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particles which seem to have been subjected to 

 particular attractions. I could not follow the 

 line of junction of the gneiss and granitic forma- 

 tions. According to angles taken in the valleys 

 of Aragua, the gneiss appears to descend below 

 the granite, which must consequently be of a 

 more recent formation. We shall examine else- 

 where the relative antiquity of this rock, when, 

 after our return from the Oroonoko, we shall 

 attempt to trace in a particular chapter the 

 geological table of formations, from the equator 

 to the coast of the Caribbean sea. The appear- 

 ance of a stratified granite excited my attention 

 the more, because, having had the direction of 

 the mines of Fichtelberg in Franconia for several 

 years, I was accustomed to see granites divided 

 into ledges of three or four feet thick, but little 

 inclined, and forming masses like towers, or old 

 ruins, at the summit of the highest mountains # . 

 The heat became stifling as we approached 



* At Ochsenkopf, at Rudolphstein, at Epprechtstein, at 

 Luxbourg, and at Schneeberg. The dip of the strata of 

 these granites of Fichtelberg is generally only from 6° to 10°; 

 rarely (at Schneeberg) 18°. According to the dips I ob- 

 served in the neighbouring strata of gneiss and mica slate, I 

 should think, that the granite of Fichtelberg was very ancient, 

 and serving as a basis for other formations ; but the strata of 

 gruenstein, and the disseminated tin-ore, which it contains, 

 may lead us to doubt, from the analogy of the granites of 

 Saxony containing tin, it's great antiquity. 



