I cannot learn the strength of Heintzelman's and Schenck's commands, nor where they are stationed, and hence I send my chief of staff to Washington and Baltimore to ascertain, and also to start out a column of about 15, 000 men on the National road as far as Frederick City. In any contingency, whether of an advance or retreat of the enemy, the defense of Washington or Baltimore, this amount of force should be there, and they should be held in readiness to march, which fact I will not be able to know until I put them on the road. I will send the best officers I have to command this body. I desire that instructions may be given Generals Heintzelman and Schenck to direct their commands to obey promptly any orders they may receive from me.

Last evening the colonel commanding at Poolesville responded to his orders to march that he did not belong to my command, but would refer his orders to General Heintzelman. Such delays may bring us reverses. When these instructions are given, I shall not be necessitated to repeat orders to any part of my command to march on the enemy.

Allow me to suggest that the new troops arriving in Baltimore and Washington be at once put in the defenses, and the old ones, excepting those serving with the artillery, be put in marching condition. If this should be done quickly, I think that we may anticipate glorious results from the recent movement of the enemy, whether he should determine to advance or retreat.

I request that my orders be sent me to-day, for outside of the Army of the Potomac I don't know whether I am standing on my head or feet.

I am, very respectfully, your obedient servant,

JOSEPH HOOKER,

Major-General, Commanding.

WASHINGTON, D. C., June 24, 1863 - 2:30 p. m.

Major-General HOOKER,

Army of the Potomac:

General Schenck has been notified that the troops of his department in Harper's Ferry and vicinity would obey all orders direct from you, and that he would obey your orders in regard to the other troops of his command. They, however, are nearly all militia.

H. W. HALLECK,

General-in-Chief.

HEADQUARTERS ARMY OF THE POTOMAC,
June 25, 1863. (Received 11 a. m.)

Major-General HALLECK:

Subjoined is a dispatch this moment received. It speaks for itself. I request that General Slough be arrested at once and charges will be forwarded as soon as I have time to prepare them. You will find, I fear, when it is too late, that the effort to preserve department lines will be fatal to the cause of the country.

JOSEPH HOOKER,

Major-General.