[ 26 3 



III. Sketch of a Geological Delineation of Soidh Ameriin. 

 By F. A. Von Humboldt. 



[Continued from our last volume, p. 357.] 



JL HK Cordillera of Parima ncvcT reaches to the same height 

 as the Sierra Nev^ada in the }5rovince of Caraccas, which is 

 2350 toise?. Their hiorhest siunniit seems to be the Ccrro 

 *}e la Esmeralda, or the mountain Duida, which, bv trigo- 

 nometrical measurement, I found to be 1323 loises above 

 the surface of the feea, which is the height also of the Ca- 

 nigou. This mountain is situated in a delightful plain co- 

 vered with ananas and palms : the monstrous mass which 

 it exhibits towards the Mission and the rivers Canu-canuma 

 and Tanijtama, and the flames it von^its up towards the 

 €nd of the rainy season, give it a romantic and majestic ap- 

 pearance. No Indian is able to clamber up to the top of 

 this mountain and the rocks of its summit without a week's 

 Jabour, because the luxuriance of veQ;etation in this climate 

 impedes the progress of travelling. Next to the Duida, the 

 Maraguaca, more towards the east of the river Simirimoni, 

 and the high cordillera of Cunarami and Calilamini, which 

 at Maypure and St. Barbara is known under the false name 

 inf Sipapo, are the highest summits of the chain; thev arc 

 from 1000 to 1100 toises in height. The con?mon height 

 of the cordillera, however, does not exceed 600 toises, and 

 sometimes it is less, as the part situated between the left 

 bank of the Cassiguiarii, an arm of the Orinoco which 

 .connects together the Kio Negro and the river Amazon, 

 and the sources of the cataracts and Piramena between Ca- 

 richana and Morocote, is dest,roved, and still exhibits insu- 

 lated rocks rising from the ground. "J"he cause of this de- 

 struction seems to have beeii an eruption of water from the 

 ■bason oi the Amazon river towards the bason of Calabozo 

 and Baxo-orinoco, which differ in height about 160 toises. 

 The geologijcal chart of this district which I have con- 

 FtructecT represents an immense valley which unites the 

 Llanos of the iiio Negro, Cas^;iguiare, and Amazon, with 

 those of the province of Caraecas, Barcelona, and Cumana ; 

 a valley which sinks down towards the north, and is inter- 

 sected by a large series of single rocks which show the di- 

 rection of the wld cordillera on the Iwnks of the Guaviare 

 and Nula in the province of Casscmora. The eastern ex- 

 tremity of this "alley is the lowest part of it, and therefore 

 the remains of the water of the Orinoco cut out for itself a 



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