174 



winds ; they rise where the breeze cannot come ; 

 and if the mountains of the Upper Oroonoko, 

 the tops of which are generally crowned with 

 trees, were more elevated, they would produce 

 the same impetuous movements in the atmos- 

 phere, as we observe in the Cordilleras of Peru, 

 of Abyssinia, and of Thibet. The intimate con- 

 nection that exists between the direction of 

 rivers, the height and disposition of the adjacent 

 mountains, the movements of the atmosphere, 

 and the salubrity of the climate, is a subject 

 well worthy attention. The study of the sur- 

 face and the inequalities of the soil would indeed 

 be irksome and steril, were it not connected 

 with more general considerations. 



At the distance of six miles from the island of 

 Piedra Raton we passed first, on the east, the 

 mouth of the Rio Sipapo, called Tipapu* by the 

 Indians ; and then, on the west, the mouth of 

 the Rio Vichada. Near the latter are some 

 rocks covered by the water, that form a small 

 cascade, or raudalito. The Rio Sipapo, which 



* The sources of the Rio Tipapu, it is said, are north of 

 the parallel of Atures, on the eastern side of those granitic 

 mountains, from which the Rio Cataniapo rises. In the 

 upper part of it's course it bears the name of Uapu or Tuapu. 

 One of it's tributary streams, the Aumna, which SurviJle has 

 transformed into Abana, and Caulin into Amanaveni (water or 

 river, veni, of Amana), is remarkable for the fine cascade of 

 Arucuru, above the Raudal of Quiamacuana. 



