[Inclosure.]

The rebel Government demands as a condition of any further exchange of prisoners that General Buckner be exchanged. The demand appears to be put forth as a sine qua non. This is presumptuous and insolent. We hold three brigadier-general as prisoners of war-Buckner, taken at Fort Donelson, and Pettigrew and another taken in front of Richmond, whilst Prentiss is the only Federal general held by the rebels. The rebels cannot their three generals in our hands by giving for them three officers of equal rank, and if they undertake to insist that they will have a particular one of he three or stop all exchanges, let them stop the exchanges as soon as they like. We can afford it quite as well as they can. We have five times as many prisoners of all grades as they have.

Considering their condition the rebels try to carry things with quite too high a hand. They have at all times acted upon the assumption that they had a right in negotiating exchanges to give up whom they pleased and to keep whom they pleased. No persuasion has every availed to induce them to exchange Colonel Corcoran. Half a dozen times they have promised and as often they have broken their promises. Their last promise was that they would exchange him if we would let them have the privateers, or semi-pirates, captured by us, but when we sent these to Fortress Monroe to be forwarded to them they violated their engagement as they had so often done before. They presume authoritatively not only what prisoners they won't give up but what ones we shall give up, letting us understand that they will have their own way in both matters, and that if we dislike it or choose to rebel against their dictation all prisoners must remain prisoners. We shall see whether our Government in this day of its power and triumph is to be bullied in that fashion.

Kentucky feels it to be her right to ask that General Buckner shall remain a prisoner during the war. She would feel herself deeply aggrieved by his release. Every loyal man and every loyal woman of our Commonwealth would feel it a personal wrong to themselves. All know that Buckner has been the evil spirit, the field, the devil of our State the corrupter of her youth, the ruthless desolator of her homes. He has been no common traitor; he has been the arch-traitor, and she, with her 30,000 loyal sons in the field ready to pour out their blood to undo as far as possible his accursed work, demands that he shall stay in confinement till the end of the war and then take his trial for treason before the judicial tribunals of the land.

WAR DEPARTMENT, Washington, June 15, 1862.

General JOHN E. WOOL, Baltimore:

It is represented to the Department that Roger W. Hanson and one or more other rebel officers are at large in Baltimore. Please advise the Department immediately whether the statement is true.

By order of the Secretary of War:

C. P. WOLCOTT,

Assistant Secretary of War.

McCLELLAN'S, June 15, 1862.

Honorable EDWIN M. STANTON, Secretary of War:

* * * Colonel Key has had an interesting interview with Howell Cobb to-day, the particulars of which I will explain to you by letter.