The rejection by the Mexican Congress of the convention which had been concluded between that Republic and the United States for the protection of a transit way across the Isthmus of Tehuantepec and of the interests of those citizens of the United States who had become proprietors of the rights which Mexico had conferred on one of her own citizens in regard to that transit has thrown a serious obstacle in the way of the attainment of a very desirable national object.  I am still willing to hope that the differences on the subject which exist, or may hereafter arise, between the Governments will be amicably adjusted.  This subject, however, has already engaged the attention of the Senate of the United States, and requires no further comment in this communication.

The settlement of the question respecting the port of San Juan de Nicaragua and of the controversy between the Republics of Costa Rica and Nicaragua in regard to their boundaries was considered indispensable to the commencement of the ship canal between the two oceans, which was the subject of the convention between the United States and Great Britain of the 19th of April, 1850.  Accordingly, a proposition for the same purposes, addressed to the two Governments in that quarter and to the Mosquito Indians, was agreed to in April last by the Secretary of State and the minister of Her Britannic Majesty.  Besides the wish to aid in reconciling the differences of the two Republics, I engaged in the negotiation from a desire to place the great work of a ship canal between the two oceans under one jurisdiction and to establish the important port of San Juan de Nicaragua under the government of a civilized power.  The proposition in question was assented to by Costs Rica and the Mosquito Indians.  It has not proved equally acceptable to Nicaragua, but it is to be hoped that the further negotiations on the subject which are in train will be carried on in that spirit of conciliation and compromise which ought always to prevail on such occasions, and that they will lead to a satisfactory result.

I have the satisfaction to inform you that the executive government of Venezuela has acknowledged some claims of citizens of the United States which have for many years past been urged by our charge d’affaires at Caracas.  It is hoped that the same sense of justice will actuate the Congress of that Republic in providing the means for their payment.

The recent revolution in Buenos Ayres and the Confederated States having opened the prospect of an improved state of things in that quarter, the Governments of Great Britain and France determined to negotiate with the chief of the new confederacy for the free access of their commerce to the extensive countries watered by the tributaries of the La Plata; and they gave a friendly notice of this purpose to the United States, that we might, if we thought proper, pursue the same course.  In compliance with this invitation, our minister at Rio Janeiro and our charge d’affaires at Buenos Ayres have been fully authorized to conclude treaties with the newly organized confederation or the States composing it.  The delays which have taken place in the formation of the new government have as yet prevented the execution of those instructions, but there is every reason to hope that these vast countries will be eventually opened to our commerce.