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hemisphere to another, the inhabitant of the 

 north lands on some distant shore, he is sur- 

 prised to find, amid a crowd of unknown pro- 

 ductions, those strata of slate, micaceous schist, 

 and trappean porphyry, that form the arid coasts 

 of the Old Continent bathed by the icy ocean. 

 Under every climate the rocky crust of the 

 Globe presents the same appearance to the tra- 

 veller ; he every where finds, and not without 

 emotion, in the midst of a New World, the rocks 

 of his native country.. 



This analogy in unorganized nature extends 

 even to those little phenomena, which we should 

 be tempted to attribute to causes merely local. 

 In the Cordilleras, as well as in the mountains 

 of Europe, granite sometimes offers aggregations 

 in the form of spheroids flattened and divided 

 into concentric layers : under the tropics as 

 well as in the temperate zone, we find in the 

 granite some of those masses abounding in mica 

 and hornblende, which resemble blackish balls 

 enclosed in a mixture of feldspar and milky 

 quartz ; schillerspar is found in the serpentines of 

 the isle of Cuba, as well as in those of Germany ; 

 the mandelstein and perlstein of the elevated 

 plain of Mexico appear identic with those seen 

 at the foot of the Carpathian mountains. The 

 superposition of the secondary rocks follows the 

 same laws in regions the most remote from each 



