22 GEOLOGICAL MEMOIRS. 



they were quite dry. The same fire however threw out, at the same 

 time, a light earth and smaller stones, to a much greater height, and 

 these fell down in a soft muddy state; an evident proof that they had 

 reached the higher region, and that the vapours, like other vapours 

 which rise to the same height, were converted into water. This was 

 the cause that the ashes fell in a softened state, mixed with a small 

 quantity of water, although the sky was clear. 



I could now state the natural causes of the drying-up of the sea- 

 bottom, and the mode by which that drying-up, by means of the 

 little stream, first of cold and afterwards of tepid water, was brought 

 about; I could also state the causes of the sinking of the ground and 

 the elevation of it that followed, and finally the causes of the out- 

 burst of the fire, and of the earthquakes which were felt here ten 

 days before, and so frequent as ten in an hour, which unceasingly 

 shook the earth in Pozzolo, but entirely ceased both here and there 

 as soon as the eruption took place. But as I know that Messer Si- 

 mone Porzio, who possesses a thorough knowledge of the subject, has 

 written to the Viceroy and to the highly distinguished Farnese, I 

 will not seem to be decking myself with the merits of others. Poz- 

 zolo is quite deserted by the inhabitants, and you would not know 

 the place of the sea here, for it would appear like a ploughed field, 

 and it has a covering of what is here called rapillo about half a palm 

 thick (1^ inch), which is so light as to swim on water. But what 

 is to me inconceivable is the mass of stones and ashes that was poured 

 forth from this gulf; and when we take into account the quantity 

 that must have fallen into the sea, and upon the newly-formed hill, and 

 think of the ashes which, as you know, were scattered in all direc- 

 tions, and are the remains of burnt materials, and if we imagine all 

 these brought together in one place, what an immense mountain they 

 would form ! I spoke this morning with a man from Eboli, a town 

 forty-five miles distant from the fire. He told me that the ashes had 

 fallen in that place, that the fire had extended ten miles under ground, 

 and that this was the cause of the extraordinary quantity of earth 

 that had been thrown into the air. Had this eruption not hap- 

 pened, the fire must have extended much further under ground ; and 

 God grant that the vault may not spread out under Naples ! Only 

 yesterday, as we returned to Pozzolo by land, we saw two fire-gulfs, 

 just opened in the ground three miles from Naples. Many opinions 

 have been expressed by very able men, and some think that Naples 

 is in great danger. There have been some processions, and innu- 

 merable very deep wells have been sunk between Naples and Poz- 

 zolo, " as it were to bleed the fire." Viewed as an omen, the event 

 is thought to forebode, as the rockets were driven from west to east, 

 that the emperor is going to attack the Turks. 



Leonard Horner. 



