and the imaginary dangers vanished only with the appearance of General Wright, who, with the Sixth Corps and one division of the Nineteenth Corps, pushed out to attack Early as soon as he could get his arriving troops in hand, but under circumstances that precluded celerity of movement; and as a consequence the Confederates escaped with little injury, retiring across the Potomac to Leesburg, unharassed save by some Union cavalry that had been sent out into Loudoun County by Hunter, who in the meantime had arrived at Harper’s Ferry by the Baltimore and Ohio railroad.  From Leesburg Early retired through Winchester toward Strasburg, but when the head of his column reached this place he found that he was being followed by General Crook with the combined troops of Hunter and Sigel only, Wright having returned to Washington under orders to rejoin Meade at Petersburg.  This reduction of the pursuing force tempting Early to resume the offensive, he attacked Crook at Kernstown, and succeeded in administering such a check as to necessitate this general’s retreat to Martinsburg, and finally to Harper’s Ferry.  Crook’s withdrawal restored to Early the line of the upper Potomac, so, recrossing this stream, he advanced again into Maryland, and sending McCausland on to Chambersburg, Pennsylvania, laid that town in ashes, leaving three thousand non-combatants without shelter or food.

When Early fell back from the vicinity of Washington toward Strasburg, General Grant believed that he would rejoin Lee, but later manoeuvres of the enemy indicated that Early had given up this idea, if he ever, entertained it, and intended to remain in the valley, since it would furnish Lee and himself with subsistence, and also afford renewed opportunities for threatening Washington.  Indeed, the possession of the Valley of the Shenandoah at this time was of vast importance to Lee’s army, and on every hand there were indications that the Confederate Government wished to hold it at least until after the crops could be gathered in to their depots at Lynchburg and Richmond.  Its retention, besides being of great advantage in the matter of supplies, would also be a menace to the North difficult for General Grant to explain, and thereby add an element of considerable benefit to the Confederate cause; so when Early’s troops again appeared at Martinsburg it was necessary for General Grant to confront them with a force strong enough to put an end to incursions north of the Potomac, which hitherto had always led to National discomfiture at some critical juncture, by turning our army in eastern Virginia from its chief purpose—­the destruction of Lee and the capture of the Confederate capital.