( 225 ) 



The fccond lava, which is of a light 

 grey colour, might at firft be taken for a 

 cari)onate of lime ; but, when attentively 

 examined in the recent fradures, its bafe 

 is found to be a hard horn-ftone, contain- 

 ing fome black mica, and a few feltfpathofe 

 points. 



The third lava, with fome varieties little 

 differing from it, has, in like manner, its 

 bafe of horn-ftone. Its colour is a pale 

 grey, its pafte earthy, w^ith an argillaceous 

 fmell ; and, befides numerous particles of 

 black mica, it contains thick redangular felt- 

 fpar lamellae. 



The fKoerls, micas, and feltfpars of 

 thefe three lavas, when fufed in the fur- 

 nace, arc, together with the bafe, reduced 

 to an enamellar and cellular fcoria. 



Though the three ftones above defcribed 

 have not the appearance of having ever 

 formed currents, nor the porofity of fome 

 lavas, I do not hefitate to call them by that 



VOL. III. Q^ name; 



