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aflumed a fmooth and vitreous furface. 

 Their internal grain acquired an afpedt 

 rather vitreous than filiceous, even in thofe 

 ftones, which, having for their bafe the 

 horn-ftone, had an earthy appearance. 

 The pieces, except that they adhered by 

 fome points, preferved their former figure 

 an4 angles ; which prefervation of the li« 

 gure takes place in other cafes that I fhall 

 proceed to mention. 



The feltfpar of Mount St. Gothard, or 

 the adularia of Father Pini, loft its change- 

 able colour and tranfparency, became white 

 within, femi-enamellar, and vitreous exter- 

 nally. 



In the feltfpars of Ifchia, the vitrifi- 

 cation penetrated to the depth of fome 



lines. 



In fome of the potteries of Pavia, they 

 ufe a kind of earth, which, from the place 

 where it is digged, is called blella^ which 

 ftrongly refills the fire. It is commonly 



found 



