;• [* 3 ] 
tania fide, and many others on the other fide of the- 
mountain, all of a conical form, and each having Its 
crater ; many with timber trees flourifhing both 
within and without their craters. The points of thofe 
mountains, that I imagine to be the moll: ancient, 
are blunted, and the craters of courfe more extenfive 
and lels deep than thofe of the mountains formed by 
explofions of a later date, and which preferve their 
pyramidal form entire. Some have been fo far 
mouldered down by time as to have no other ap- 
pearance of a crater than a fort of dimple or hollow 
on their rounded tops, others with only half or a 
third part of their cone {landing ; the parts that are 
panting having mouldered down, or perhaps been 
detached from them by earthquakes, which are here 
very frequent. All however have been evidently 
raifed by explofion ; and I believe, upon examination, 
many of the whimfical fhapes of mountains in other 
parts of the world would prove to have been oc£a- 
fioned by the fame natural operations. 1 obferved that 
thefe mountains were generally in lines or ridges; they 
have mofily a fradture on one fide, the fame as in the 
little mountains raifed by explofion on the fides of 
Vefuvius, of which, there are eight or nine.. This frac- 
ture is occafioned by the lava’s forcing its way out, 
which operation I have defcribed in my account of the 
lad eruption o 1 Vefuvius. Whenever I fliall meet with 
a mountain, in any part of the world,, whofe form 
is regularly conical, with a hollow crater on its top, 
and one fide broken, I fliall be apt to decide fuch a. 
mountain’s having been formed by an eruption, as 
both on Etna and Vefuvius the mountains formed by 
explofion 
