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We are surprised to see an Atlantic nation sub- 

 stituting, like the Americans, vitrified lava for 

 iron. In both countries, this variety of lava 

 was employed as an object of ornament : the in- 

 habitants of Quito made beautiful looking glasses 

 with an obsidian divided into parallel laminae. 



There are three varieties of obsidian at the 

 Peak. Some form enormous blocks, several 

 toises long, and often of a spheroidal figure. 

 We might suppose, that they had been thrown 

 out in a softened state, and had undergone a 

 rotary motion. They contain a quantity of vi- 

 treous feldspar, of a snow white color, and the 

 most brilliant pearly lustre. These obsidians 

 are nevertheless but little transparent on the 

 edges, almost opake, of a brownish black, and 

 of an imperfect conchoidal fracture. They pass 

 into pitchstone ; and we may consider them as 

 porphyries with a basis of obsidian. The second 

 variety is found in fragments much less consi- 

 derable. It is in general of a greenish black, 

 sometimes of murky gray, very seldom of a per- 

 fect black, like the obsidian of Hecla and Mexico. 

 It's fracture is perfectly conchoidal, and it is ex- 

 tremely transparent on the edges. I have found 

 in it neither hornblende nor pyroxene, but some 

 small white points, which seem to be feldspar. 

 All the obsidians of the Peak are free from those 

 gray masses of pearl or lavender blue, striped, 

 and in separate pieces of the form of wedges, 



