(2167:) 
FourthlyJ^SLving exploded the imperfed: Meteorolofy^delivtr d 
by the Aritients of this Mountain^he difcourfeth of Sabterraoe= 
ousHeat, and deduceth theCaufeof it from fome concrete 
oleagiaoLis and fatty fubftances, as fulphiir, bitumen^ and oylj 
eafiiy reducible into flame 5 examining withalLboth what is the 
origin of fuch fulphureous and bitucoinous matter^ and how 
that comes to take flame : Where he digreffeth to fliew, how 
Canpowder is fee on fire^ after he hath defcribed the ccmpo* 
fition^andconfidcred the fl;apendious force of the fame by its 
percuflion* 
^fifthly^ hedeclareihjhow and why theFirein this Mountain 
was kindled i which he conceiveth to have been moft probably 
done by fucha way^as Qiiick-lime is heated by the aifufion of 
Water 5 whereupon he flieweth,how Earth-quakes^Fiamesjand 
Conflagrations may have enfued. 
Swhly^ he examins the origin and produdion of thfe fliaid 
matter that was vitrified upon its being thrown out of this 
Mountain | and is of opinion (which he aflerts by reafon and 
experiment) that it was not any ignited and melted Sulphur or 
Brimft:one,or both together, nor any metallin bodies that were 
converted into thofevafl: flony and black maffesj which they 
call Scmrra's,bm rather Earth and Sand^together with fome AW 
califat Salts, burn 'd by the fervent heat of the JEtnean iumaces^ 
a^idfo turnMintoavirreous fluor, and afterwards, upon theic 
being cool'd by the Air^into hard fubfl:ances ; Explaining with^ 
alljhow the Afperity and Opacity of thefe fl:ones are confident 
with this fentiment. 
Seventhly ^hc difcourfeth pkufibly of the Extent, Form and 
Scite o( the >/£tnean Furnace^aod havingjUpon the examination 
. of divers circumftances^ found it but Imall and narroWj he la.- 
hours to fhewj how, this notwithflianding/o vaft a quantity of 
macterjas amountSjaccordiog to his eftimate,to about, loo^ ooo^ 
000 cubic paceSgCould be therein melted and thence caft Up< 
Eightly,hQ defcribeth the burning down andialling in of the 
higheft top pf j^tna. 
Ninthly^ he inquireth into the Generation of thofe Sands ^-^ 
bovementionedjand withal! giveth an account^why in the New 
04)ening of Mttrnxh^rt were heard fuch terrible and perpetual 
Thundering noifes^as alfo^by what caufe and force thofe Sands 
wer€- thrown out 3 fliewing withall^that they -.were really ■ eS'^i^^/^ 
mot 
