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MOUNTAIN Haymakers,' of which are in private galleries m JN ew i orK, and "Bargaining for a Horse," in the New York historical society's collection. He ex- celled especially in humorous pictures of Amer- ican rustic life, and in delineations of negro life and physiognomy. MOUNTAIN, a considerable elevation, of the earth's surface, either isolated or arranged in a linear manner. Great regions of the earth are much elevated above the sea, forming high plains, called table lands or plateaus, from which mountains often rise. Such are the great plain of Thibet, with an average height of 16,000 ft. ; that of western Asia, from 4,000 to 8,000 ; and that of western North America, of about the same height, from which rise the Rocky mountains and the Sierra Nevada. The elevation of mountains is generally calculated from the sea level. With few exceptions the mountains of the earth are arranged in con- tinuous lines or chains, and a mountain system consists of parallel chains with intervening val- leys. The great mountain system of the Ame- rican continent is that which has been called the Pacific highlands, extending from Alaska to Cape Horn along the W. part of the conti- nent. It consists in the United States, exclu- sive of Alaska, of the Rocky mountains to the east and the Sierra Nevada and Cascade moun- tains to the west, rising from the broad table land already mentioned, and having between them the great central basin with its subordi- nate mountain ranges. The highest points in both of these chains attain about 15,000 ft. The highest mountains in Alaska (Mt. St. Elias) and Mexico (Popocatepetl and Orizaba) rise to a height of nearly 18,000 ft. In South Amer- ica the same great continental system consists of two, and in some parts of its course of three chains, separated by narrow elevated valleys. The general breadth of the whole system of the Andes is between 100 and 300 m., and the greatest height is attained in the plateau of Bolivia and in Chili, where there are peaks of from 20,000 to 23,000 or, according to some, 25,000 ft. In eastern North America are the Atlantic highlands or Appalachians, extending from the gulf of St. Lawrence to Alabama; these attain their greatest elevation 'in the Black mountains of western North Carolina, where there are several peaks of over 6,000 ft., one reaching 6,700 ft., and in New Hampshire, where the highest, Mt. Washington, is 6,285 ft. In the intermediate portions the heights are less, and in New York the tidal valley of the Hudson traverses the range. To the north and west of the Hudson are the Adirondack, Helderberg, and Catskill mountains, which in their continuation southward form the Al- leghany and Cumberland mountains. Be- tween this belt and the eastern one, which, extending from the Green mountains and White mountains of New England, and the Highlands of the Hudson, takes the name of the Blue Ridge S. of the Potomac, lies what is called the great Appalachian valley, which itself attains a considerable elevation in S. W. Virginia. From the plateau of Brazil rises along its E. portion a chain corresponding to the Appalachian; and in Africa there are similar highlands on the two sides of the con- tinent, those of the eastern attaining an ele- vation of 20,000 ft. A like arrangement of highlands is seen in Australia, where however the highest elevation is about 7,000 ft. In Europe the Scandinavian and the Ural moun- tains are N. and S. chains, like the Appala- chians ; but the great mountain systems of the eastern hemisphere have a general E. and W. direction from the Atlantic to the Pacific. The Pyrenees, the Alps, the Balkan, the Caucasus, the Himalaya, and various subordinate ranges, mark this great mountain belt. Of these the Pyrenees have a crest line of about 8,000 ft., but attain in some peaks 11,000; the Alps have an average height of from 10,000 to 12,000 ft., the highest peak being Mont Blanc, 15,732 (or 15,781) ft., while the Himalayas rise in many points to 25,000 ft., and attain in Mt. Everest 29,000 ft., and the Thian-shan range, N. of these, is from 15,000 to 20,000 ft. The chains of this great mountain region of the eastern hemisphere are not always parallel, but are often considerably divergent. The slopes of mountains are generally very grad- ual. Thus the average ascent of the Andes from the E. side is about 60 ft. in a mile, and on the bolder W. slope from 100 to 150 ft. in a mile ; while for the E. slope of the Rocky mountains the average ascent to the great pla- teau is not more than 10 ft. in a mile. A much more rapid inclination than any of these is seen for isolated peaks, of which a very remarkable sample is Mont Blanc, which rises from the valleys on either side at an inclina- tion of about 30. The slope of the volcanic cone of Jorullo in Mexico is about the same, while those of Mt. Etna and Mauna Loa in the Hawaiian islands (reckoning from the base) are not more than 5 or 6. The relations of mountains to climate are very important, but the discussion of them belongs to meteorology. The early history of mountains, or orography, as it is called, presents crude notions. By the older geologists mountains were supposed to be thrust up by some force from within, and were compared to bubbles on the earth's crust. Some geologists of the present century have maintained this notion, and have even specu- lated upon the cataclysmal effects of a sudden upheaval of a mountain chain like the Pyrenees from beneath the ocean. But these concep- tions have given place to more rational ideas. We must distinguish two classes of mountains, of widely different origin: those which are produced by the accumulation of matters eject- ed from volcanic vents, and those which have been formed by erosion. The first class, of