WAR DEPARTMENT, Washington, May 15, 1861.

His Excellency WILLIAM SPRAGUE,

Governor of Rhode Island:

DEAR SIR: I have the honor to acknowledge the receipt of your letter of the 13th instant, and respectfully beg leave to inform you in reply that it has received the consideration due to its distinguished source.

It is not doubted that if you were serving officially with the Rhode Island troops now here in service your influence with and over them would be such as to induce them to re-enlist at the expiration of their present service for another period of three months, and so continue until the expiration of the war, and it would afford this Department great pleasure to adopt this suggestion, if practicable in other respects, and thus secure to the Government the benefit of the valuable services you could render it in the manner suggested. But I regret to say this mode of retaining troops in service appears to me, after mature consideration, to be attended with such serious objections in other respects that I would not be justified to adopt it. Others now in service would regard it as a precedent for themselves, and claim it to be applied to themselves, and the result to be feared flowing from it might be the demoralization of the troops mustered into service for the war. Fearful of this, and unwilling to make a larger draft upon the patriotism of your gallant State than is absolutely necessary, the Government prefers to content itself with the service of one regiment from Rhode Island for three years, or during the war, rather than adopt a mode of retaining that now in service which might possibly prove injurious in its influence upon the troops now in service for the war.

In regard to the other suggestion of your letter, I can only say now that, with all my own inclinations in favor of it, I am yet met with obstacles in the way of its consummation which are embarrassing and difficult for me to overcome at this time. The President and his official advisers have deemed the interest of the public service to demand the promotion of General Benjamin F. Butler, and he has accordingly been appointed a major-general. This gives the New England States one officer in the Army of the new appointments of the highest rank, and as there will be at present necessarily only a few of this grade, the President will be obliged in making the selections [to choose from] another part of the Union. Still anxious, however, to secure to the Government your services during the war, may you not yet be able so to arrange matters as to enable you to serve as a brigadier-general?

With assurances of my high regard, I am, sir, very respectfully,

SIMON CAMERON,

Secretary of War.

WAR DEPARTMENT, Washington, May 15, 1861.

Governor ALEXANDER W. RANDALL,

Madison, Wis.:

DEAR SIR: I have the honor to acknowledge the receipt of your letter of the 6th instant, addressed to the President of the United States, and by him referred to this Department, giving an account of the proceedings of a meeting of the Governors of a number of the States, held at Cleveland, on the 6th [3rd] instant, and containing suggestions in regard to the condition of public affairs.