The towns of New Biscay of the greatest note after Durango, are _Chihuahua_, formerly the residence of the captain-general of all the interior provinces of the upper part of the viceroyalty of New Spain, and now the residence of the captain-general of the western interior provinces, which comprehend New Biscay, New Mexico, Sonora, and the two Californias. The population of Chihuahua is 11,600, and it is surrounded with mining stations, the principal of which is _Santa Rosa de Cosiquiriachi_, where that part of the Sierra Madre, called De los Metales, has valuable and numerous silver mines; this mining station is peopled by 10,700 souls. _Mapimis_, on the south extremity of the desert of Mapimi, is a military port, with 2700 inhabitants. _St. Juan del Rio_, south of Lake Parras, 10,200 souls. _Saltillo_, situated to the west of Monterey, in New Leon, on a barren dry soil; 6000 people. _Pasquaro_, south of Rio de Nasas; 5600. _Batopilas_, west of Rio Conchos, 8000, formerly a place of great repute for its mines. _Parral_ the seat of a council of mines, 5000, and the mining station of _Guirisamey_, 3800. The population of this government is concentrated entirely in these towns and in the mining stations, as in New Mexico, the warlike Indians rendering this method of living necessary; even the forts are well peopled, as the settlers choose to live under their protection, in preference to possessing large tracts of land at a distance from any defence. _INTENDANCY OF SAN LUIS POTOSI._ THE intendancy of San Luis Potosi, comprises the provinces of Coaguila, New Leon, Texas, and the colonies of New Santander; and forms the western captain-generalship of the interior provinces. It is bounded on the north by desart countries, inhabited by tribes of wandering Indians; by the Bolson de Mapimi, an unconquered desart on the west, as well as by part of New Biscay and Zacatecas; on the south by the intendancies of Guanaxuato, Mexico, and Vera Cruz. On the east its limits are not defined; by the Spaniards they are considered to reach to the river Mexicano or Mermento, between the sixty-fifth and sixty-sixth degrees of west longitude, but the American congress deny this being the boundary of Louisiana, and extend their claims as far as the bay of St. Bernardo. This intendancy is computed to have a population of 334,900 souls. That part of San Luis Potosi which joins Zacatecas, is a mountainous country; in New Leon the land is not high, consequently the summers are hot and the winters cold; the land on the right, between Coaguila and Louisiana, is represented as containing impervious savannahs and enormous desarts. The nearest post of the Americans to New Spain, is Fort Clayborne, on the Red River. In the greater part of this immense territory of San Luis the climate is good, and the air pure and healthy.