The Start 7 



tory is Brazilian. Aside from certain relatively small 

 stretches drained by coast rivers, this immense region of 

 tropical and subtropical America east of the Andes is 

 drained by the three great river systems of the Plate, 

 the Amazon, and the Orinoco. At their headwaters the 

 Amazon and the Orinoco systems are actually connected 

 by a sluggish natural canal. The headwaters of the 

 northern affluents of the Paraguay and the southern 

 affluents of the Amazon are sundered by a stretch of 

 high land, which toward the east broadens out into the 

 central plateau of Brazil. Geologically this is a very 

 ancient region, having appeared above the waters before 

 the dawning of the age of reptiles, or, indeed, of any 

 true land vertebrates on the globe. This plateau is a 

 region partly of healthy, rather dry and sandy, open 

 prairie, partly of forest. The great and low-lying basin 

 of the Paraguay, which borders it on the south, is one 

 of the largest, and the still greater basin of the Amazon, 

 which borders it on the north, is the very largest of all 

 the river basins of the earth. 



In these basins, but especially in the basin of the 

 Amazon, and thence in most places northward to the 

 Caribbean Sea, lie the most extensive stretches of tropi- 

 cal forest to be found anywhere. The forests of tropical 

 West Africa, and of portions of the Farther-Indian re- 

 gion, are the only ones that can be compared with them. 

 Much difficulty has been experienced in exploring these 

 forests, because under the torrential rains and steaming 

 heat the rank growth of vegetation becomes almost im- 

 penetrable, and the streams difficult of navigation; while 

 white men suffer much from the terrible insect scourges 



