is reported to have appeared to fill up the whole of Pennsylvania and leave no room for the inhabitants. Since we were not allowed to cross and whip A. P. Hill, while Longstreet and Ewell were moving off through Culpeper and Sperryville, we have lost the opportunity of doing a thing which we knew to a certainty we could accomplish. My impression now is that there is not a rebel, excepting scouts, this side of the Shenandoah Valley; that Lee is in as much uncertainty as to our whereabouts and what we are doing as we are as to his; that his movement on the Upper Potomac is a cover for a cavalry raid on the north side of the river, and a movement of his troops farther west, where he can turn up at some weak spot. Our signal dispatches about gunboats, fleets, transports, troops landing at Urbana, Rappahannock, making junction with Dix, disabled transports to go to Fort Monroe, pontoon bridges to Port Royal, and column to march down the Neck, which we kept up- systematically for a week or so to occupy their signal officers, may have fooled them into the belief, together with Dix's movements, that we were going to cross the Rappahannock down there, and he may be trotting back some of his force. Our scouts to-night will be in Fredericksburg, Culpeper, Warrenton, Salem, and one on the way in from Richmond. Those sent up to Western Maryland cannot get there before to-morrow night. We cannot go boggling round until we know what we are going after. Get any news you can that you know is definite a reliable, and bring out with you. Will they cashier any of these people who send in such stampeding reports? Bring me out a haversack or satchel for carrying maps on the march.

DANL. BUTTERFIELD,

Major-General, Chief of Staff.

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JUNE 17, 1863.

Major-General STAHEL,

Fairfax Court-House:

Can you send two regiments of cavalry to go to Warrenton and Sulphur Springs, and from there by scouts to penetrate through beyond, and ascertain what there is in that direction? Please answer, and say when they will be able to start. I will send you by orderly position of our troops to-night.

DANL. BUTTERFIELD,

Major-General, Chief of Staff.

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FAIRFAX COURT-HOUSE,

June 17, 1863-8. 50 p. m.

Major-General BUTTERFIELD,

Chief of Staff, Army of the Potomac:

Colonel De Forest, who is in command of the two regiments, has just arrived, and will report in person to you. His command will go by way of Centreville.

Respectfully,

JUL. STAHEL,

Major-General.

P. S. - Please notify me when you move your headquarters.