81(1 MOUNTAINS OF BRAZIL. 



rise only to the height of 194 toises. The distinctive cha- 

 racteristics of the group of the mountains of Parime are 

 the rocks of granite and gneiss-granite, the total absence of 

 calcareous secondary formations, and the shelves of bare 

 rock (the tsy of the Chinese deserts), which occupy im- 

 mense spaces ill the savannahs. 



V. GROUP OF THE BRAZIL MOUNTAINS. This group 

 has hitherto been marked on the maps in a very erroneous 

 way. The temperate table-lands and real chains of 300 to 

 500 toises high, have been confounded with countries of 

 exceedingly hot temperature, and of which the undulating 

 surface presents only ranges of hills variously grouped. 

 But the observations of scientific travellers have recently 

 thrown great light on the orography of Portuguese 

 America. The mountainous region of Brazil, of which the 

 mean height rises at least to 400 toises, is comprehended 

 within very narrow limits, nearly between 18 and 28 

 south latitude ; it does not appear to extend, between the 

 provinces of Goyaz and Matogrosso, beyond long. 53 west 

 of the meridian of Paris. 



"When we regard in one view the eastern configuration of 

 North and South America, we perceive that the coast of 

 Brazil and Guiana, from Cape Saint Roque to the mouth of 

 the Orinoco (stretching from S.E. to N.AV.), corresponds 

 with that of Labrador, as the coast from Cape Saint Roque 

 to the Bio de la Plata corresponds with that of the United 

 States (stretching from S.W.toN.E.). The chain of the Alleg- 

 hanies is opposite to the latter coast, as the principal Cor- 

 dilleras of Brazil are nearly parallel to the shore of the 

 provinces of Porto Seguro, Bio Janeiro, and Rio Grande. 

 The Alleghanies, generally composed of grauwacke arid 

 transition rocks, are somewhat loftier than the almost 

 primitive mountains (of granite, gneiss, and mica-slate), of 

 the Brazilian group ; they are also of a far more simple 

 structure, their chains lying nearer to each other, and pre- 

 serving, as in the Jura, a more uniform parallelism. 



If, instead of comparing those parts of the new continent 

 situated north and south of the equator, we confine ourselves 

 to South America, we find en the wester a and northern coasts 



