1INES OP MOUNTAIN EIDGES. 287 



declivity of the Cordilleras of the Andes. The rising of this 

 ridge is so inconsiderable compared to the whole continent, 

 that its breadth in the parallel of Cape Saint Eoche is 

 1400 times greater than the average height of the Andes. 



We distinguish in the mountainous part oi South America, 

 a chain and three groups of mountains, namely, the Cor- 

 dillera of the Andes, which the geologist may trace without 

 interruption, from Cape Pilares, in the western part of the 

 Straits of Magellan, to the promontory of Paria, opposite 

 the island of Trinidad; the insulated group of the Sierra 

 Neyada de Santa Marta ; the group of the mountains of the 

 Orinoco, or of La Parime ; and that of the mountains of 

 Brazil. The Sierra de Santa Marta being nearly in the 

 meridian of the Cordilleras of Peru and New Grenada, the 

 snowy summits descried by navigators in passing the mouth 

 of the Eio Magdalena, are commonly mistaken for the 

 northern extremity of the Andes. I shall soon prove that 

 the colossal group of the Sierra de Santa Marta is almost 

 entirely separate from the mountains of Ocafia and Pam- 

 plona, which belong to the eastern Cordillera of New 

 Grenada. The hot plains through which runs the Bio 

 Cesar, and which extend towards the valley of Upar, separate 

 the Sierra Nevada from the Paramo de Cacota, south of 

 Pamplona. The ridge which divides the waters between the 

 gulf of Maracaibo and the Eio Magdalena, is in the plain 

 on the east of the Laguna Zapatoza. If, on the one hand, 

 the Sierra de Santa Marta has been erroneously considered 

 (on account of its eternal snow, and its longitude) to be a 

 continuation of the Cordillera of the Andes, on the other 

 hand, the connexion of that same Cordillera with the coast 

 mountains of the provinces of Cumana and Caracas, has 

 not been recognized. The littoral chain of Venezuela, of 

 which the different ranges form the Montana de Paria, the 

 isthmus of Araya, the Silla of Caracas, and the gneiss- 

 granite mountains north and south of the lake of Valencia, 

 is joined between Porto Cabello, San Felipe, and Tocuyo, to 

 the Paramos de las Eosas and Niquitao, which form the 

 north-east extremity of the Sierra de Merida, and the eastern 

 Cordillera of the Andes of New Grenada. It is sufficient 

 here to mention this connexion, so important in a geological 

 point of viewj for the denominations of Andes and Cor- 



