CATABACTS OF THE ORINOCO. 169 



When M. Bonpland and myself were returning from the 

 banks of the Rio Negro, we ventured to pass the latter, that 

 is the lower half, of the Raudal of Atures in our loaded 

 canoe. We several times disembarked to climb over rocks, 

 which, like dykes, connected one island with another. At 

 one time the water shoots over these dykes ; at another it falls 

 into their cavities with a deafening hollow sound. In some 

 places considerable portions of the bed of the river are per- 

 fectly dry, in consequence of the stream having opened for 

 itself a subterranean passage. In this solitude the golden- 

 coloured Rock Manakin (Pipra rupicola) builds its nest. 

 This bird, which is as pugnacious as the East India cock, 

 is one of the most beautiful birds of the tropics, and is re- 

 markable for its double moveable crest of feathers with which 

 its head is decorated. 



In the Raudal of Canucari the dyke is formed of piled-up 

 granitic boulders. We crept into the interior of a cavern, 

 whose humid walls -were covered with confervee and phos- 

 phorescent Byssus. The river rushed over our heads with a 

 terrible and stunning noise. By accident we had an oppor- 

 tunity of contemplating this grand scene longer than we 

 desired. The Indian boatmen had left us in the middle 

 of the cataract, to take the canoe round a small island, 

 at the other extremity of which, after a considerable cir- 

 cuit, we were to re-embark. For an hour and a half we 

 remained exposed to a fearful thunder-storm. Night was 

 approaching, and we in vain sought shelter in the fissures 

 of the rocks. The little apes which we had carried with 

 us for months in wicker cages, attracted by their plain- 

 tive cries large crocodiles, whose size and leaden-grey colour 

 indicated their great age. I should not have alluded to the 

 appearance of these animals in the Orinoco, where they are 

 of such common occurrence, were it not that the natives had 

 assured us that no crocodiles had ever been seen among 

 the cataracts ; indeed, on the strength of that assertion, we 



