these army corps will at once establish their headquarters with their troops. the Headquarters of the Army of the Potomac being in the field, no general officer will leave his command without permission from these headquarters. The perfection of the new organization renders it necessary to conform to this order without delay.

GEO. B. McCLELLAN,

Major-General, Commanding.

HEADQUARTERS ARMY OF THE POTOMAC,
Seminary, March 17, 1862-11.50 p. m.

Brigadier General E. V SUMNER:

Until further orders suspend execution of telegraphic order sent herewith in regard to concentration of army corps near Alexandria. your two divisions now with you will remain under previous orders for the present, but will promptly be relieved. Sedgvick's division will proceed to this vicinity under orders from these headquarters. Communicate fully and frequently.

GEO. B. McCLELLAN,

Major-General, Commanding.

(Copy to Secretary of War.)

WASHINGTON, D. C., March 17, 1862.

Major General JOHN E. WOOL,

Commanding Department, Fort Monroe, Va.:

GENERAL: I am instructed by General McClellan, commanding the Department of the Potomac, to inform you that General Hamilton's division of the Army of the Potomac will sail for Fort Monroe, where it will await further orders from General McClellan.

General Hamilton has been directed, in the event of your requiring the services of his division for repelling as attack, to obey all orders coming from you and to use his utmost efforts to carry out your views.

General McClellan telegraphed to you yesterday informing you that General Hamilton's division would sail to-day.

I am, very respectfully, your obedient servant,

R. B. MARCY,

Chief of Staff.

HEADQUARTERS DEPARTMENT OF VIRGINIA,
Fort Monroe, Va., March 17, 1862

Major-General MCCLELLAN,

Washington, D. C.:

To the instructions of the Secretary of War of the 16th, by telegram, just received, 10 o'clock a. m., I reply that I have already communicated to him and yourself "all the information I have regarding the strength and disposition of the enemy's forces between Yorktown and James River". I repeat, about ten days ago I received what was considered reliable information that Magruder had between Gloucester (opposite to Yorktown) and James River from 15,000 to 18,000 men, and at Norfolk and the surrounding country about 18,000.