If this be so, and you are so willing to exchange these colored men claimed as slaves, and you will so officially inform the government of the United States, then, as I am instructed, a principal difficulty in effecting exchanges will be removed.

As I informed you personally, in my judgment it is neither consistent with the policy, dignity, or honor of the United States, upon any consideration, to allow those who, by our laws solemnly enacted, are made soldiers of the Union, and who have been duly enlisted, enrolled, and mustered as such soldiers, who have borne arms in behalf of this country, and who have been captured while fighting in vindication of the rights of that country, not to be treated as prisoners of war, and remain unchanged and in the service of those who claim them as masters; and I cannot believe that the government of the United States will ever be found to consent to so gross a wrong.

Pardon me if I misunderstand you in supposing that your acceptance of our proposition does not in good faith mean to include all the soldiers of the Union, and that you still intend, if your acceptance is agreed to, to hold the colored soldiers of the Union unexchanged, and at labor or service, because I am informed that very lately, almost contemporaneously with this offer on your part to exchange prisoners, and which seems to include all prisoners of war, the Confederate authorities have made a declaration that the negroes heretofore held to service by owners in the States of Delaware, Maryland, and Missouri are to be treated as prisoners of war, when captured in arms in the service of the United States.

Such declaration that a part of the colored soldiers of the United States were to be prisoners of war, would seem most strongly to imply that others were not to be so treated, or, in other words, that the colored men from the insurrectionary States are to be held to labor and returned to their masters, if captured by the Confederate forces while duly enrolled and mustered into and actually in the armies of the United States.

In the view which the government of the United States takes of the claim made by you to the persons and services of these negroes, it is not to be supported upon any principle of national and municipal law.

Looking upon these men only as property upon your theory of property in them, we do not see how this claim can be made, certainly not how it can be yielded. It is believed to be a well-settled rule of public international law, and a custom and part of the laws of war, that the capture of movable property vests the title to that property in the captor, and therefore where one belligerent gets into full possession property belonging to the subjects or citizens of the other belligerent, the owner of that property is at once divested of his title, which rests in the belligerent government capturing and holding such possessions. Upon this rule of international law all civilized nations have acted, and by it both belligerents have dealt with all property, save slaves, taken from each other during the present war.

If the Confederate forces capture a number of horses from the United States, the animals are claimed to be, and, as we understand it, become the property of the Confederate authorities.

If the United States capture any movable property in the rebellion, by our regulations and laws, in conformity with international law and the laws of war, such property is turned over to our government as its property. Therefore, if we obtain possession of that species of property known to the laws of the insurrectionary States as slaves, why should there be any doubt that that property, like any other, vests in the United States?

If the property in the slave does so vest, then the jus disponendi, the right of disposing of that property, vests in the United States.

Now, the United States have disposed of the property which they have acquired by capture in slaves taken by them, i.e., by emancipating them, and declaring them free forever; so that, if we have not mistaken the principles of international law and the laws of war, we have no slaves in the armies of the United States. All are free men, being made so in such manner as we have chosen to dispose of our property in them which we acquired by capture.