« PreviousContinue »
Bolivia and Ecuador to Colombia. The Cordilleras and the Andes are connected in several places by knots or cross-chains of mountains. In Colombia the Andes turn to the northwest, reaching their lowest elevation at the Panama canal, and continue thence, through Central America and North America as the Rocky Mountains, to the Arctic ocean. Near the source of the Magdalena and Cauca rivers in Colombia, the eastern range is deflected to the east along the northern coast of South America. The central range disappears between the Magdalena and Cauca rivers.
The Andes form the water-shed of the continent. The waters on the western slope flow into the Pacific ocean. The rivers that rise on the eastern slope, in northern Peru and Ecuador, force their way through the Cordilleras and at their foot drain the montaña of Bolivia, Peru and Brazil. In the southern part of Peru and upper Chili there is a broad sierra or plateau, at an elevation of from twelve to fourteen thousand feet. The streams that rise in this sierra either empty into salt or alkaline lakes or sink into the ground.
Unlike all other long ranges of mountains, the continental or eastern side of the Cordilleras is nearly as precipitous as that extending to the Pacific. Craters of extinct volcanoes and volcanoes now in eruption are found in all parts of the chain. In Ecuador there are fifty-two volcanoes, and twenty of these, covered with perpetual snow and presided over by Chimborazo and Cotopaxi, rise out of a group of mountains encircling the valley of Quito, and are all visible from a single point. Three are active and five others have been in eruption at one or more times since the conquest. One of these, Sangai, is the most active volcano on the globe : it sends forth a constant stream of fire, water, mud and ashes, and some assert that it has done so without intermission for 300 years ; 267 explosions have been counted in one hour. This is also the land of earthquakes : in 1868, 50,000 lives, we are told, were lost in one day ; the tremor was felt over four countries and fron the Andes to the Sandwich Islands. The tidal wave washed a gunboat of the United States on shore at Arica in lower Peru, 1000 miles to the south, and sixteen hours later the wave was felt across the Pacific at New Zealand.
A range of mountains separates Eastern Venezuela and Guiana from the valley of the Amazon. Other ranges south of the Amazon run southwestwardly, following the Atlantic coast line from Cape St. Roque to the Rio de la Plata.
RIVER SYSTEMS. A great oceanic current flows along the western coast of Africa to the equator, where it is deflected across the Atlantic ocean and becomes the equatorial current. On reaching the coast of South America near Cape St. Roque, it is again deflected north and south. Trade winds blowing over the equatorial current reach the coast at Brazil surcharged with vapor; as they follow up the valley of the Amazon the vapors are partially condensed and frequent showers refresh the land ; but when the clouds at the foot
l bills of the Andes meet the colder winds from the south and strike the snow summits of the Cordilleras, all the moisture is condensed, and the rain falls in tropical showers for half the year and waters the largest and richest valley in the world.
In this valley, among the Cordilleras, three great rivers—the Orinoco, the Amazon and La Plata-rise. The mountain ranges north and south of the Amazon divide this great valley into three lesser valleys, down which the Orinoco, the Amazon and La Plata flow, watering three-fourths of South America.
The Orinoco. The headwaters of the Orinoco rise in two ranges of mountains; the Cordilleras in the west, and the mountains of Venezuela many hundred miles to the east. Four hundred tributaries, abounding in beautiful falls and cataracts, unite to form this
The whole valley for 1600 miles is filled with dense and tangled forests. Noble trees of unrivalled beauty blossom in endless prodigality. Birds of gorgeous plumage nestle in their lofty
Tall ferns, vines, creeping plants and parasites form a dense tangle of undergrowth, swarming with life. Myriads of insects in great variety, reptiles of strange and singular form, lizards and venemous serpents find their homes and sustenance in the wild, dense mass of vegetation.
The Amazon. The valley of the Amazon collects its waters from a region 1800 miles wide from north to south and 2500 miles long from the Andes to the Atlantic ocean. Even at the foot of the Andes the Amazon is a mighty river. The valley rapidly narrows to a width of 600 or 700 miles, and then more gradually to the ocean, where it is only 150 miles wide. Its total fall from the foot-hills of the Andes to the Atlantic is very slight, not over three or four hundred feet, and probably considerably less.
The rims of the valley are formed of diorite and sandstone, and are raised only a little above the flood-plain, which is formed of mud and silt, the detritus brought down by the Amazon and its tributaries. The flood-plain is from fifty to one hundred miles wide, gradually narrowing as it approaches the ocean. Through this valley the Amazon cuts its way, separating often into channels which sometimes run parallel to each other for several hundred miles, frequently forming large islands, or expanding into lakes. Similar flood-plains are found on all its larger tributaries.
Up from the ocean into this valley an immense tidal wave rolls, with a bore, twice a day, forcing back the current of the Amazon 500 miles and inundating a portion of the flood-plain.
In the early autumn the equatorial rise commences in the headwaters of its tributaries, far south of the equator. The rains and melting snow raise the streams, and these the waters of the Amazon. As the sun crosses the equator and moves to the north the rain follows its course, and the branches that have their source in the east and northeast add their food to the waters of the southerly branches. The flood in the Amazon is thus continued for nearly six months, raising its waters from 30 to 50 feet. The channels are filled, and the flood-plains are overflowed. The whole valley becomes a net-work of navigable waters, with islands and channels and lakes innumerable, forming a great inland sea, which the Brazilians call the Mediterranean of America. The upland, though only a little above the flood-plain, is rarely overflowed.
The plants and animals of the flood-plain were formerly considered as distinct from those of the upland as are the plants and animals of Europe from those of America ; but later investigations show that there is but little difference between the species.
The sea breeze blows up the valley about a thousand miles. Then for 1500 miles the atmosphere is stagnant and sultry ; the climate is that of a permanent vapor bath. The dense foliage forms dark, lofty vaults which the sunlight never penetrates, and over all hangs a perpetual mist. The abundance and beauty of vegetation increases, and the trees which at the mouth of the river blossom only once a year, here bloom and bear fruit all the
Many great rivers run into the Amazon from the north and the south, most of them navigable, for many hundred miles. The Madeira, its greatest tributary, after running 2000 miles, empties into the king of rivers, without making any perceptible difference in its width or depth.
This mighty current, rushing into the ocean, meets the equatorial current and for over one hundred miles keeps on nearly a straight course, when the stronger and mightier oceanic current deflects it to the north. At from 200 to 300 miles from land, the sea is strongly tinged, and in April and May has nearly the clayyellow hue of the Amazon. And even further north, about 400 miles from its mouth, the naturalist on the Amazon tells us, passed numerous patches of floating grass mingled with tree trunks and withered foliage; among these I espied many fruits of the Amazonian palm. And this was the last I saw of the Amazon."
The Rio de la Plata.
The La Plata, the outlet of the waters of central South America, is formed by the union of the Uruguay and Parana, about 150 miles from the ocean ; a little lower down, at Montevideo, it is 62 miles wide and widens rapidly to the Atlantic, where it discharges more water than all the rivers of Europe. The tributaries of the Parana are fan-shaped. Its most eastern branches rise in the mountains of Brazil, within seventy miles of the Atlantic ocean; and 1500 miles away, on the other side of the continent, its most western tributaries rise only 125 miles from the Pacific.
Steamers ascend the Parana, Paraguay and Cuyaba, 2100 miles to Cuyaba, and the river with its branches is navigable for 5000 miles.
The San Francisco.
The San Francisco, about 1800 miles long, rises near Rio de Janeiro and flows north about 1200 miles between parallel ranges of mountains, then turns east and forces its way through the coast range to the Atlantic ocean. It runs through the gold and diamond regions of Brazil, and has a considerable population along its banks. It has many falls and rapids, and considerable slack-water navigation.
In Asia, the different countries have natural boundaries ; the people, soil and climate of one country are unlike those of others. In Europe there are few natural boundaries, though different races inhabit the several states.
In South America only one dominant race is found, and though natural boundaries exist, yet they do not serve as boundaries to the different states, other than Venezuela and Guiana. Venezuela and Guiana are watered by the Orinoco and by several rivers that flow from the Amazonian mountains to the ocean. The whole coast is low and fertile, but hot and unhealthy. The principal product is sugar, raised by negroes and coolies. The interior is sultry and thickly wooded ; it is inhabited by Indian tribes, the principal of which are the cannibal Caribs, and by negroes as uncivilized as any of the tribes in Africa. Guiana is controlled by the English, French, and Dutch. Cayenne, the prison for French convicts, is the capital of French Guiana.
Colombia and Ecuador occupy the northwestern part of South America. They are situated on both sides of the Andes, and have every variety of climate. The country is well watered ; fertile but unhealthy on the coast, fertile and healthy on the elevated plains, cold and barren on the mountains.
In Brazil, besides the Amazon, La Plata and San Francisco, there are several large rivers with fertile valleys ; but occasional droughts, sometimes lasting for two years, will prevent portions of Brazil from becoming densely inhabited.
On the Pacific coast south of Ecuador, the rainfall becomes less and less. For three thousand miles along the coast of Peru and Chili there is no natural harbor ; a plain from ten to fifty miles in width extends from the Pacific to the foot-hills of the Andes. The Antarctic current runs along this coast; the southeasterly winds blow over it on to the land and cool the air; but as the winds are of low temperature their scanty vapor is dissipated by the heat radiated from the land, and not a drop of rain refreshes the thirsty soil. Many mountain torrents run from the snow-clad summits of the Andes, and the beauty of their narrow valleys forms a grateful contrast to the dry and barren sands of the plain.
In the southern part of Chili and in that part formerly called Patagonia, rain is abundant and the country is fertile.
The longest stretch of low and comparatively level land to be