The unsettled state of our relations with Mexico has involved this subject in much mystery. The first information in an authentic form from the agent of the United States, appointed under the Administration of my predecessor, was received at the State Department on the 9th of November last. This is contained in a letter, dated the 17th of October, addressed by him to one of our citizens then in Mexico with a view of having it communicated to that Department. From this it appears that the agent on the 20th of September, 1844, gave a receipt to the treasury of Mexico for the amount of the April and July installments of the indemnity. In the same communication, however, he asserts that he had not received a single dollar in cash, but that he holds such securities as warranted him at the time in giving the receipt, and entertains no doubt but that he will eventually obtain the money. As these installments appear never to have been actually paid by the Government of Mexico to the agent, and as that Government has not, therefore, been released so as to discharge the claim, I do not feel myself warranted in directing payment to be made to the claimants out of the Treasury without further legislation. Their case is undoubtedly one of much hardship, and it remains for Congress to decide whether any, and what, relief ought to be granted to them. Our minister to Mexico has been instructed to ascertain the facts of the case from the Mexican Government in an authentic and official form and report the result with as little delay as possible. My attention was early directed to the negotiation which on the 4th of March last I found pending at Washington between the United States and Great Britain on the subject of the Oregon Territory. Three several attempts had been previously made to settle the questions in dispute between the two countries by negotiation upon the principle of compromise, but each had proved unsuccessful. These negotiations took place at London in the years 1818, 1824, and 1826--the two first under the Administration of Mr. Monroe and the last under that of Mr. Adams. The negotiation of 1818, having failed to accomplish its object, resulted in the convention of the 20th of October of that year. By the third article of that convention it was--