* 457 



the basin of this river seems to be primitively 

 confounded with the basin of another river, that 

 of the Amazon. In casting a look at the map, 

 we see the Upper Oroonoko traverse the same 

 plain from east to west, through which the Ama- 

 zon runs in a parallel but contrary direction ; 

 that is, from west to east. This identity of their 

 basins however is merely apparent ; it must not 

 be forgotten, that the great surfaces of ground, 

 which we call plains, have their valleys like the 

 mountains. Every plain is composed of differ- 

 ent systems of alternate slopes* ; and these sys- 

 tems are found to be separated by ridges, or 

 secondary lines cf elevation, which their small 

 height renders almost Imperceptible to the eye. 

 A continued plain, covered with forests, fills the 

 vast space between 3° SO' of north and 14° of 

 south latitude, between the Cordillera of Parime 

 and that of Chiquitos and of Brazil^. All 

 the waters, as far as the parallel of the sources 

 of the Rio Temi^:, on a surface of two hundred 

 and four thousand square leagues^, flow into the 

 principal recipient of the Amazon ; but farther 

 north, from a particular disposition of the 



* Slopes which incline in opposite directions, with respect 

 to the horizon. 



f See chap. 11, vol. iv, p. 306 - y and the present chap, 

 p. 410. 



X North latitude 2° 45'. 



§ A surface ten times greater than all France, 



