( 8i7 ) 
V. A Letter from Mr. Martin Hartop at Naples 
to the Fublijher. Together with an Account of 
the late Earthquake in Sicily. 
Worthy SIR, 
IHave fent you, as you defir'd, all the Account which 
has yet feen the Light of the late Earthquake in Si- 
cily. There was nothing that ever I could hear of par- 
ticular in it, and therefore you can expecSt no great mat- 
ter of Refle&ion upon it. However, to comply with 
your Commands, I (end you my general Thoughts of 
this and fuch like Vhosnomena. 
Firft, It feems highly probable that thefe Tremblings 
of the Earth proceed from the fame incens'd matter, 
which finding a way at other times through the Mongi- 
lello, has fo furioufly broken out in Smoak and Fire 
This appears by the Tragedy of Catania. Now you 
muft know the Eruptions of thefe Mountains are of two 
forts the one not fb very violent as to difturb much the 
adjacent Country, and this happens once in two or three 
Months, and lafts three or four days. The other is more 
furious and of longer Continuance, and is obferv'd here 
at Naples to happen to Mount Vefuvto once in about 
Eighty Years, as I heard the ingenious Mr.Peccacio fay. 
Of thefe, thelaft, which as well as I remember, he faid 
was in 1632. was fo very violent, that by the beft of 
his Obfervation it caft the Rocks three Miles into the Air. 
Now from the burning or not burning of this Hdl, Na- 
ples (and without doubt the fame holds in Sicily') calcu- 
lates its fafety or danger ofJEarthquakes : For without 
doubt the matter is perpetually burning under the Moun- 
tain f and thofe vaft Clouds of Smoak which daily ifTue 
out bt the top, if the Cavity happen by any Rock or 
P p z inward 
