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the Alpine vallies of the Maraguaca, the river 

 runs first toward the west, and west-north-west, 

 as if it were flowing to the South Sea ; when, 

 near the confluence of the Guaviare, it begins to 

 bend toward the north, and follows the direc- 

 tion of a meridian as far as the mouth of the 

 Apure, which is a second point of' count erfiex- 

 ure [i-ebroussement.] In this part of it's course 

 the Oroonoko fills a sort of gutter, formed by 

 the gentle slope which descends from the very 

 remote chain of the Andes of New Grenada, 

 and the very short counterslope rising on the 

 east toward the abrupt side of the mountains 

 of Parime. This disposition of the ground is 

 the cause of the largest tributary streams of the 

 Oroonoko being those of the west. The princi- 

 pal recipient being very near the mountains of 

 Parime, which it turns round from south to 

 north (as if it would run toward Porto Cabello, 

 on the northern coast of Venezuela), it's bed is 

 obstructed by rocks. This is the region of the 

 Great Cataracts ; the river, roaring along, opens 

 itself a passage across the buttresses that project 

 toward the west; so that, in the great land 

 strait* between the Cordilleras of New Grena- 



* (Detroit terrestre.) This is an opening eighty leagues 

 broad, the only one by which the united ba$ins of the Upper 

 Oroonoko and the Amazon communicate with the basin of the 

 Lower Oroonoko, or the Llanos of Venezuela. We consider 

 this opening geologically as a land strait, because it affords a 

 passage to running waters ; and because, without this the 



