to cross. General Pleasonton, with a large cavalry force, is moving out intercept them, and if they come in your direction he will probably be near them. We shall have two brigades of infantry at Frederick to-night. Communicate any information of the enemy's movements to these headquarters from time to time.

The following has just been received from General Pleasonton:

NEAR MOUTH OF THE MONOCACY, MD.

R. B. MARCY, Chief of Staff:

General Stoneman has asked me for some cavalry to send over the river after the rebels. I have told him that the infantry and cavalry are wholly unfit for service, and could not follow the enemy until recuperated. My whole command of cavalry and artillery to-day was not more than 800 men. My force of cavalry was two regiments and a half-both regiments small. Of the other regiments ordered to report to me, I have not heard. A force of infantry and cavalry from Poolesville arrived after the enemy had crossed the river. Unless otherwise ordered, I shall move back to my camp near

Sharpsburg, to-morrow. My horses need rest and shoeing very badly.

It appears that a regiment of infantry stationed near the ford where the crossed did not engage attempt to stop them from crossing. I do not know the name of this regiment.

A. PLEASONTON,

Brigadier-General, Commanding.

General Stoneman has been directed to furnish an immediate report as to the manner in which he carried out the instructions contained in the dispatch of the 11th.

R. B. MARCY,

Chief of Staff.

OCTOBER 13, 1862-9 a. m.

General A. PLEASONTON,

Near mouth of the Monocacy, via Poolesville:

Your dispatch of this morning received.* You will march your command to-morrow morning to these headquarters, which you will find near Burnside's headquarters, in Pleasant Valley, and report for further orders.

No troops will be allowed to cross the river near you position to-day.

R. B. MARCY

Chief of Staff.

OCTOBER 13, 1862-9 A. M.

General GEORGE STONEMAN, Poolesville, Md.:

The commanding general directs that you will not send a detachment across the Potomac, as he conceives it to late now to attempt to follow Stuart with you command.

R. B. MARCY

Chief of Staff.

HEADQUARTERS DEFENSES OF WASHINGTON,
October 13, 1862-1 p. m.

Brigadier General GEORGE STONEMAN, Poolesville:

The commanding general thinks you had better report to General McClellan to-day. General Grover will proceed to join to-morrow.

Leave him a battery and some cavalry. We will relieve the battery as soon as possible and return it to you.

RICH'D B. IRWIN,

Captain, Aide-de-Camp, and Acting Assistant Adjutant-General.

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* See Marcy to Halleck, 9 a. m., p. 76

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