_Physiography._--For purposes of general topographical description Chile may be divided into three regions: the desert region of the north, the central agricultural region between the provinces of Coquimbo and Llanquihue, and the heavily-forested rainy region south of lat. 41° S. The desert region is an elevated arid plateau descending gradually from the Andes towards the coast, where it breaks down abruptly from elevations of 800 to 1500 ft. From the sea this plateau escarpment has the appearance of a range of flat topped hills closely following the coast line. The surface is made up of extensive plains covered with sand and deposits of alkaline salts, broken by ranges of barren hills having the appearance of spurs from the Andes, and by irregular lateral ranges in the vicinity of the main cordillera enclosing elevated saline plateaus. This region is rainless, barren and inhospitable, absolutely destitute of vegetation except in some small river valleys where irrigation is possible, and on the slopes of some of the snow-covered peaks where the water from the melting snows nourishes a scanty and coarse vegetation before it disappears in the thirsty sands. It is very rich in mineral and saline deposits, however. The eastern parts of this region lie within the higher ranges of the Andes and include a large district awarded to Chile in 1899 (see ARGENTINA and ATACAMA). This arid, bleak area is apparently a continuation southward of the great Bolivian _altaplanicie_, and is known as the Puna de Atacama. Its average elevation is estimated at 11,000 to 12,000 ft. A line of volcanoes crosses it from north to south, and extensive lava beds cover a considerable part of its surface. Large shallow saline lakes are also characteristic features of this region. From 28° S. the spurs from the cordillera toward the coast are more sharply defined and enclose deeper valleys, where the cultivation of the soil becomes possible, at first through irrigation and then with the aid of light periodical rains. The slopes of the Andes are precipitous, the general surface is rough, and in the north the higher ground and coast are still barren. Beginning with the province of Aconcagua the coast elevations crystallize into a range of mountains, the Cordillera Maritima, which follows the shore line south to the province of Llanquihue, and is continued still farther south by the mountain range of Chiloé and the islands of the western coast, which are the peaks of a submerged mountain chain. Lying between this coast range and the Andes is a broad valley, or plain, extending from the Aconcagua river south to the Gulf of Ancud, a distance slightly over 620 m. with an average width of about 60 m. It is sometimes called the "Vale of Chile," and is the richest and most thickly-populated part of the republic. It is a highly fertile region, is well watered by numerous streams from the Andes, has a moderate rainfall, and forms an agricultural and grazing region of great productiveness. It slopes toward the south, and its lower levels are filled with lakes and with depressions where lakes formerly existed. It is an alluvial plain for the greater part, but contains some sandy tracts, as in Ñuble and Arauco; in the north very little natural forest is found except in the valleys and on the slopes of the enclosing mountain ranges, but in the south, where the rainfall is heavier, the plain is well covered with forest. South of 41° S. the country is mountainous, heavily-forested and inhospitable. There are only a few scattered settlements within its borders, and a few nomadic tribes of savages eke out a miserable existence on the coast. The deeply-indented coast line is filled with islands which preserve the general outline of the continent southward to the Fuegian archipelago, the outside groups forming a continuation of the Cordillera Maritima. The heavy and continuous rainfall throughout this region, especially in the latitude of Chiloé, gives rise to a large number of rivers and lakes. Farther south this excessive precipitation is in the form of snow in the Cordilleras, forming glaciers at a comparatively low level which in places discharge into the inlets and bays of the sea. The extreme southern part of this region extends eastward to the Atlantic entrance to the Straits of Magellan, and includes the greater part of the large island of Tierra del Fuego with all the islands lying south and west of it. There are some comparatively level stretches of country immediately north of the Straits, partly forested and partly grassy plains, where sheep farming has been established with some degree of success, but the greater part of this extreme southern territory is mountainous, cold, wet and inhospitable.