2d. The Rio del Tigre, rises in the state of Coahuila, and passes, in a southward and easterly direction, through the states of New Leon and Tamaulipas, and finally, after traversing about three hundred miles, debouches in the Gulf of Mexico.
3d. The Rio de Borbon, or Rio Blanco. The sources of this stream are in New Leon, whence it runs towards the east, and, crossing the state of Tamaulipas, falls in the Laguna Madre.
4th. The Rio de Santander, rises in the state of Zacatecas, crosses the state of San Luis Potosi, passes by Tamaulipas, winds to the north, and falls, near the bar of Santander, into the Gulf.
5th. The Rio de Tampico, is formed by the union of the rivers Panuco and Tula. The upper source of the Panuco is in the neighborhood of the city of San Luis Potosi, the capital of the state of that name. Near half a league north north-east of this city, in the valley de la Pila, rises a spring which is protected by a basin of fine masonry, and conveyed by an aqueduct to