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is remarkable, that we find the schistose jasper 

 which in Europe characterizes the transition 

 rocks % in a limestone that has a great analogy 

 with that of Jura. In the study of forma- 

 tions, which is the great end of geognosy, the 

 knowledge acquired in the two worlds should 

 furnish reciprocal aid to each other. It appears, 

 that these black strata are found also in the 

 calcareous mountains of the Island of Boracha <f. 

 Another jasper, that which is known by the 

 name of the Egyptian pebble, was found by Mr. 

 Bonpland near the Indian village of Curaca- 

 tichej, fifteen leagues south of the Morro of 

 Barcelona, when, returning from the Oroonoko, 

 we crossed the Llanos, and approached the 

 mountains on the coast. This stone presented 

 yellowish concentric lines and bands, on a 

 reddish brown ground. It appeared to me, that 

 the round pieces of Egyptian jasper belonged 

 also to the Barcelona limestone. Yet, accord- 

 ing to Mr. Cordier, the fine pebbles of Suez 

 are owing to a breccia formation, or siliceous 

 agglomerate. 



jasper is found in kidney-stones and in layers both in the 

 Alpine and Jura limestone, especially in the former. 



* The transition limestone and schistus. 



i We saw some of it as ballast, in a fishing boat at Pun- 

 ta Araya. It's fragments might have been mistaken for 

 basaltes. 



X Or Curacaguitiche. 



