VOL. LXXXV.] PHILOSOPHICAL TRANSACTIONS. 4Q7 



pale flame, and very different from the deep red of the lava; this was occasioned 

 by the burning of the trees that supported the vines. Soon after the beginning 

 of this eruption, ashes fell thick at the foot of the mountain, all the way from 

 Portici to the Torre del Greco; and though there were not at that time any clouds 

 in the air, except those of smoke from the mountain, the ashes were wet, and 

 accompanied with large drops of water, which I was well assured were to the 

 taste very salt; the road, which is paved, was as wet as if there had been a heavy 

 shower of rain. Those ashes were black and coarse, like the sand of the sea 

 shore, whereas those that fell there, and at Naples some da) s after, were of a 

 light grey colour, and as fine as Spanish snufF, or powdered bark, and contained 

 many saline particles; supposed by Emanuel Scotti, doctor of physic and pro- 

 fessor of philosophy in the university of Naples, to be produced by the mixture 

 of the inflammable and dephlogisticated air, according to experiments made by 

 Priestley and Lavoisier. 



The lava ran but slowly at Torre del Greco after it had reached the sea ; and 

 on the 17th of June in the morning, when I went in my boat to visit that un- 

 fortunate town, its course was stopped, excepting tliat at times a little rivulet 

 of liquid fire issued from under the smoking scoriae into the sea, and caused a 

 hissing noise, and a white vapour smoke; at other times, a quantity of large 

 scoriae were pushed off" the surface of the body of the lava into the sea, discover- 

 ing that it was red-hot under that surface; and even to this day the centre of 

 the thickest part of the lava that covers the town retains its red-heat. The 

 breadth of the lava that ran into the sea, and has formed a new promontory there, 

 after having destroyed the greatest part of the town of Torre del Greco, is 1204 

 English feet. Its height above the sea is 12 feet, and as many feet under water; 

 so that its whole height is 24 feet; it extends into the sea 626 feet. I observed 

 that the sea-water was boiling as in a cauldron, where it washed the foot of this 

 new formed promontory ; and though I was at least an hundred yards from it, 

 observing that the sea smoked near my boat, I put my hand into the water, 

 which was literally scalded; and by this time my boatmen observed that 

 the pitch from the bottom of the boat was melting fast, and floating on the 

 surface of the sea, and that the boat began to leak; we therefore retired hastily 

 from this spot, and landed at some distance from the hot lava. The town of 

 Torre del Greco contained about 18000 inhabitants, all of which (except about 

 15, who from either age or infirmity could not be moved, and were over- 

 whelmed by the lava in their houses) escaped either to Castel-a-mare, which 

 was the ancient Stabiae, or to Naples ; but the rapid progress of the lava was 

 such, after it had altered its course from Resina, which town it first threatened, 

 and had joined a fresh lava that issued from one of the new mouths in a vine- 

 yard, about a mile from the town, that it ran like a torrent over the town of 

 VOL. XVII. . 3 S 



