VOL. LIX.] PHILOSOPHICAL TKANSACTIONS. 503 



ning, which lasted almost the whole time of the eruption, on the mountain 

 only. Besides the lightning, which perfectly resembled the common forked 

 lightning, there were many meteors, like what are vulgarly called falling stars. 

 A peasant, in his neighbourhood, lost 8 hogs by the ashes falling into the trough 

 with their food : they became giddy, and died in a few hours. The last day of 

 the eruption, the ashes, which fell abundantly on the mountain, were as white 

 almost as snow; and the old people here say that is a sure symptom of the erup- 

 tion being at an end. Sir William had been this summer in the island of Ischia ; 

 it is about 18 miles round, and its whole basis is lava. The great mountain in 

 it, nearly as high as Vesuvius, formerly called Epomeus, and now San Nicolo, he 

 is convinced was thrown up by degrees ; and that the island itself rose out of the 

 sea, in the same manner as some of the Azores. He is of the same opinion with 

 respect to mount Vesuvius, and all the high grounds near Naples; having not 

 yet seen, in any one place, what can be called virgin earth. He saw a well 

 sunk a few days ago near his villa, at the foot of Vesuvius, and close by the sea- 

 side. At 25 feet below the level of the sea they came to a stratum of lava, and 

 God knows how much deeper they might have still found other lavas. The soil 

 all round the mountain, which is so fertile, consists of stratas of lavas, ashes, 

 pumice, and now and then a thin stratum of good earth, which good earth is 

 produced by the surface mouldering, and the rotting of the roots of plants, vines, 

 &c. This is plainly to be seen at Pompeii, where they are now digging into the 

 ruins of that ancient city ; the houses are covered, about 10 or 15 feet, with 

 pumice and fragments of lava, some of which weigh 3 lb. (which last circum- 

 stance he mentions to show, that in a great eruption, Vesuvius has thrown stones 

 of this weight 6 miles, which is its distance from Pompeii, in a direct line) ; upon 

 this stratum of jjumice, or rapilli, is a stratum of excellent mould, about 2 feet 

 thick, on which grow large trees, and excellent grapes. We have then the 

 Solfaterra, which was certainly a volcano, and has ceased emptying, for want of 

 metallic particles, and over-abounding with sulphur. You may trace its lavas 

 into the sea. We have the Lago d'Avemo and the Lago d'Agnano, both of 

 which were formerly volcanos; and Astroni, which still retains its form more 

 than any of these. Its crater is walled round, and his Sicilian Majesty takes the 

 diversion of boar-hunting in this volcano; and neither his Majesty, nor any one 

 of his court, ever dreamed of its former state. We have then that curious 

 mountain, called Montagno Nuovo, near Puzzole, which rose, in one night, 

 out of the Lucrine Lake ; it is about 1 50 feet high and 3 miles round. He does 

 not think it more extraordinary that mount Vesuvius, in many ages, should rise 

 above 2000 feet; when this mountain, as is well attested, rose in one night, 

 no longer ago than the year 1538. It is composed of stratas, like mount Ve- 

 suvius, but without lavas. On the whole, if Sir W. was to establish a system, 



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