We inclose a copy of our address to the President, and also a copy of his reply.  Several conferences afterwards took place between Messrs. Rosa, Cuevas, Conto, and ourselves, which it is not thought necessary to recapitulate, as we inclose a copy of the protocol, which contains the substance of the conversations.  We have now the satisfaction to announce that the exchange of ratifications was effected to-day.

This dispatch was communicated with my message of the 6th of July last, and published by order of Congress.

The treaty, as amended by the Senate of the United States, with the accompanying papers and the evidence that in that form it had been ratified by Mexico, was received at Washington on the 4th day of July, 1848, and immediately proclaimed as the supreme law of the land.  On the 6th of July I communicated to Congress the ratified treaty, with such accompanying documents as were deemed material to a full understanding of the subject, to the end that Congress might adopt the legislation necessary and proper to carry the treaty into effect.  Neither the address of the commissioners, nor the reply of the President of Mexico on the occasion of their presentation, nor the memorandum of conversations embraced in the paper called a protocol, nor the correspondence now sent, were communicated, because they were not regarded as in any way material; and in this I conformed to the practice of our Government.  It rarely, if ever, happens that all the correspondence, and especially the instructions to our ministers, is communicated.  Copies of these papers are now transmitted, as being within the resolutions of the House calling for all such “correspondence as appertains to said treaty.”

When these papers were received at Washington, peace had been restored, the first installment of three millions paid to Mexico, the blockades were raised, the City of Mexico evacuated, and our troops on their return home.  The war was at an end, and the treaty, as ratified by the United States, was binding on both parties, and already executed in a great degree.  In this condition of things it was not competent for the President alone, or for the President and Senate, or for the President, Senate, and House of Representatives combined, to abrogate the treaty, to annul the peace and restore a state of war, except by a solemn declaration of war.

Had the protocol varied the treaty as amended by the Senate of the United States, it would have had no binding effect.

It was obvious that the commissioners of the United States did not regard the protocol as in any degree a part of the treaty, nor as modifying or altering the treaty as amended by the Senate.  They communicated it as the substance of conversations held after the Mexican Congress had ratified the treaty, and they knew that the approval of the Mexican Congress was as essential to the validity of a treaty in all its parts as the advice and consent of the Senate of the