In my letter of the 18th, I had the honor to mention some things, which lay upon my mind; but still I am apprehensive, that in a former letter, I have not conveyed my full meaning to your Excellency. In my letter of the 16th, I submitted to your Excellency's opinion and advice, whether an American Minister could appear at the Congress at Vienna, without having his character acknowledged by any power, more expressly than it is now. This was said upon the supposition, and taking it for granted, that it was the intention of the mediating Courts to admit a representative of the United States to the Congress, with such a commission and such a title as the United States should think fit to give him, and that during his whole residence and negotiations at Vienna, whether they should terminate in peace or not, he should enjoy all the prerogatives, which the law of nations has annexed to the character, person, habitation, and attendants of such a Minister. It is impossible that there should be a treaty at Vienna between Great Britain and the people of America, whether they are called United States or American Colonies, unless both nations appear there by representatives, who must be authorised by commissions or full powers, which must be mutually exchanged, and consequently admitted to be, what upon the face of them they purport to be. The commission from the United States for making peace, which has been in Europe almost two years, is that of a Minister Plenipotentiary, and it authorises him to treat only with Ministers vested with equal powers. If he were to appear at Vienna, he would certainly assume the title and character of a Minister Plenipotentiary, and could enter into no treaty or conference with any Minister from Great Britain, until they had mutually exchanged authentic copies of their full powers. This it is true, would be an implied acknowledgment of his character and title, and of those of the United States too; but such an acknowledgment is indispensable, because without it there can be no treaty at all. In consequence he would expect to enjoy all the prerogatives of that character, and the moment they should be denied him, he must quit the Congress, let the consequences be what they might.