68 PATAGONIA. [1839 



outline, in regard to it. The Andes here consist of but one 

 cordillera, the mean height of which is estimated at three 

 thousand feet, although there are many peaks opposite the 

 Archipelago of Chiloe, from five to six thousand feet high. 

 This mountain range divides the country into two unequal 

 parts ; the larger of them, by far, lying on the East. The 

 western coast is extremely abrupt and precipitous, and is 

 skirted with numerous irregularly shaped and rocky islands. 

 On the East, the surface of the country rises from the At- 

 lantic to the Andes, in a succession of terraces, all of which 

 are arid and sterile ; the upper soil being chiefly composed of 

 marine gravelly deposits. On the banks of the rivers, herb- 

 age and trees are occasionally found, but with this exception, 

 these terraces produce nothing but a coarse wiry grass, and 

 a small thorny shrub fit only for fuel. The general sterility 

 of East Patagonia is probably occasioned by the westerly 

 winds that prevail throughout most of the year.; the moisture 

 which they bring with them from the Pacific, is condensed 

 and precipitated in the mountains and their immediate vi- 

 cinity, and they consequently become quite dry. Almost the 

 only moisture, therefore, that is brought to this desert tract, 

 comes with the easterly winds, which are very rare. Near 

 the Andes, however, where the grateful moisture of the wes- 

 terly winds is precipitated, wheat, maize, beans, lentils, 

 pease, and other similar grains and vegetables, are raised. 



The most prevalent mineral formations of East Patagonia, 

 are porphyry, basalt, sandstone, and a friable rock resembling 

 chalk. Organic remains are found of different kinds, and in 

 great numbers. There is an abundance of rodent mammals 

 in the country, but there are few varieties of larger animals. 

 Guanacoes are the most common, and are frequently seen in 

 droves numbering several hundred. The puma, the inveter- 

 ate enemy of the guanaco, and the fox, are the only other 

 wild quadrupeds worthy of mention. The principal birds 

 are the condor, the cassowary, and the rhea, or South Amer- 

 ican ostrich. 



(3.) Until of late years, it was pretty generally supposed 



