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MOUNTAINS ; the largest elevations of the surface of the earth. Hills are distinguished from mountains by inferior height. Several mountains together, which cover a plain, are called a group of mountains ; mountains that form a series of several miles in length, a chain or ridge of mountains. Single mountains, rising out of a plain country, are seldom met with. The cavities between the mountains are termed valleys. The seacoasts are generally the lowest part of a country, which gradually rises, so that the centre of a continent is the highest, and is covered with considerable mountains. The chief mountains are connected in extensive chains all over the surface of the globe. The Ural mountains, which separate Asia from Europe, and send forth a branch towards Nova Zembla, are connected with the Severnoi or Sevous ridge, that forms the boundary between Norway and Sweden, and a part of Russia. Another chain stretches from the northern part of India to Thibet and Cashmere, where it forms the highest region, not only of Central Asia, but of the known world, running westward through Persia, and eastward through China. From the highest elevation of Northern Asia, the Bogdo mountains, which separate the seats of the Calmucks from those of the Mongols, a chain of mountains under the name of Mossart runs southward to Thibet: another, under the name of Mak, extends towards the west through the deserts of Independent Tartary and Bucharia, and joins the Ural mountains: a third, under the name of Zangai, in Mongolia, stretches eastward, then, turning, forms Corea and the cliffs and islands toward Japan: a fourth chain consists of the Altai mountains, which border on Siberia, from the Irtish to the Amour. The branches of these great Asiatic chains are innumerable. Between the Caspian and Black seas, the Caucasus (q. v.) is situated. It sends off branches through Asia Minor as far as Arabia, which form the ridges of Taurus, Lebanon and Sinai, while others pass round the Black sea to Europe. From the Black sea, between Moldavia, Walachia and Transylvania, the Carpathians extend through Poland and Hungary, and, in Silesia, join the mountainous regions of Germany. The Sudetes run between Bohemia and Silesia, sending forth branches to the north and west, through Lusatia to the Saxon Erzgebirge, and Voigtland. The Fiehtelgebirge and the Thuringerwald, or Forest of Thuringia, together with the Eichsfeld and the northern Hartzgebirge, extend through the centre of Germany. The most elevated countries of Europe are Switzerland and Savoy, whose Alps (q.v.) are connected with the neighboring chains of Germany, Italy and France. A branch, united with them, the Apennines, running through all Italy as far as Iieggio, is probably connected, by a submarine chain, with the mountains of Africa. The Rhastian Alps stretch between the Grisons and Milan; the Tridentine between the Tyrol and the territories of Venice; the Norican between the Tyrol and Salzburg ; and those of Carinthia between Ca'rinthia, Carniola, Friuli and Istria. On the west, some branches of the Alps extend into France. The Pyrenees form the frontier wall and the principal elevation of the Spanish peninsula. In Africa, the chain called Atlas is the most famous. There is a distinction made between the Great and Little Atlas. The former, which is, perhaps, connected with the mountain chains of Arabia, runs westwardly to Barbary, separating it from Biledulgerid ; the latter reaches from Tunis to Gibraltar. In addition to these, some less celebrated chains extend along the Nile, through Upper Egypt, Nubia and Abyssinia, to unknown regions in the interior of Africa, where they are connected with the Mountains of the Moon. Thence some ridges stretch to the south of Africa, and join, perhaps, the Snow mountains, which take their course from the cape of Good Hope towards the interior. Next to Asia, America contains the highest mountains. With the Cordilleras (q. v.), along the western coast of Chile and Peru, other chains of mountains are connected, running through the rest of South America. One ridge extends through the isthmus of Darien to North America, where it runs nonhward along the western coast, sending off different branches eastward into the interior, which, in all probability, join the mountain ridges of Northern Asia, in the extreme north. The highest known summits are of the Himalaya in Thibet (particularly the Dholagir, or White mountain), which has been made, by one measurement, 26,872 feet, by another 28,015 feet high. The perpendicular height above the level of the sea, of a peak belonging to the Mustag mountains, in Central Asia, measured by the English colonel Crawfurd, is about 26,500 feet; that of Chimborazo, according to Humboldt, 21,440; that of Mauna Kaah, on the Sandwich islands, 18,400; of Cayambourco, 20,000; of Antisana, 19,150; of Pinchinca, 15,940 (all three near Quito); of the farmhouse of Antisana, the highest place inhabited by men, 13,434; of the city of Quito, 9560 ; of Mont Blanc, 15,680 ; of Ophyr, in Sumatra, 13,842 ; of Loucira, in the French department of the Upper Alps, 14,450 ; of Aiguille de 1'Argentine, 12,804; of St. Gothard, 9075; of Mma, 10,936; of Furca, 14,040; of the Brocken, 3716; of the valley of Chamouni, 3463 ; passage of Mont Cenis, 6773; of the city of Geneva, 1220. The heights of these mountains are inconsiderable in proportion to the great mass of the earth, the spherical form of which is not essentially altered by them ; for the height of Chimborazo is not, to the diameter of the earth, in the proportion of 1 to 1000. The form of mountains is generally com cal, that is, gradually tapering from the base upward, and terminating in a more or less pointed peak. The Alps, in Switzerland and Savoy, consist of an enormous collection of different mountains, disposed in several parallel chains. The highest of these chains is in the middle; thoso which rest on them diminish in height in proportion as they recede from the main branch. The highest ridge consists of steep rocks, which, with the exception of the declivities, are every where covered with ice and snow. Between the masses of rocks, that crown the highest chain, in pyramidal forms$ are valleys, in which the snow, and ice proceeding from the halfmelted snow, never thaws, even in summer, because of their high situation. Lower down, on both sides of the main branch, long wide valleys descend, which in summer are decked with a beautiful green, and, where their situation is not too high, are partly planted with corn and fruittrees, partly used for pasturage. To these green vales deep and narrow passages descend from the high rocky valleys. These passages are filled with everlasting ice, and bear the name of glaciers, (q. v.) Those chains of mountains which border on the main chain, present the same appearances, only on a smaller scale ; for their tops likewise consist of pointed rocks, separated by such deep and narrow passages, which, even in summer, are covered with ice and snow, and to which succeed verdant valleys. The farther the chains recede from the main chain, the more do they diminish in height. Every thing bears a milder aspect. The tops of the single mountains are more rounded; the mountains themselves are decked with a beautiful green, and, by degrees, lose themselves in the plains. Countries covered with high mountains present, in the summer, different climates at different elevations, within a very narrow compass. We may ascend gradually from flourishing and delightful valleys, decorated with corn, fruittrees and vines, to pastures covered with odoriferous Alpine plants, and, near the declivities, with evergreens, and perceive the vegetation diminishing and dwindling as we advance, till, at last, all organic life ceases, and the cold prevents all further progress. The elevation of this region of perpetual winter is different in different latitudes; it is higher in warm countries, and lower in cold climates. That the air is colder on the mountains than it is in the plains, is evident from what has oeen said. This is to be attributed partly to the reflection of the sun's rays from the surface of the earth in plains, and its consequent accumulation in the lower strata of the atmosphere, but partly also to the greater density of the air, which is susceptible of being warmed in a higher degree than the thinner air of the mountains. That the air OQ the mountains is purer is certainly true; but that it is healthier also, can be admitted only in regard to a moderate height. At a great height, an indescribable oppression, combined with great weakness, seizes upon the whole bodya phenomenon which Saussure attributes to the diminished pressure of the air upon the vessels, and their consequent loss of elasticity. The interior of mountains is known only so far as it has been laid open to the miner in working mines.See Denaix's Tableau orographique de VEurope (Paris, 1826, 2 vols.); see also the articles Alps, Andes, Cordilleras, Himalaya, &c.