Geological Delineation of South America, 353 



micaceous schistous mountains of Maniguares, Chuparipari,^ 

 Distilador, Cerro-Grande, the mountain of St. Joseph and ot' 

 Paria: the remainder I have accurately examined, and found 

 in them the same structure, the same direction, and the same 

 incHnation of the strata. The three hollows, or valleys of 

 Caracas, Aragua, and Monai, are remarkable on this ac- 

 count, that the level of them is above the surface of the 

 sea ; they become lower by gradations, and the highest step 

 is the eastern, which may serve as a proof that they were 

 formed at an earlier period than the Llanos, whose decli- 

 vity proceeds from east to west, like the whole continent 

 of South America. By repeated barometric measurement 

 I found the height of the valleys of Caracas to be 416 

 toises, of Aragua 212 toises, above the surface of the sea ; 

 the Llanos of Monai, the western bason, appears to have 

 an elevation of no more than 80 or 100 toises. The valley 

 of Caracas has once been a lake, which formed for itself 

 an efflux through the Quebrada de Tipe, Catia, and Rio 

 Mamon ; the bason of Aragua appears, on the other hand, 

 to have become dry by gradual evaporation ; for the remains 

 of the old water (loaded with muriate of lime) are still seen 

 in the lake of \'"alencia, which becomes less every year, and 

 discovers islands which are knovin under the name of Apa- 

 recidas. The height of the cordillera of the coast is com- 

 monly from 600 to 800 toises; the highest peaks. Sierra 

 de Nevada de Merida and the Silla de Caracas, (to which 

 we undertook a laborious journey with our instruments) 

 are 2350 and J31G toises in height. To the west they al- 

 ways become lower, and the height of Cape Codera is only 

 l/fi toises. The Macanao, on the island Marg;iretha, 

 w hich I measured trigonometrically, is not more in height 

 than 342 toises ; but this speedv depression takes place only 

 in the primitive niountams of the cordillera. On the 

 eastern coast secondary accumulations of lime rise frOm 

 Cape Unare to a more considerable height than the gncis 

 and micaceous schistus ; these calcareous rocks, which are 

 covered with sandstone of a calcareous base, and which 

 accompany the cordillera of the coast in its southern decli- 

 vity, are very low on the side towards Cura, but rise in a 

 mass towards the eastern extremity of the continent. 



In Bergantin they are 702 toises high, in CoccoUard 392, 

 in Cucurucho du Tuminiquiri (the highest summits of the 

 province of Cumana) 976 toises, and the pyramid ot the 

 Guacharo rises above 820 toises : from Cape Unare they 

 fonn a separate ridge of mountains, in which the original 

 ridge totally disappears ; thev arc connected also with the 



\'oi,. XVII. No. 08. ' Z micaceous 



