WAR DEPARTMENT, Washington City, August 5, 1862.

Major-General McCLELLAN, Berkeley:

I have no re-enforcements to send you.

H. W. HALLECK,

General-in-Chief.

HEADQUARTERS SEVENTH ARMY CORPS, Fort Monroe, Va., August 6, 1862.

Brigadier General R. B. MARCY,
Chief of Staff;

GENERAL: I received your letter of the 4th yesterday, instructing me to send a command to level embankments on the James River. Commodore Wilkes has taken upon himself to ascertain and advise me where these embankments are. I do not understand whether you allude to the north as well as the south bank of the river.

The difficulty will be to get a command to do the work. I have no force whatever which I can use unless I withdraw a regiment or two from Suffolk, and from recent indications I think this would be very hazardous.

The enemy's force on the Blackwater has been strengthened, and General Mansfield has been asking for re-enforcements. I can spare nothing from Williamsburg or Yorktown, and here I have for the fort only 500 men, and at Camp Hamilton only 600 men fit for duty, to do all the guard service for the hospitals, now greatly extended.

Commodore Wilkes will see you to-morrow morning, and I ask the further directions of the commanding general.

I am, very respectfully, yours,

JOHN A. DIX,

Major-General.

HEADQUARTERS OF THE ARMY, Washington, August 7, 1862.

Major-General McCLELLAN, Berkeley:

MY DEAR GENERAL: Your private letter of the 1st instant was received a day or two ago, but I have been too busy to answer it sooner.

If you still wish it I will order Barnard here, but I cannot give you another engineer officer unless you take Benham, for you already have a larger proportion than any one else. I had, most of the time, out West only two, and you, with no larger force, have a dozen engineer officers.

I fully agree with you in regard to the manner in which the war should be conducted, and I believe the present policy of the President to be conservative.

I think some of General Pope's orders very injudicious, and have so advised him; but as I understand they were shown to the President before they were issued I felt unwilling to ask him to countermand them. An oath of allegiance taken through force is not binding, and to put over the lines those who do not take it is only adding numbers to the rebel army. What he has made the general rule should be only the exception, and I have so advised him.

I deeply regret that you cannot agree with me as to the necessity of