TRAVELS IN BRAZIL. 



SI 



wood. Here, as immediately under the line, the 

 wood is of the greatest compactness and without 

 any traces of rings marking the age. 



The geognostic nature of the country in the 

 neighbourhood of the city offers but little variety. 

 The predominant formation is a sand iron-stone, 

 and in which there are often fragments of a white 

 quartz, partly round, partly angular, and which 

 is therefore a kind of breccia. At an inconsi- 

 derable depth this rock rests on the gneiss-like 

 granite, rarely basking out, and with which the 

 streets of the city are partly paved. Between 

 and over it, are several layers of lithomarge of a 

 brick and brownish red, ochre yellow, and lavender 

 blue, just as they are seen here and there along the 

 road from Rio ; for instance at Paranangaba. These 

 fossils belong to a very extended formation, which 

 we again met with in many places in Minas Geraes, 

 and which everywhere contains gold. The metal is 

 disseminated in larger or smaller grains through the 

 mass, particularly of the ferruginous cement. These 

 gold mines were formerly much worked, not only 

 in the immediate vicinity, but particularly in the 

 mountains of Jaragua, two miles to the south of 

 this town. According to Mawe's statement, the 

 poor collect the gold, which after heavy rains is 

 washed out of the pavement of the streets. The 

 smelting house of S. Paulo used to furnish a consi- 

 derable quantity of gold, but this establishment is 

 now broken up, and the little metal found here 



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