647 



of the Silla of Caraccas, by the red sandstone 

 of Barquisimeto and Tocuyo, the slaty moun- 

 tains of the Sierra Nevada de Merida, and the 

 eastern Cordillera of Cundinamarca, toPopayan 

 and Pasto, taking" the rumb of the west and 

 south-west, we find in the vicinity of those 

 towns the first volcanic mouths of the Andes, 

 still burning, those which are the most northerly 

 of all South America; it maybe added, that 

 those craters are found where the Cordilleras 

 begin to furnish trachytes at a distance of 18 

 or 25 leagues from the actual coast of the Pa- 

 cific Ocean*. Permanent communications, or 

 at least such as are frequently renewed, be- 

 tween the atmosphere and the interior of the 

 globe, have 'only been preserved along that im- 

 mense crevice on which the Cordilleras have 

 been heaped up § but the subterranean volcanic 

 forces do not display less activity in eastern 

 America, in shaking the soil of the Cordillera 

 of the shore of Venezuela, and of the groupe of 

 Parime In describing the phenomena which 



* I believe the first hypotheses on the relation between 

 the burning of volcanoes, and the proximity of the sea, are 

 found in a very eloquent work, little known, of Cardinal 

 Bembo : JEtna dialogus (See Opera omnia Petr, Bembi, Vol. 

 iii, p. 60) ; and in Vicenti Aliarii Crucii Vesuvius ardensj 

 1632, p, 164 and 235). 



f See the classical work of M. de HoiT, on the spheres of 

 oscillations, and the limits of earthquakes, bearing the title : 



