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Firft, fragments of two kinds of lava ; 

 the one black, of a fcaly fradure, and which 

 moved the magnetic needle at tlie diftance 

 of two lines : the other of a grey ground, a 

 very rough furface, an unequal frad:ure, 

 which gave fparks with fteel, and contained 

 fmall plates of feltfpar. Both were of the 

 horn-ftone bafe, and emitted a ftrong argil- 

 laceous odour. 



Secondly, feveral pieces of vitreous lava, 

 of a very beautiful colour, between a green 

 and a blue : by its fmoothnefs, clear frac- 

 ture, its afped:, and want of hardnefs, it re- 

 fembles the pitch-ftone, or pitch-blende. 



Thirdly, numerous fmall pieces of a ci- 

 nereous compact pumice. 



Fourthlyj pieces of a whitillx feml-tranf- 

 parent glafs. 



Fifthly, fmall pieces of a colourlefs glafs, 

 refembling in tranfparency factitious glafs. 

 The largefl piece was fourteen lines in 



length, 



