CHILE AND ARGENTINA. The broad, high pla teau. with its bordering ranges and subsidiary eastern ranges of Bolivia, extends southward into these countries, gradually narrowing and decreasing in altitude, until in latitude 32° the Andes become reduced to a single range, except for spurs and outliers, most of which are of com paratively little importance. In the northern part the altitude of the ranges decreases great ly, Juneal, in latitude 26°, having a height of 17,530 feet, and Copaip5 volcano, 19,700 feet. Farther south, in the neighborhood of Santiago, the mountains again become loftier. Here are Mercedario, 22,315 feet; Tupungato, 20.286 feet; San Jose, 20,020 feet ; and Aconcagua, 22 860 feet; this latter peak is the highest summit of the entire system, and of the whole continent, so far as known. Still further south, the range again diminishes in height. In latitude 34° is Maipo volcano, 17,670 feet; in latitude 36° is Descabezado, 12,760 feet ; in latitude 42° is Tro nador volcano,. 9790 feet. Here begins the re markable fiord coast, which extends south to Cape Horn. The heavy precipitation on the west side of the range here produced in past times extensive glaciers, which chiseled the mountains far down below sea level, producing many islands, and an intricate system of mountain walled channels. These glaciers have been able, by reason of their rapid descent, to cut back their heads across the range in many places, so that now, after their recession, many of the streams which have succeeded them rise far to the east of the Andes, upon the plains of Argen tina, and flow through the range to the Pacific.
In this region the mountains become still lower, their height ranging from 4000 to 8000 feet, until they finally disappear at Cape Horn.
The lower limit of perpetual snow, although an extremely indefinite line, varying from year to year with exposure and precipitation, has in general, in equatorial regions, an altitude of about 15,500 feet, but ranges a thousand feet on each side of this figure, being higher on the east and lower on the west side of the range. In other words, it is higher where the precipitation is abundant, and lower where it is scanty. It diminishes as the latitude increases, being about 13,000 feet in the latitude of Santiago, and fall ing to 3000 feet near the southern point of the continent, Glaciers are found on all the high peaks, even those in equatorial regions, which exceed 13,000 feet in height. Here, however, they are small, descending the mountain slope only a few thousand feet. In southern Chile, on the west side of the range, are many of consid erable size. originating upon mountains of infe rior height, and descending to sea level, even entering the sea, at the heads of fiords.