HDQRS. DEPT. OF VIRGINIA, SEVENTH ARMY CORPS, Fort Monroe, Va., April 23, 1863.

General H . W . HALLECK,
General-in-Chief:

GENERAL: In my telegraphic dispatch of the 18th I said that I had been long in favor of occupying West Point. I should have taken possession of it if I had been able to spare 5,000 men, the smallest number requisite to make the occupation secure. My object was to cut off Gloucester and Matthews Counties as sources of supply to the insurgents, and from the Piankatank River and the mouth of the Rappahannock. In your letter of the 17th instant you suggest the occupation of that position as a base for a movement in support of General Hooker, who I suppose is to move on Richmond from Fredericksburg . I have no doubt that it would be advisable if I could have a sufficient force. The White House would be a still better position, as it is 20 miles near the enemy's flank, but portions of the Pamunkey River are narrow, and the water communications might be interrupted or made insecure by batteries planted on its banks. Should the enemy withdraw from Suffolk I will occupy West Point with all the force I can spare.

I agree with you that a movement on Weldon would be hazardous, and it would be of little advantage unless we could go there in sufficient force to hold it. The destruction of the railroad bridge at Goldsborough, which cost us many lives, only interrupted the communication for about thirty days, a temporary inconvenience but not a serious disaster or the enemy. Our great error has been in occupying too many positions. There was an excuse for scattering our forces while there was reason to believe that the people of the South would rally around them as nucleus for the restoration of the Union. This hope is now gone, and as our only chance of success is by overpowering them by preponderance of force or wearing them out by cutting off their commerce with foreign countries, all interior positions, unless they have some special importance, should be abandoned.

In this department no useless positions are occupied. There are but two points of great importance--Fort Monroe and Norfolk--the former as a military position commanding the Chesapeake Bay and the rivers that enter into it, and the latter as a naval station for the repair of our gunboats and transports, which would otherwise be obliged to go to Baltimore or Washington on the occurrence of any ordinary casualty. Suffolk was occupied partly to cover Norfolk and partly in pursuance of the purpose, already referred to, of affording to the people a rallying point for the restoration of the Union. In the latter respect it has failed, and in view of the former there is a better position--the line of the Deep Creek and the West Branch of Elizabeth River--more defensible, and from which an army could retire on Norfolk with ease and safety. I am preparing to fortify it. Suffolk is weak from the long and narrow channel of the Nansemond, running 7 miles to the rear, with an average width of less than 100 yards. It requires a large force and incessant vigilance to prevent the enemy from crossing and cutting off our communications with Norfolk. But as it wold be impossible to fall back on that city in the face of a superior force it must be held at all hazards.

Yorktown is occupied to keep the enemy at a distance from this post. He would not be likely to pass it while held by us. If it were aban-