71 



similar to those of rivers. This phenomenon ap- 

 pears to me imexplainable in any other way but on 

 the principle of a general deluge; though some au- 

 thors have, ridiculously enough, accounted for it, 

 by supposing that the ancient Indians amused them- 

 selves in throwing these stones upon this mass, while 

 it was yet soft and in a state of clay. But besides the 

 irrationality of such a conjecture, the Abbé Morales 

 of Cujo, an intelligent naturalist, who carefully exa- 

 mined these mountains, affirms that the interior of 

 this mass is no less filled with these stones than the 

 exterior, which of itself affords a sufficient proof to 

 the contrary. 



The mine of Uspallata extends along the base of 

 the eastern mountains of the plain of the same 

 name, from the thirty-third degree of latitude, in a 

 direct northerly course ; but the termination of it is 

 unknown, for I have been assured, by persons who 

 have followed it for thirty leagues, that it continues 

 to be equally abundant at that distance, and there are 

 those who assert that it is a ramification of the cele- 

 brated mine of Potosi. 



The principal vein is nine feet in breadth, but it 

 branches out upon both sides into several that are 

 smaller, which extend to the neighbouring mountains, 

 and are said to exceed thirty miles in length. The 

 matrix of the great vein is a various coloured earth, 

 which separates it into five parallel divisions or lay- 

 ers, of different thicknesses. The middle layer is but 

 two inches thick ; the ore, which is called by the 

 miners the guida, is black, but so filled v/lth metallic 



