( 344 ) 



lities of the fubftanccs I ufed, and the re- 

 fults obtained. 



Thefe fubftances were fix in number : a 

 lava with garnets from Vefuvius -, another, 

 which, vAicn I vifited that volcano, had re- 

 cently flowed ; a lava of Vulcano, invcfted 

 with a criifl of enamel j the lava continu- 

 ally ejedted by Stromboli ; the lava Vv^hich, 

 in 1787, iflued from the higheft crater of 

 Etna ; and a folid pumice of Lipari, I 

 have already defcribed each of thefe pro- 

 du.d:s, when treating of their refpedlive vol- 

 Canos. 



After they had been expofed to the fire 

 eight hours, in matraifes, nothing was found 

 to afcend above the mercury but atmofpherip 

 air, or a portion of tliat the veffels con- 

 tained. Thefe fix produ6:s, therefore, af- 

 forded no indication of any perm.anent 

 gas ; but they evidently fliowed that they 

 had pafTed from the ftate of liquidity to 

 |:hat of a flroncj galification, from the 



quantity 



