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 ANDERSONYILLE—ANDES which was opened to women in 1877. In 1897 Mrs Garrett Anderson was elected president of the East Anglian branch of the British Medical Association. The movement for the admission of women to the medical profession, of which she was the indefatigable pioneer in England, has extended not only to every part of the United Kingdom and the British colonies, but to every European country except Spain and Turkey. Andersonville, a village of Sumter county, Georgia, U.S.A., on the Central of Georgia railway. During the Civil War it was the site of a Confederate prison for Ecderal soldiers. It is now the site of a national cemetery. Andes.—The Andes form a continuous chain of mountainous highland along the western coast of South America, which, roughly speaking, may be regarded as 4400 miles long, 100 miles wide in some parts, and of an average height of 13,000 feet. The connexion of this system with that of the Rocky Mountains, which has been pointed out by many writers, has received much support from the discovery of the extensive eruptions of granite during Tertiary times, extending from the southern extremity of South America to Alaska. The Andean range is composed of two great principal chains with a deep intermediate depression, in which, and at the sides of the great chains, arise other chains of minor importance, the chief of which is that called the Cordillera de la Costa of Chile. This starts from the southern extremity of the continent, and runs in a northerly direction, parallel with the coast, being broken up at its commencement into a number of islands, and afterwards forming the western boundary of the great central valley of Chile. To the north this coastal chain continues in small ridges or isolated hills along the Pacific as far as Colombia, always leaving the same valley more or less visible to the west of the western great chain. These mountains were the objects of important investigations during the last quarter of the 19th century. Of the two principal chains, the eastern is generally called Los Andes, and the western La Cordillera, in Colombia, Peru, and Bolivia, where it is likewise known as Cordillera Real _de Los Andes, whilst to the south of parallel 23° S. lat. in Chile and Argentina, the western is called Cordillera de los Andes. The eastern disappears in the centre of Argentina, and it is therefore only the Cordillera de los Andes that is prolonged as far as the south-eastern extremity of the continent. The Cordillera de la Costa begins near Cape Horn, which is composed principally of crystalline rocks, and its heights are inconsiderable when compared with those of the true Cordillera of the Andes. The latter, as regards its main chain, is on the northern coast of Beagle Channel, in Tierra del Fuego, bounded on the north by the deep depression of Lake Fagnano and of Admiralty Sound Staten Island appears to be the termination to the east. The Cordillera of the Andes in Tierra del Fuego is formed of crystalline schists, and culminates in the snow-capped peaks of Mount Darwin and Mount Sarmiento (7200 feet), which contains glaciers of greater extent than those of Mont Blanc. Sir Martin Conway recently ascended the latter. The extent of the glaciers is considerable in this region, which, geographically, is more complex than has hitherto been supposed. Although, in the explored portion ol the Fuegian chain, the volcanoes which have been mentioned irom time to time have not been met with, there seems to have existed to the south, on the islands, many neo-volcanic rocks, some ot which appear to be contemporaneous with the basaltic sheet that covers a part of Eastern Patagonia. The insular region between Mount Sarmiento and the Cordillera de los Andes, properly so called, i.e., that which extends from Magellan Strait northwards, has not been explored, and all that is known of it is that it is principally composed of the same rocks as the Fuegian section, and that the greater part of its upper valleys is occupied by glaciers that reach down to the sea amid dense forest. As Admiralty Sound and Lake Fagnano, the extent ot which is still unknown, bound the Cordillera to the north in Iierra del Fuego, so at the eastern side of the Cordillera in Patagonia there is a longitudinal depression which separates the Andes from some

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independent ridges pertaining to a secondary parallel broken chain called pre - Cordillera. This depression is occupied in a great part by a series of lakes, some of these filling transversal breaches in the range, whilst others are remains of glacial reservoirs, bordered by morainic dams, extending as far as the eastern tableland and corresponding in these cases with transversal depressions which reach the Atlantic Ocean. Between the larger lakes, fed by the Andine glaciers of the eastern slope of the Southern Andes, are Lakes Maravilla, 100 square miles, and Sarmiento, 26 square miles, 51° S. lat., which overflow into Last Hope Inlet; Argentino, 570 square miles, 50° S. lat. ; and Yiedma, 450 square miles, 49° 30' S. lat., which empty into the river Santa Cruz ; the fiordian Lake San Martin, 49° S. lat.; and Lakes Nansen, 18 square miles ; Azara, 8 square miles ; and Belgrano, 18 square miles, which are dependants of Lake San Martin (380 square miles), and Lakes Pueyrredon (98 square miles) and Buenos Aires (700 square miles), and which now overflow into the Pacific, through one of the remarkable inlets that are found throughout the Cordillera, the Calen Inlet, which is the largest western fiord of Patagonia. To the north of Lake Buenos Aires there is Lake Elizalde, which, while situated on the eastern slope sends its waters to the Pacific Ocean, and Lakes Fontana (30 square miles) and La Plata (34 square miles), 45° S. lat., which feed the river Senguerr, which flows to the Atlantic. Lake General Paz (66 square miles) on the eastern slope of the Andes, at 44° S. lat., is the principal source of the Palena river, which cuts all the Cordillera, while Lakes Fetalauquen (20 square miles), Menendez (28 square miles), Rivadavia (10 square miles), and other smaller lakes, also situated between 43° 30', and 42° 30' S. lat. on the eastern slope, send their waters to the Pacific by the river Fetaleufu, which cuts through the Andes by a narrow gorge. The waters of Lake Puelo (18 square miles) likewise flow into the same ocean through the river of that name, which also cuts the Cordillera, and of which the principal affluent likewise drains the waters of a system of small lakes, the largest of which, Lake Mascardi, measures 17 square miles, which in comparatively recent times formed part of the basin of Lake Nahuel-Huapi (207 square miles), 41° S. lat. An extensive area of glacial deposits shows that a sheet of ice formerly covered the whole eastern slof>e to a great distance from the mountains. To the west another sheet reached at the same time the Pacific Ocean. From the Strait of Magellan up to 52° S. lat., the western slope of the Cordillera does not, properly speaking, exist. Abrupt walls overlook the Pacific, and great longitudinal and transversal channels and fiords run right through the heart of the range, cutting it generally in a direction more or less oblique to its axis, the result of movements of the earth’s crust. The mountains forming the Cordillera between Magellan Strait and 41° S. lat. are higher than those previously mentioned in Tierra del Fuego. Generally composed of granite, gneiss, and Palaeozoic rocks, covered in many parts by rugged masses of volcanic origin, their general height is not less than 6500 feet, while Mount Geikie is 7500 feet and Mount Stokes 7100 feet high. To the north are Mounts Mayo, 7600 feet; Agassiz, 10,600 feet; and Fitz Roy, in 49° S. lat., 11,120 feet high. The section from 52° to 48° S. lat. is a continuous ice-capped mountain range, and some of the glaciers extend from the eastern lakes to the western channels, where they reach the sea-level. The level of the lakes commences at 130 feet at Lake Maravilla and gradually ascends to near 700 feet at Lake San Martin. Passing the breach through which Lake San Martin empties itself into Calen Inlet, in 48° S. lat., is found a wide oblique opening in the range, through which flows the river Las Heras, fed by Lake Pueyrredon, which is only 410 feet above the sea-level to the east of the Andes, while Lake Buenos Aires, immediately to the north, is 710 feet. The Andes continue to be to the west an enormous rugged mass of ice and snow of an average height of 9000 feet, sending glaciers to all the eastern fiords. Mount San Lorenzo, detached from the main chain in the preCordillera, is 11,800 feet high. Mount San Valentin, 12,700 feet, is the culminating point of the Andes in the region extending from 49° to 46° S. lat., where another breach occurs, that of the river Huemules, which is supposed to be the outlet of Lake Elizalde to the east, and is followed by that of the river Aysen. These two breaches have emptied a large system of lakes, which, in pre-Glacial times, occupied the eastern zone, thus forming a region suitable for colonization in the broad valleys and hollows, where the rivers, as is the case with those in the north, cut through the Andes by narrow gaps, forming cataracts and rapids between the snowy peaks. Volcanic action is still going on in these latitudes, as the glaciers are at times covered by ashes, but the predominant rocks to the east are the Tertiary granite, while to the west gneiss, older granite, and Pakeozoic rocks prevail. The highest peaks, however, seem to be of volcanic origin. Farther north, up to 41° S. lat., the water gaps are situated at a lesser distance one from the other, owing mainly to S. I. — 54