( 3*4 ) 
Night time would, in all probability, have appeared, as 
if it were all on Fire. 
Juguft the 7th, the Noife alter’d 3 and from being 
dull, as before, it became very loud, and refembled the 
Noife which is made when feveral great Stones are 
thrown all together into a very deep Well : And I 
really believe that this Great Noife was occafioned by 
feveral large pieces of Rocks, which after having been 
raifed up with the Ifland by the violence of the Fire, 
broke of by reafon of their weight, and fell back again 
into*the Subterranean Caverns. What confirms me in 
this thought is, that I faw then the Ends of this Ifland 
in fo great a Motion, that after having appear’d for fome 
Days, they then difappear’d, and afterwards re-appear’d 
again a-new. Howfoever it was, this Noife after having 
continued fo for near a Month, was followed by another 
much louder and more extraordinary : ft fo nearly re- 
fembied Thunder, that when it did really Thunder, as 
it happen’d to do 3 or 4 times, there was very little dif- 
ference between the one and the other. 
As the Paffage, which the Fire had made itfelf by its 
violence thro’ Co many Rocks, was not, in all probabi- 
lity, in a ftrait Line, and was in fome places narrower, 
and in others larger and more free 3 fo it is probable, 
that the Fire, or rather the Sulphureous and burning 
Exhalations, caufed this great Noife, by turning from 
fide to fide in thefe winding Caverns, and endeavouring 
to get a Paffage out, which was difficult for them to 
find : Which was the caufe that the Noife of this Sub- 
terraneous Thunder was foinetimes not fo loud, and a 
little while after grew more violent, and fometimes was fo 
ftunning, that People talking together could fcarce hear 
one another fpeak 3 and that the Black Ifland, which 
was already very high, feemed to crack on every fide 3 
and in (hort, that the inclofed Fire, after feveral Wind- 
ings and Turnings, having colle&ing a fufficient force, 
was 
