[ 8 ] 
pared by nature. This, mixed with water, great or 
fmali pumice ftones, fragments of lava, and burnt mat- 
ter, may naturally be fuppof^d to harden into a hone of 
this kind ; and, as water frequently attends eruptions 
of tire, as will be feen in the accounts I fhall give of 
the formation of the new mountain near Puzzole, 
lam convinced the hi ft matter that ilTued from Ve- 
fuvius,and covered Herculaneum, was in the hate of 
liquid mud. A circumftance ftrongly favouring my 
opinion is, that, about two years ago, I faw the head 
of an antique ftatue dug out of this matter within the 
theatre of Herculaneum ; the imprehion of its face 
remains to this day in the and might ferve 
as a mould for a caft in plaifter of Paris, being 
as perfect as any mould I ever faw. As much may 
be inferred from the exa6t refemblance of this matter, 
or tiifa^ which immediately covers Herculaneum, to 
all the tufas of which the high grounds of Naples 
and its neighbourhood are compofedj I detached a 
piece of it fticking to, and incorporated with, the 
painted flucco of the infide of the theatre of Her- 
culaneum, and hiall fend it for your infpedtion 
It is very different, as you will fee, from the vitrified 
matter called lava, by which it has been generally 
thought that Herculaneum was deftroyed. The 
village of Refina and fome villas ftand at prefent 
above this unfortunate town. 
To account for the very great difference of the 
matters that cover Herculaneum and Pompeii, I have 
often thought that in the eruption of 79 the moun- 
^ This piece Is now in the Mufeum of the Royal Society, 
together with many other fpccimens, mentioned in this and in the 
following lewer. M. M. 
2 
tain 
