HEADQUARTERS ARMY OF THE POTOMAC,
Camp near Alexandria, August 31, 1862-12.15 p.m.

(Received 12.20 p.m.)

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

Captain Dana, assistant quartermaster, has 1,500 horses, intended for General Pope's army, and declines issuing from them to supply deficiencies in the batteries and cavalry I am sending to General Pope. I recommend that he be ordered at once to fill all requisitions made upon him for the batteries and cavalry formerly belonging to the Army of the Potomac and now sent to General Pope.

GEO. B. McCLELLAN,

Major-General.

WAR DEPARTMENT,

Washington, D. C., August 31, 1862-2.20 p.m.

Major-General McCLELLAN, Alexandria:

I meant by my telegram that Gregg's cavalry should be divided into two scouts, one to move up the river above Washington and the other toward Vienna, taking care to regulate the trains on the roads as they passed along. The latter part was only a suggestion. Use Captain Dana's horses as you may deem best to get batteries, &c., into the field.

H. W. HALLECK,

General-in-Chief.

HEADQUARTERS ARMY OF THE POTOMAC,
Near Alexandria, Va., August 31, 1862-7.30 p.m.

(Received 8.20 p.m.)

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

Having been informed that there was some 20,000 stragglers from Pope's army between this and Centreville, all of Gregg's cavalry have been sent to endeavor to drive them back to their regiments. Two hundred of Eighth Illinois Cavalry will be ready in the morning and 250 more as soon as disembarked. The armament of Fort Buffalo is very incomplete.

GEO. B. McCLELLAN,

Major-General.

HEADQUARTERS ARMY OF THE POTOMAC,
Alexandria, August 31, 1862-10.25 p.m.

(Received 10.55 p.m.)

Major General H. W. HALLECK,

General-in-Chief U. S. Army:

I am ready to afford you any assistance in my power; but you will readily perceive how difficult an undefined position, such as I now hold, must be. At what hour in the morning can I see you alone, either at your own house or the office?

GEO. B. McCLELLAN,

Major-General.