est to such branch, and thence in a direct line to the same) thence down the middle of the said branch and of the said river, until it empties into the Rio Colorado; thence across the Rio Colorado, following the division line between Upper and Lower California, to the Pacific Ocean.
The southern and western limits of New Mexico, mentioned in this article, are those laid down in the map entitled "Map of the United Mexican States, as organized and defined by various acts of the Congress of said Republic and constructed according to the best authorities. Revised edition. Published at New York in 1847, by J. Disturnell."
Of which map a copy is added to this Treaty, bearing the signatures and seals of the undersigned Plenipotentiaries. And in order to preclude all difficulty in tracing upon the ground the limit separating Upper from Lower California, it is agreed that the said limits shall consist of a straight line, drawn from the middle of the Rio Gila, where it unites with the Colorado, to a point on the coast of the Pacific Ocean—distant one marine league due south of the southernmost point of the port of San Diego according to the plan of said port, made in the year 1782, by Don Juan Pantojer, second sailing master of the Spanish fleet, and published at Madrid in the year 1802, in the Atlas to the voyage of the schooner Sutil and Mexicana, of which plan a copy is hereunto added, signed and sealed by the respective Plenipotentiaries.
In order to designate the boundary line with due precision, upon authoritative maps, and to establish on the ground landmarks which shall show the limits of both Republics, as described in the present article, the Governments shall each appoint a Commissioner and Surveyor, who, before the expiration of one year from the date of the exchange of ratification of this Treaty, shall meet at the Port of San Diego, and proceed to run and mark the said boundary in its whole course to the mouth of the Rio Bravo del Norte. They shall keep journals and make out plans of their operations; and the result agreed upon by them shall be deemed a part of this Treaty, and shall have the same force as if it were inserted therein. The two Governments will amicably agree regarding what may be necessary to these persons, and also as to their respective escorts, should such be necessary.
The boundary line established by this article shall be religiously respected by each of the two Republics, and no change shall be made therein, except by the express and free consent of both Nations, lawfully given by the General Geverament of each, in conformity with its own Constitution.
ARTICLE VI.
The vessels and citizens of the United States shall, in all time, have a free and uninterrupted passage by the Gulf of California, and by the river Colorado; and not by land without the express consent of the Mexican Government.
If, by the examinations that may be made, it should be ascertained to be practicable and advantageous to construct a Road, Canal, or Railway, which should, in whole or in part, run upon the river Gila, or upon its right or its left bank, within the space of one marine league from either margin of the river, the Governments of both Republics will form an agreement regarding its construction, in order that it may serve equally for the use and advantage of both countries.
ARTICLE VII.
The river Gila, and the part of the Rio del Norte lying below the southern boundary of New Mexico, being agreeably to the Fifth Article, divided in the middle between the two republics, the navigation of the Gila and of the Bravo, below said boundary shall be free and common to the vessels and citizens of both countries; and neither shall, without the consent of the other construct any work that may impede or interrupt in whole or in part, the exercise of this right—not even for the purpose of favoring new methods of navigation. Nor shall any tax or contribution, under any denomination or title be levied upon vessels or persons navigating the same, or upon merchandise, or effects transported thereon, except in the case of landing upon one of their shores. If, for the purpose of making said rivers navigable, or for maintaining them in such a state, it should be necessary or advantageous to establish any tax or contribution, this shall not be done without the consent of both Governments.
The stipulations contained in the present article shall not impair the territorial rights of either republic, within its established limits.
ARTICLE VIII.
Mexicans now established in territories previously belonging to Mexico, and which remain for the future, within the limits of the United States, as defined by the present Treaty, shall be free to continue where they now reside, or to remove, at any time, to the Mexican Repub-
