365 



The view from the height of the Mono is riot- 

 without beauty. The rocky island of Boracha 

 lies on the east, the lofty promontory of Unare 

 on the west, and below is the mouth of the river 

 Neveri, and the arid shores, on which the cro- 

 codiles come to sleep in the sun. Notwithstand- 

 ing the extreme heat of the air, for the ther- 

 mometer, exposed to the reflection of the white 

 calcareous rock, rose to 38°, we walked all over 

 the hill. A fortunate chance led us to observe 

 a very curious geological phenomenon, which 

 we again found in the Cordilleras of Mexico*. 

 The limestone of Barcelona has a dull, even, or 

 conchoidal fracture, with very flat cavities. It 

 is divided into very thin strata, and displays 

 less analogy with the limestone of Cumanacoa, 

 than with that of Caripe, forming the cavern 

 of Guacharo. It is traversed by banks of schis- 

 tose jasper black, with a conchoidal frac- 

 ture, breaking into fragments of a parallelopi- 

 pedal figure. This fossile does not exhibit those 

 little streaks of quartz, so common in the Ly- 

 dian stone. It is found decomposed at it's sur- 

 face into a yellowish gray crust, and does not 

 act upon the magnet. It's edges, a little trans- 

 lucid, make it resemble the hornstein, which 

 is so common in secondary limestones %. It 



* Essai Politique sur la nouvelle Espagne, Tom. ii, p. 535. 

 t Kieselschiefer of Werner. 



{" In Switzerland, the hornstein passing into common 



