Coahuila, with an area of 65,000 square miles, and a population of 300,000 inhabitants, is also bounded on the north by the Rio Grande and Texas. The state consists principally of flat plains intersected by small mountain ranges. The rainfall is generally scarce, although abundant at certain seasons in the more mountainous regions, whilst the climate is very variable, being hot and unhealthy in places, although in general terms it cannot be pronounced bad. The great plateau of Mexico, of which it forms part, comes down to a low elevation towards the Rio Grande, whilst the principal mountain ranges are offshoots of the Eastern Sierra Madre. Agriculture is carried on mainly under irrigation from canals fed from the torrential streams which occur sparsely in the state, and great quantities of cotton are grown. The cotton belt and industry are most important, and the wines of Parras are famous in the country. Coahuila, in common with others of its neighbouring states, possesses some peculiar topographical conditions--portions of it consisting of plains or valleys with no hydrographic outlet, as shown in the chapter dealing with the orography of the Republic. These in some cases form fertile valleys, and, in others, sun-beat deserts, uncultivated and uninhabited. Notwithstanding its partly sterile nature this state is a very prosperous commercial section of the country, due largely to its excellent railway system, five different lines of which traverse it. These are the Mexican Central, the International, the Northern, the National, and other lesser systems. In addition there are some fair roads, upon which the traveller may journey by _diligencia_ or on horseback. The capital, Saltillo, with a population of about 25,000, is a pretty and interesting old Spanish town, and a valuable commercial centre. Manufacturing industries have increased rapidly of late years in this state, especially those producing textile fabrics from the native cotton. Metal and coal mining are both developing in this region; and new towns, of which Torreon is an example, are springing up. The state contains one of the principal points of entry to the Republic from the United States--Eagle Pass, or Ciudad Porfirio Diaz, on the International Railway, whilst Laredo, on the National, is near its border.