstreet's official report he makes a similar statement: "That on the night of the 28th, one of the scouts came in with the information, that the enemy had passed the Potomac, and was probably in pursuit of us," and his book, "From Manassas to Appomattox," the scout is described as one who had been employed by him, and that he brought the additional intelligence of Meade's assignment to the command of the Federal army. Colonel Mosby has pointed out the extreme improbability, or as he thinks impossibility, that the scout referred to could have brought the news of Meade's assignment.
The messenger conveying the order of assignment did not reach Frederick until the morning of the 28th, and the order would not be promulgated and become known generally among the troops, so that it could be picked up by a spy until probably late in the day, when it would be next to impossible for a scout in the Federal camps at Frederick to reach Longstreet at Chambersburg the same night. It would appear too, notwithstanding the language of both these official reports, that General Lee must have had some knowledge of Hooker's movements prior to the news brought in by the scout on the night of the 28th. For in his letter to General Ewell, dated June 28, 1863, 7:30 A. M., from Chambersburg, he says, "I wrote you last night stating that General Hooker was reported to have crossed the Potomac, and is advancing by way of Middletown," &c. He adds, "That in that letter he had directed him to return to Chambersburg, or if there were any reason against it, to proceed in the direction of Gettysburg." The information, then, which reached General Lee on the 28th must have been that the column had reached South Mountain and not that it had crossed the Potomac. That it had reached South Mountain, and that up to this time, he had not heard a word from Stuart, doubtless surprised and disturbed him. Two cavalry brigades of Jones and Robertson, which had been left behind on the Potomac, and who were to receive their orders
