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hardly recognized the vestige of a vein of quartz 

 on the slope of a hill. The falling down of the 

 earth caused by the rains had changed the sur- 

 face of the ground, and rendered it impossible to 

 make any observation. Great trees were grow- 

 ing in the same places, where the gold-washers 

 had worked twenty years before. It is proba- 

 ble, that the mica-slate contains here, as near 

 Goldcronach in Franconia, and in the country 

 of Saltzbourg, auriferous veins ; but how is it 

 possible to judge whether this vein be worth the 

 expense of being wrought, or whether the ore 

 occur only in nodules, and in less abundance 

 in proportion as it is so rich ? In order to de- 

 rive some advantage from our fatigues, we 

 made a long herborization in the thick forest, 

 that extends beyond the hato, and abounds in 

 cedrelas, browneas, and fig-trees with nym- 

 phea leaves. The trunks of these last are co- 

 vered with very odoriferous plants of vanilla, 

 which in general flower only in the month of 

 April. We were here dgain struck with those 

 ligneous excrescences, which in the form of 

 ridges, or ribs, augment in so extraordinary a 

 manner, and as far as twenty feet above the 

 ground, the thickness of the trunk of the fig- 

 trees of America. I found trees twenty-two 

 feet and half in diameter near the roots. These 

 ligneous ridges sometimes separate from the 

 trunk at a height of eight feet, and are trans- 



