lói A VOYAGE TO Book VII. 



h jilt to account for the formation of these masses of 

 siiver, in a barren and moveable sand, remote from 

 any ore or mine. Two conjectures may, however, 

 be oftered. The first by admitting the contiuiiai 

 reproduction of metals, of which there are iacieed 

 here so many evident proofs ; as the matrices of gold 

 and silver, met with in many parts of this kingdom. 

 Nay the very mines themselves^ after being long for- 

 saken, have again been worked with great advantage ; 

 but the skeletons of Indians found in old mines, and 

 covered with fibres of silver, and the inward parts 

 also full of the same metal, seem to put the matter 

 beyond dispute. If this be admitted, it is natural to 

 conclude, that the primordial mailer of silver is first 

 fluid, and when it has acquired a certain degree of 

 perfection, some parts of it are filtrated through the 

 pores of the sand, still stopping in a place proper 

 for completing the fixation, they there form a solid 

 congeries of silver ; and being joined with those 

 earthy particles they collected in their course to the 

 place wh^re they were absorbed by the pores of the 

 sand, consolidated with the silver. 



Though this conjecture be notdestitute of probabi- 

 lity, yet I am more inclined to embrace the second, as 

 it is, in my opinion, more simple and natural. Sub- 

 terraneous fires» being very common in these parts of 

 America, iis 1 have already observed in speaking of 

 the earthquakes, their activity is doubtless so strong 

 as to melt any metals deposited near the places where 

 they begin ; and to communicate to them a heat 

 sufficient for keeping them a long time in a state of 

 fusion ; and hence a portion of silver thus melted ne- 

 cessarily spreads, and introduces itself through the 

 linger pores of the earth, and continues to expand it- 

 sclt^ till being beyond the reach of heat, it fixes, and 

 re-assumes its former consistency, together w ith other 

 heterogeneous substances collected in its passage. 

 To this hypothesis, two objections may be offered ; 



one 



