456 



rivers is, that, on issuing from the mountains, 

 they pursue a course parallel to the chain. The 

 plains, the slopes of which rise toward the moun- 

 tains, take irregular forms at their feet. The 

 nature of these foliated rocks, and the direction 

 of the strata, parallel to the direction of the 

 great chains, may often be the cause of the phe- 

 nomenon we are discussing : but the granite of 

 the Sierra Parime, being almost always in mass, 

 and not stratified, the proximity in which the 

 Oroonoko follows the outlines of this group of 

 mountains indicates a depression of the ground, 

 which arises from a greater geological pheno- 

 menon, from a cause connected perhaps with 

 the formation of the Cordilleras itself. In in- 

 land seas and lakes, the deepest places are 

 those, where the coast is most elevated and 

 abrupt. When we descend the Oroonoko from 

 Esmeralda to Angostura, whether our course 

 be toward the west, the north, or the east, in 

 a distance of two hundred and fifty leagues, 

 we always perceive very lofty mountains on 

 the right bank ; and plains, that extend as far 

 as the eye can reach, on the left. The line of 

 the greatest depths, of the maxima of depres- 

 sion, is consequently found at the very foot of 

 the Cordillera, on the circumference of the 

 Sierra Parime. 



Another peculiarity in the course of the Oroo- 

 noko, which strikes us at the first view, is that 



