be neceſsary.
The Boundary line established by this Article shall be religiously respected by each of the two Republics, and no change shall ever be made therein, except by the expreſs and free consent of both nations, lawfully given by the General Government of each, in conformity with it’s 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 below it’s confluence with the Gila, to and from their poſseſsions situated north of the Boundary line defined in the preceding Article: it being understood, that this paſsage is to be by navigating the Gulf of California and the River Colorado, and not by land, without the expreſs consent of the Mexican Government.
If, by the examinations which 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 it’s right or it’s left bank, within the space of one marine league from either margin
