THE 



AMERICAN 

 JOURNAL OF SCIENCE, &c. 



Art. I. — Geological and Miscellaneous Notice of the Province 

 of Tarapaca ; by John H. Blake — with a map. 



Tabapaca, the southernmost province in Peru, is situated be- 

 tween latitude 19° and 21° 30' S. ; the Andes on the east, which 

 separate it from Bolivia, and the Pacific Ocean on the west. 



This province possesses many points of interest to the natural- 

 ist, and affords perhaps as interesting a field for research as any 

 other portion of the continent of South America of the same 

 extent. It forms a part of the great desert of Atacama • but 

 though entirely destitute of vegetation, excepting in a few spots 

 which are irrigated by water derived from the melting snow of 

 the Cordilleras, it is much Jess desolate and lifeless, in its general 

 aspect, than that portion to the south, which forms the western 

 part of Bolivia and the northern part of Chili, where the oases 

 are more widely separated, and throughout a large tract of coun- 

 try no living thing is to be found. 



Two ranges of mountains and a plain, nearly level, extend 

 north and south throughout the province ; and between the An- 

 des and the eastern chain of mountains lies an extensive plain 

 inclined to the west. The surface of this latter plain is broken 

 by numerous streams from the Cordilleras ; it is formed of debris 

 from the Andes, and is covered by huge angular masses of feld- 

 spar and trachyte, and numerous fragments of pumice and grains 

 of sulphur. Among the neighboring mountains are seven or 

 eight volcanoes, some of which occasionally emit a small volume 



Vol. xliv, No. 1.— Oct.-Dec. 1842. 1 



