All of Ewell's corps were across the river on the 22d, and Jenkins' cavalry pushed on to Chambersburg. He was ordered to remain there until reinforced, but failed to do so, as Union troops were approaching from the direction of Carlisle.
Longstreet and Hill were left behind to prevent Hooker from striking the rear of this long column. Hooker still remained quiescent, engaged in trying to obtain 15,000 men as reinforcements. He was but partially successful, for as soon as the New York regiments reached Baltimore, Lockwood's brigade of Maryland troops, about three thousand, was ordered to join the Army of the Potomac, and was assigned to the Twelfth Corps.
The Army of the Potomac at this time was posted as follows: The Twelfth Corps at Leesburg, supported by the Eleventh on Goose Creek, between Leesburg and Aldie; the Fifth Corps near Aldie, and the Second at the next pass below, both supported by the Third Corps at Gum Springs. The First Corps was behind the Eleventh and Twelfth Corps, near Guilford, on the Loudon and Hampshire Railroad. Our cavalry, which had left Aldie, covered the approaches to Leesburg. On the 23d they had a sharp engagement at Dover, on the road from Aldie to Leesburg, with part of Stuart's force, who beat up their quarters, but they drove off their assailants without much difficulty.
Lee now, with a prudent regard to a possible defeat, requested the authorities at Richmond to have a reserve army under Beauregard assemble at Culpeper; a request which was looked upon by Davis as one quite impossible to carry out, owing to the scarcity of troops, and the necessity of reinforcing Johnston in the West and Beauregard in the South.
Two of Ewell's divisions, those of Rodes and Johnson, reached the frightened town of Chambersburg on the 23d. The other, under Early, took the road to York, via Gettysburg, and halted on that day at Waynesborough.
By this time twenty regiments of militia were on their way from
New York to Baltimore and Harrisburg.
Longstreet crossed the Potomac at Williamsport, and Hill at Shepherdstown, on the 24th. Their columns united at Hagerstown the next day. Thus supported, Ewell's main body resumed its march to Carlisle, which it occupied on the 27th; gathering large supplies there and along the road by means of foraging parties sent out to depredate on the farmers. As soon as they reached the town, Jenkins' brigade left for Harrisburg.
Hooker having now satisfied himself that the Capital was safe from a coup-de-main, and that the main body of the rebels were still marching up the Cumberland Valley, determined to move in a parallel line on the east side of South Mountain, where he could occupy the gaps at once, in case the enemy turned east, toward Washington and Baltimore. To carry out this design his army began to cross the Potomac at Edwards' Ferry on the 25th, and at night Reynolds' corps was in front and Sickles' corps in rear of Middletown, in readiness to hold either Crampton's or Turner's Gap. Howard's corps was thrown forward to Boonsborough.
On the 26th Slocum's corps was sent to Harper's Ferry to act in conjunction with the garrison there—supposed to be 10,000 strong —against the enemy's line of communication with Richmond. The Second, Fifth, and Sixth Corps were advanced to Frederick, Md., as a support to the First, Third, and Eleventh Corps. Gregg's cavalry division remained behind to cover the crossing, which was all completed the next day, after which they too marched to Frederick.
On the 25th, Early, leaving his division at Greenwood, went to Chambersburg to consult Ewell, who gave him definite orders to occupy York, break up the Central Railroad, burn the bridge over the Susquehanna at Wrightsville, and afterward rejoin the main body at Carlisle.