ITALY. LETTER XI. 135 



fwallowed afterwards. According to thefe facts 

 and fuppofuions, Vefuvius, after having burnt 

 out, may fink to the ground, leave but a part of 

 its circumference {landing, and in its place a 

 pool like Lago d'Agnano, d'Averno, and others in 

 Italy. 



They fuppofe, that there is a fubterranean con- 

 nection between V(fu r oius^ the Solfatara^ jEtna, 

 Strombolo *, and the Ocean. I do not know this.; 

 but there is good rcafon to fuppofe, under ground, 

 large holes and excavations. Amazing quantities 

 of combuftible and vitrefcent materials have been 

 fince fo many centuries confumed and thrown out ; 

 and the vomiting of large {tones fuppofes ftrong 

 currents of air in thefe long and fpacious caverns. 

 Certain it is, that Vefyvius has, in former times, 

 vomited large quantities of water ; and that the 

 fea, during the eruptions and earthquakes, is in a 

 ftrong commotion. They tell us that lea fhells 

 have appeared together with this water. 



The probable and poffible caufes of the fub- 



* Strcmboli is one of the Liparean iflands, in the Mediter- 

 ranean, near Calabria; containing a mountain which is' ever 

 burning, and on all fides furrounded by fea. Some Italian 

 Philofophers are of opinion, that mod part of vclcanos have 

 been, in former times, covered by fea, and raifed above its 

 level by their eruptions. By this fuppofition, they very eafily 

 explain the mixture of volcanic and marine productions in. 

 jhc Vicentine diitrift. 



K terraneous 



