The army corps of General McDowell's about 19,000 strong, is by far the best, and in fact the only reliable portion of my command. One division is at Manassas, the other at Fredericksburg.

General Sturgis in command of the forces within and outside of the intrenchments near Washington. They number altogether about 17,000 men, mostly raw recruits and fragments of broken regiments, in no condition for service.

My first object is to concentrate all these forces (except those under Sturgis), as far as practicable, in advance of this place, both to put them in condition for active operations and to have them in hand. In this arrangement the security of the valley of the Shenandoah and of the city of Washington must be held in view. I have therefore broken up the depots on the Ohio River and on the Baltimore and Ohio Railroad, and established my depots and base of operations at Alexandria. I am concentrating the two corps of Fremont (now Sigel's) and Banks near Luray Gap)Sperryville); Banks' about 5 or 6 miles east of that place.

The division of McDowell, now at Manassas, has moved forward to Warrenton and taken post. His cavalry brigade has advanced to Warrenton Junction, with strong cavalry pickets south of the Rappahannock. The division at Fredericksburg pickets the country 20 miles in advance of that place. A good stone turnpike connects Luray with Warrenton. It was my purpose, before the news of your critical situation reached here, to concentrate the two divisions of McDowell at Orange Court-House and the corps of Banks and Sigel at Stanardville; thence to occupy Gordonsville long enough to destroy entirely the Virginia Central road between that place and Hanover Court-House, and to move on Charlottesville, or a point east of that place, with my whole force united; to destroy the railroad between Lynchburg and Charlotesville, and also, by pushing cavalry in various directions toward it, to destroy the railroad from Lynchburg to Richmond; to move down to James River at Columbia, and to pursue the north (left) bank of the river toward Richmond at least as far as Tuckahoe Creek; to take up a strong position behind that creek, and throw bridges over the James River or secure those now existing within the proposed lines, so as to be able to throw my whole force across to the south side whenever it became necessary. Having secured these objects, to aid you in any way in the immediate operations against Richmond.

The occurrences of the last few days have deranged this plan, and I am holding my forces at the points I have designated, so as to be able, by marching rapidly on Gordonsville and Charlottesville, to cut off any force which may penetrate into the valley of the Shenandoah from the direction of Richmond, and at the same time be able to concentrate my whole force with little delay in front of Washington in case of necessity. These positions I shall hold until some well-defined plan of operations and co-operations can be determined on.

It seems to me that it will not be difficult for the enemy at Richmond to detach 50,000 men to march rapidly on Washington if it be uncovered by the movement of the for under my command in any direction. Much of my cavalry I am keeping in the valley of the Shenandoah, and as soon as my forces are established as I have designated, they (the cavalry) will be pushed as far south as Swift Run Gap and Harrisonburg. I have intrenched a brigade of infantry with one battery at Winchester; a somewhat smaller force will be posted in a like manner at Romney. The small posts at Clarksburg, Beverly Buckhannon, &c., are placed under charge of General Kelley, who has some