The Republic of Mexico, having been relieved from foreign intervention, is earnestly engaged in efforts to reestablish her constitutional system of government. A good understanding continues to exist between our Government and the Republics of Hayti and San Domingo, and our cordial relations with the Central and South American States remain unchanged. The tender, made in conformity with a resolution of Congress, of the good offices of the Government with a view to an amicable adjustment of peace between Brazil and her allies on one side and Paraguay on the other, and between Chile and her allies on the one side and Spain on the other, though kindly received, has in neither case been fully accepted by the belligerents. The war in the valley of the Parana is still vigorously maintained. On the other hand, actual hostilities between the Pacific States and Spain have been more than a year suspended. I shall, on any proper occasion that may occur, renew the conciliatory recommendations which have been already made. Brazil, with enlightened sagacity and comprehensive statesmanship, has opened the great channels of the Amazon and its tributaries to universal commerce. One thing more seems needful to assure a rapid and cheering progress in South America. I refer to those peaceful habits without which states and nations can not in this age well expect material prosperity or social advancement. The Exposition of Universal Industry at Paris has passed, and seems to have fully realized the high expectations of the French Government. If due allowance be made for the recent political derangement of industry here, the part which the United States has borne in this exhibition of invention and art may be regarded with very high satisfaction. During the exposition a conference was held of delegates from several nations, the United States being one, in which the inconveniences of commerce and social intercourse resulting from the diverse standards of money value were very fully discussed, and plans were developed for establishing by universal consent a common principle for the coinage of gold. These conferences are expected to be renewed, with the attendance of many foreign states not hitherto represented. A report of these interesting proceedings will be submitted to Congress, which will, no doubt, justly appreciate the great object and be ready to adopt any measure which may tend to facilitate its ultimate accomplishment. On the 25th of February, 1862, Congress declared by law that Treasury notes, without interest, authorized by that act should be legal tender in payment of all debts, public and private, within the United States. An annual remittance of $30,000, less stipulated expenses, accrues to claimants under the convention made with Spain in 1834. These remittances, since the passage of that act, have been paid in such notes. The claimants insist that the Government ought to require payment in coin. The subject may be deemed worthy of your attention.