I herewith transmit a communication from the Secretary of the Navy, accompanied by the second part of Lieutenant Herndon's report of the exploration of the valley of the Amazon and its tributaries, made by him in connection with Lieutenant Lardner Gibbon under instructions from the Navy Department. FRANKLIN PIERCE. WASHINGTON, _February 10th, 1854_. _To the Senate of the United States_: I transmit to the Senate, for its consideration with a view to ratification, a treaty between the United States and the Mexican Republic, signed by the plenipotentiaries of the parties in the City of Mexico on the 30th of December last. Certain amendments are proposed to the instrument, as hereinafter specified, viz: In order to make the duties and obligations stipulated in the second article reciprocal, it is proposed to add to that article the following: And the Government of Mexico agrees that the stipulations contained in this article to be performed by the United States shall be reciprocal, and Mexico shall be under like obligations to the United States and the citizens thereof as those hereinabove imposed on the latter in favor of the Republic of Mexico and Mexican citizens. It is also recommended that for the third article of the original treaty the following shall be adopted as a substitute: In consideration of the grants received by the United States and the obligations relinquished by the Mexican Republic pursuant to this treaty, the former agree to pay to the latter the sum of $15,000,000 in gold or silver coin at the Treasury at Washington, one-fifth of the amount on the exchange of ratifications of the present treaty at Washington and the remaining four-fifths in monthly installments of three millions each, with interest at the rate of 6 per cent per annum until the whole be paid, the Government of the United States reserving the right to pay up the whole sum of fifteen millions at an earlier date, as may be to it convenient. The United States also agree to assume all the claims of their citizens against the Mexican Republic which may have arisen under treaty or the law of nations since the date of the signature of the treaty of Guadalupe, and the Mexican Republic agrees to exonerate the United States of America from all claims of Mexico or Mexican citizens which may have arisen under treaty or the law of nations since the date of the treaty of Guadalupe, so that each Government, in the most formal and effective manner, shall be exempted and exonerated of all such obligations to each other respectively. I also recommend that the eighth article be modified by striking out all after the word "attempts" in the twenty-third line of that article. The part to be omitted is as follows: