[ ^56 ] 



may very well reach the ore, and yet carry back only a very 

 uncertain intelligence. The flerile layers of the mountain 

 contain fcattered fubftances exadlly like thofe that in the veins 

 may be taken as a gage to the ore, and in the moft metallic 

 veins one meets with fome firings of Hate, or of other rocks, 

 abfolutely of the fame nature with the mountain : it is evident 

 that the probe, in carrying back with it both the one and the 

 other of thofe matters, cannot give compleat fatisfaclion. 



/I 



'''I 



