[ 41 ] 
lightening which is diftinguifhed here by the name 
of Ferilli. Bracini, in his account of the great one 
of Vefuvius in 163 1, fays, that the column of fmoke, 
which iffued from its crater, went over near an hun- 
dred miles of country, and that feveral men and 
beads were (truck dead by lightening, ilTuing from 
this fmoke in its courfe. 
The nature of the noxious vapours, called here 
mofete, that are ufually fet in motion by an eruption 
of the volcano, and are then manifed in the wells and 
fubterraneous parts of its neighbourhood, feem like- 
wife to be little underdood. From fome experiments 
very lately made, by the ingenious Dr. Nuth, on the 
mofete of the Grotto del Cane, it appears that all its 
known qualities and effedls correfpond with thofe 
attributed to fixed air. Jud before the eruption of 
1767, a vapour of this kind broke into the king’s 
chapel at Portici, by which a fervant, opening 
the door of it, was (truck down. About the fame 
time, as his Sicilian majedy was (hooting in a paddock 
near the palace, a dog dropped down, as was fup- 
pofed, in a fit i a boy going to take him up dropped 
likewife j a perfon prefent, fufpedting the accident to 
have proceeded from a mofete^ immediately dragged 
them both from the fpot where they lay, in doing 
which, he was himfelf fenlible of the vapour j the 
boy and the dog foon recovered. His Sicilian majedy 
did me the honour of informing me himfelf of this 
accident foon after it had happened. I have met 
with thefe mofetes often, when I have been making 
my obfervations on the borders of mount Vefuvius, 
VoL. LXI. G parti” 
