the night of the 27th, the whole of the Federal army was also in Maryland, and communication with General Lee was cut off; for, as Mosby says, Pleasanton's cavalry, which was the rear guard of the Federal army, crossed the Potomac at Edwards' Ferry at the same time that General Stuart crossed at Seneca. Ewell was by that time at Carlisle, and Longstreet's and Hill's corps were also in Pennsylvania at Chambersburg, having, as General Lee says, advanced so far without any report that the Federal army had crossed the Potomac.
General Lee says in his second report that General Stuart was directed to lose no time in placing his command on the right of our column as soon as he perceived the enemy moving northward. He might have said that Stuart was authorized to cross the Potomac and join with Ewell in his advance without waiting for the enemy to move northward; for Swell's right was the place assigned to him at the time Swell's advance was ordered. There was no uncertainty about his instructions to take position on Swell's right and guard his flank, for they were reiterated whether he crossed the Potomac at Shepherdstown, as General Lee suggested, or elsewhere. That was the essential point of his instructions, and General Lee had the right to expect that they would be carried out.
Stuart knew he was expected to be on Swell's right and intended to be there. His report as published by Col. Mosby, states the causes of his delay in getting into position, (pages 176, 177 and 178):
"Accordingly, three days rations were prepared and on the night of the 24th, the following brigades Hampton's, Fitz Lee's and W. H. F. Lee's rendezvoused secretly near Salem Depot. * * At one o'clock at night the brigades, with noiseless march, moved out. * * Moving to the right we passed through Glasscock's Gap without difficulty and marched for Haymarket. * * As we neared Haymarket, we found Hancock's corps en route through Haymarket for Gum Springs, his infantry well distributed through his trains. I chose a good position and opened with artillery on his passing column with effect, scattering men, wagons and horses in wild confusion; disabled one of the enemy's caissons,