( 402 ) 



air, it is introduced with it into the volcanic 

 produds. I cannot, however, deny but 

 that it muft appear furprifing that this fait 

 in conjundion with water fhould have 

 been able to find an entrance into the two 

 glafles of Lipari ; and efpecially the black 

 fpecies, as it is extremely compadt, and has 

 not the leaft appearance of any cleft or 

 crack. But we know that water can fub- 

 tilize itfelf in fuch a manner as to penetrate 

 other bodies equally folid and cpmpadi, ia 

 which our eyes, though aflifted by a lens of 

 a ftrong magnifying power, cannot difcover 

 the fmalleft fiflure or minuteft pore. 



END OF THE THIRD TOLUME. 



