DEPARTMENT OF STATE, Washington, August 12, 1861.

Mr. A. W. THAYER, Northampton, Mass.

MY DEAR SIR: Your favor of the 10th instant has been received, together with the newspaper mentioned therein containing what purports to be a letter from a surgeon of the U. S. Army stationed at Arlington Heights containing strictures upon the Army, members of the administration and others, and in which it is stated that "Seward is drunk from morning till night. " You tell me that if it is thought best you think you could find out who is the writer of the communication. I give you my sincere thanks for the kindness which prompted you to bring this matter to my notice, but I have not the least interest in discovering the author of the communication. It has been a habit of my life to leave my conduct and character to the vindication of time and truth.

I am, my dear sir, very truly, yours,

WILLIAM H. SEWARD.

HEADQUARTERS DIVISION OF THE POTOMAC,
Washington, August 12, 1861.

Brigadier-General MANSFIELD,

Commanding Department of Washington.

GENERAL: You will please take no action in regard to the detective police of Washington as to secessionists. The subject is fully covered by proceedings from these headquarters in connection with the action of the provost-marshal.

I am, very respectfully, your obedient servant,

GEO. B. McCLELLAN,

Major-General, Commanding.

HEADQUARTERS OF THE ARMY,
Washington, August 13, 1861.

Honorable SECRETARY OF WAR.

SIR: Lieutenant Colonel Martin Burke, U. S. Army, has been assigned to the command of Forts Hamilton and Lafayette for the purpose of supervising the safe custody of the political prisoners and prisoners of war confined in the latter fort. In accordance with the wishes of the honorable Secretary of State instructions of which the inclosed are copies have already been given in relation to the said prisoners. I beg leave to suggest that the letters written by the prisoners to their friends having a political rather than a military bearing should be sent to the Department of State for examination to ascertain whether they may be properly forwarded to their address, or if not what should be done with them. Applications for permission to visit the prisoners should be submitted it is supposed to the same Department.

I have the honor to be, sir, very respectfully, your obedient servant,

WINFIELD SCOTT.

[Inclosure.]

HEADQUARTERS OF THE ARMY,
Washington, August 2, 1861.

Lieutenant Colonel MARTIN BURKE, U. S. Army,

Commanding, &c., Numbers 6 State Street, New York City:

Should the writ of habeas corpus come for the production in court of any of your political prisoners you will respond thereto that you deeply