( 95 ) 



indifFerently, but, with refped: to flones, 

 feems principally to attack the carbonates of 

 lime ; though not all of thefe, as appears 

 from the hard Iftrian marble with which the 

 fuperb palaces and fumptuous edifices of 

 Venice are built, and which remains unin- 

 jured for a long feries of years. I likewife 

 obferve that volcanic ftony fubilances are 

 little, or not at all, injured by the air of the 

 fea; and I am the more confirmed in my 

 opinion that the incavations in the litoral 

 lava of which I am now fpeaking muft be 

 attributed to the a(flion of aeriform gafes, and 

 not to that of the fea air, from obferving the 

 fame, likewife, in the feltfpar, a ftone much 

 lefs liable to this kind of alteration than 

 many others. 



After having made thefe obfervationS) T 

 left the bay, and began to coaft the iHand 

 towards the left, on the northern fide. I 

 had fcarcely proceeded one hundred and 

 ^fty paces when I met with a rock of lava, 

 about thirty feet high, and equally broad, 

 lifing almoft perpendicularly from the water. 



This 



