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less, grass-covered plains, extending to the foot-hills of the Cordillera de Merida. During high water, the low, flat country looks like a vast lake. The stream is navigable during a part of the year a distance of 1000 miles or more. Unlike the Amazon, the Orinoco has a great delta, and the stream enters the sea through many channels. Under the name of the Rio de la Plata (q.v.) may be included the Uruguay, the Parana, and the Paraguay, with all their tributaries. The plains of Argentina begin on the Amazonian watershed in the highlands of Matto Grosso, Brazil, and in Eastern Bolivia, and following down the valley of the Paraguay pass out of the drainage area of the Parana, properly speaking, and form the flat region lying between the foot-hills of the Andes and the Atlantic Ocean almost to the Strait of Magellan—a length for this plain of more than 2000 miles. The plains in the latitude of Buenos Ayres and from there southward are low, nearly flat on the east side, and rise almost imperceptibly to the lower slopes of the Andes. They are mostly treeless deserts covered with tufts of coarse grass, with here and there shallow pools of salt or brackish water. There are This highland is mostly forest-covered, but there are in many small volcanic peaks and some short mountain ranges over this great plain. the area also large campos or open grass-covered plains. The valley of the Paraguay is here and there heavily The Amazon, the Orinoco, and the Paraguay or La Plata river systems drain an area of 3,686,400 square timbered, in other places it is a treeless or sparselymiles. Less imposing, but yet large and im- covered grassy plain, and in still others it is a hilly, dry, Rivers. p0rtant streams are the Magdalena in Colombia, and thinly-covered campo. The upper Paraguay river the Essequibo in Rritish Guiana, and the Sao 1 rancisco winds through grass-covered, meadow-like plains apparin Brazil. The Amazon (properly the Rio das Amazonas ently as flat and boundless as the sea. Above this plain or river of the Amazons) and its tributaries is not only rise a few isolated peaks, like so many islands in a great the largest river in South America, but by far the largest lake. Only above the navigable portions of the stream, in the world (y.'W.) The total navigable length of the main i 1700 miles from its mouth, does it flow through a hilly stream, from Para to the head of the navigation on the country. A noteworthy feature of the tributaries of the Huallaga in Peru, is 3000 miles. This does not include Paraguay is that many of those flowing down from the the hundreds of equally navigable parallel side channels region of the Andes are more or less brackish, while the that accompany the main stream from its mouth almost Uruguay and Parana and their tributaries entering from to the mouth of the Javary. Above the falls, again, all the rainy, forest-covered regions of Brazil, are all freshthese streams are navigable for long distances. The river water streams. The Sao Francisco is the largest river that lies wholly is nowhere confined to a single channel, but its waters in Brazil. It rises in the highlands not far from the spread over an enormous flood-plain and flow with a sluggish current through thousands of side channels that coast in latitude 21° and flows north-east parallel with the anastomose with each other so that it is impossible for coast until it reaches latitude 9° 30', where it bends one not familiar with the stream to distinguish the main sharply to the right and enters the Atlantic 360 miles channel. In several places the river is. so wide that one south of Cape St Roque. It is navigable in its lower looking across it sees a water horizon as if he were looking course, but at a distance of 140 miles from its mouth the out over the ocean. Indeed much of the region is more falls of Paulo Aflbnso, the “ Niagara of Brazil,” interrupt like a great freshwater sea filled with islands than it is all navigation. The upper part of the river, however, is like a valley with a stream running through it. For the navigable for a long distance. Throughout its entire most part the land along the river is low, flat, and marshy, length it flows through a hilly or mountainous country. The Rio Magdalena in Colombia is a crooked, muddy and under water a part of the time; but at a few places, stream entering the sea through two mouths; it is navinotably at Erere, Obidos, Velha Pobre, Paru Paraua-quara, gable up to Honda (862 feet above tide-level) and has a and Almeirim table-topped hills are visible from the river. length of 2000 miles. Above the mouth of Rio Cauca, The banks of the stream and of its side channels are every- the mountains are visible on both sides of the river. where lined with a dense forest. The valley, however, is There are remarkably few freshwater lakes in South not all forest-covered. Beginning near the Oyapok on America, and most of these are in the Andes mountains. the Guiana frontier, a series of dry sandy campos or open Lake Titicaca, near La Paz in Bolivia, is, in ^aAes grassy plains, interrupted by wooded river banks, follow respect of elevation and position, the most realong the north side of the river for about 700 miles. markable lake of its size in the world. Its surface has an The Upper Amazon valley opens broadly towards the elevation of 12,545 feet, it covers an area of between north-east and descends to the sea through the Orinoco, and 5000 square miles, has a maximum depth of while towards the south the Madeira basin, tin oug one o 4000 700 feet, and never freezes over. Titicaca discharges into its upper branches—the Guapore—unites with the basin of another shallow lake or marsh which is supposed to have the Paraguay. _ outlet. Lake Junin or Chinchaicocha on the plateau The Orinoco proper (q.v.) rises in the highlands between no east of Lima in Peru has an area of 200 square miles, Brazil and Venezuela, by a broad curve swings around the and an altitude of 13,380 feet. Along the eastern western end of these highlands, and then for 400 miles base of the Andes, in Southern Argentina, is a series flows east into the Atlantic. Along its lower course the of lakes whose basins were probably formed, by the banks are covered with heavy forests. _ In its upper course glaciers that formerly flowed down to the plains from the mountainous highlands are visible along its right the mountain ranges. There are many lakes over the bank, while on its left are enormous stretches of flat, treeS. L — 47

There is an elevated region near the eastern corner of the continent on the watershed between Rio Sao Francisco, Rio Jaguaribe, and Rio Parahyba do Norte. This watershed is not a mountain range, but a broad and broken plateau with an elevation of about 3000 feet, and with individual peaks reaching 4000 feet above tide level. North of the mouth of the Amazon the coast is low, much of it is swampy, and all of it is forest-covered as seen from the ocean. This low coast extends across the Guianas and Venezuela as far as the headland north of the Gulf of Paria, where the Merida or Venezuelan branch of the Andes reaches the sea. Along this Guiana coast is a belt of low wooded land, beyond which the streams are not navigable save by canoes. The highlands south of Venezuela and the Guianas, and north of the Amazon valley, form a broad plateau, above which rise several high peaks. The known peaks are :— 8740 feet. Roraima. 8500 ,, Duida 8230 ,, Maraguaca 6000 ,, Turagua.