Drainage-ways of South Ainerica. 3 



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 equatoi'ial current reach 

 the coast at Brazil surcharged with vapor ; as they follow up the 

 valley of the Amazon the vapors are partially condensed and fre- 

 quent showers refresh the land ; but when the clouds at the foot- 

 hills of the Andes meet the colder winds from the south and 

 strike the snow summits of the Cordilleras, all the moistui-e 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 moun- 

 tains ; the Cordilleras in the west, and the mountains of Vene- 

 zuela many hundred miles to the east. Four hundred tributaries, 

 abounding in beautiful falls and cataracts, unite to form this 

 great river. 



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 

 recesses. 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, 



