CHAMBERS'S INFORMATION FOR THE PEOPLE. 



extremities are fertile, and the middle sandy and 

 arid. 2. The basin of the Orinoco, consisting of 

 extensive plains called llanos, covered with high 

 herbage. 3. The basin of the Amazon, a vast 

 plain of more than 2,000,000 square miles, with a 

 rich soil and humid climate, and covered with 

 dense forests. 4. The valley of the Plata, occu- 

 pied by plains called pampas, in some parts 

 barren, but in general covered with weeds, thistles, 

 and tall grasses, on which feed prodigious herds 

 of wild horses and cattle. 5. The high country of 

 Brazil, eastward of the Parana and Uruguay, pre- 

 senting alternate ridges and valleys, covered with 

 wood towards the Atlantic, but opening into 

 grassy steppes in the interior. 6. Patagonia, con- 

 sisting of a succession of terraced plains called 

 pampas, often sterile, but containing large tracts 

 covered with coarse grass, shrubs, and thistles, 

 the home of large numbers of guanacos, ostriches, 

 pumas, armadillos, &c. 



Two systems of mountains the Cordilleras or 

 Andes Proper, and the Brazilian Andes traverse 

 the continent The former extend from the Strait 

 of Magellan to the Caribbean Sea, embracing 

 lofty table-lands and mountain-lakes, and inter- 

 sected by steep valleys, ravines, and water-falls. 

 At Popayan, the main chain divides into three 

 ridges, one of which shoots off into the Isthmus 

 of Panama ; a second separates the valleys of the 

 Cauca and Magdalena ; and a third divides the 

 valley of the Magdalena from the plains of the 

 Meta. The chain attains its greatest elevation in 

 Chili, where Aconcagua, the highest summit of 

 the Andes, and the highest known volcano in the 

 world, rises to 22,296, and the mountain-passes 

 are seldom under 12,000 feet. In the Bolivian 

 Andes, Illimani and Sorata are respectively 21,181 

 and 21,286 feet high. The Peruvian and equa- 

 torial portions of the chain are less elevated. 

 Altogether, the Andes present a most magnificent 

 spectacle their lofty summits permanently snow- 

 capped, and vast volumes of smoke and fire being 

 occasionally poured forth from the numerous 

 volcanoes which stud the entire range. The 

 Brazilian Andes occupy a greater breadth of 

 country, but seldom exceed an elevation of 6000 

 feet. 



The resemblance of the geology of South 

 America to that of North America is so close, 

 that it is hardly necessary to enter into details, 

 and for a conception of its general character, the 

 reader is referred to the previous number. It may 

 here be noticed, that those crystalline rocks which 

 occupy the vast region between the Great Lakes 

 and the Arctic Ocean, also stretch over nearly the 

 whole of the eastern portion of South America, 

 extending from its northern shores to the mouth 

 of the La Plata, though hidden in the valley of 

 the Amazon by its alluvial deposits. On the other 

 hand, the Silurian system is only slightly developed 

 on the eastern slopes of the Andes. The Tertiary 

 formation occupies a large amount of the surface. 

 From Patagonia to Venezuela it can be traced 

 throughout the space intervening between the base 

 of the Andes and the azoic rocks of Brazil and 

 Guiana. The older Silurian and carboniferous 

 deposits are not found in the same positions as in 

 the northern continent : the gneiss, &c. dip directly 

 under the Tertiaries. The valleys of the Amazon 

 and the La Plata contain extensive alluvial de- 

 posits. Post-tertiary beds occur in Patagonia and 



322 



the pampas of the Argentine Confederation, and 

 are covered with a deposit of clay and sand, con- 

 taining the bones of the megatherium and mylodon, 

 genera allied to the sloths, and of the glyptodon, a 

 huge armadillo. 



HYDROGRAPHY, ETC. 



The islands, capes, straits, gulfs, &c. connected 

 with this continent present no very remarkable 

 features. The chief islands are the alluvial flats 

 in the estuary of the Amazon; the Falkland and 

 Georgian groups on the south-east ; the desolate 

 and rugged archipelago of Tierra del Fuego ; 

 the memorable islet of Juan Fernandez, off 

 the coast of Chili ; and the Galapagos in the 

 Pacific. The more prominent capes are St 

 I Elena and Blanco on the west, Cape Horn on 

 the south, and Frio and St Roque on the east 

 I Among the bays and gulfs which indent the coast 

 are the Bay of Panama on the west of the 

 isthmus ; and the Gulf of Darien on the east ; 

 the estuaries of the Amazon, the La Plata, and the 

 Orinoco ; the Bay of All Saints ; and the Gulfs 

 of Guayaquil and Maracaybo. The principal 

 strait is that ef Magellan, about 300 miles long, 

 with a breadth varying from i to 40. 



The rivers of South America, like its other 

 features, are on the grandest scale. The areas 

 drained by the Amazon (the largest river in the 

 world), the La Plata, and the Orinoco, are re- 

 spectively 2,000,000, 1,250,000, and 400,000 square 

 miles in extent, while their respective courses 

 ' are 4000, 2400, and 1960 miles in length. The 

 \ Amazon, with its tributaries, gives 50,000, the 

 : La Plata 20,000, and the Orinoco 8000 miles of 

 1 boat-navigation. Not to speak of such import- 

 | ant affluents as the Parana, the Paraguay, and 

 the Salado, which flow into the La Plata, many 

 of the tributaries of the great rivers of this con- 

 tinent, which are seldom named even in maps, 

 are larger than the largest of European rivers. 

 The other independent rivers worthy of note are 

 the Magdalena, Tocantins, Parnaiba, San Fran- 

 cisco, Uruguay, and Colorado. In the high table- 

 land of Bolivia and Peru, are several fresh-water 

 lakes, the largest of which, Titicaca, at an altitude 

 of 12,700 feet, covers an area of 5000 square 

 miles. The salt lakes of La Plata are also of con- 

 siderable size, but so shallow, that many of them 

 are annually dried up, leaving incrustations of 

 common salt, nitrate of soda, and the like, which 

 are of considerable economical importance. 



CLIMATE BOTANY ZOOLOGY. 



South America is sharply defined into three 

 zones of temperature the frigid, the temperate, 

 and the torrid ; but, as this division originates 

 in the enormous difference of level of its various 

 regions, and not in difference of latitude, the 

 temperature is almost uniform throughout the 

 year, and the salutary vicissitudes of the seasons 

 are wanting. Not the intensity, but the continu- 

 ance of cold in the frigid, and of heat in the torrid 

 zone, renders these regions unhealthy ; while the 

 moderate and constant warmth of the temperate 

 zone excludes from it all but its own peculiar 

 plants and animals, which can live neither above 

 nor below its limits. In the words of Malte Brun : 

 ' The summer, the spring, and the winter are here 



