CHAPTER I.
THE INVASION OF THE NORTH.
An invasion of the North being considered as both practicable and necessary, it only remained to select the most available route.
There was no object in passing east of Hooker's army, and it would have been wholly impracticable to do so, as the wide rivers to be crossed were controlled by our gunboats.
To attempt to cross the Rappahannock to the west, and in the immediate vicinity of Fredericksburg, would have been hazardous, because when an army is crossing, the portion which is over is liable to be crushed before it can be reinforced.
It would seem that Lee's first intention was to move along the eastern base of the Blue Ridge directly toward Washington.* The appearance of his army on Hooker's flank would be a kind of taunt and threat, calculated to draw the latter out of his shell, and induce him to make an attack.

In such a case, as the rebels were in the highest spirits, in consequence of their recent victory at Chancellorsville, their commander had little doubt of the result.
This plan was feasible enough, provided his cavalry could beat back that of Pleasonton and act as a screen to conceal his movements.
This they were not in a condition to do after the battle of Brandy Station, and Lee was thus forced to take the route down the Shenandoah Valley, which had many advantages.

The mountain wall that intervened between the two armies, was a sure defence against our forces, for it was covered by dense thickets, and the roads that lead through the gaps, and the gaps themselves, were easy to fortify and hold against a superior force.

If Hooker had attempted to assail these positions, one corps could have held him in check, while the other two captured Washington.
[* See map facing page 1.] The movement also favored the subsistence of the troops, for the valley being a rich agricultural region, Lee was enabled to dispense with much of his transportation and feed his army off the country.
There was one serious obstacle, however, to his further progress in that direction, and that was the presence of a gallant soldier, Milroy, with a very considerable Union garrison intrenched at Winchester.
It was essential to Lee's advance that the valley should be cleared of Union troops, otherwise they would sally forth after he passed and capture his convoys.
With this object in view, on the 10th Ewell's corps passed through Gaines' Cross Roads, and halted near Flint Hill on their way to Chester Gap and Front Royal.
The possibility of an invasion had been discussed for some days in Washington, and Halleck had come to the conclusion that it was better to withdraw the stores and ammunition from Winchester, and retain the post there merely as a lookout, to give warning of the enemy's approach.

Accordingly, on the 11th, Milroy received orders from his department commander, General Schenck, to send his armament and supplies back to Harper's Ferry.