[ 18* ] 
and exhibited a Flame like thofe of Sir James Low- 
ther> very like in the Smell, tho’ fomewhat different 
in the Colour of the Flame. After I had prefs’d 
Part of the Air out of the Bladder, by drawing 
back the Hand, the Flame was fuck’d into the 
Bladder, and fet on Fire, what inflammable Air re- 
main’d, all at once j which went off like a Gun, with 
a great Explofion. 
What is worthy of Notice in this Experiment is, 
that all the Air which fill’d the Bladders was as it 
were generated de novo out of the Mixture, or elfe 
recover’d from being lock’d up in the Body of the 
Metal in an unelaftic State. 
This Experiment will eafily explain a very 
probable Caufe of Earthquakes, Vulcanos, and 
all fiery Eruptions out of the Earth ; for no- 
thing more is requifite than an Intervention of Iron 
with a vitriolic Acid and Water. Now Iron is gene- 
rally found accompanied with Sulphur : And com- 
mon Sulphur may be analyfed into an inflammable 
Oil, and an acid Liquor like Oil of Vitriol. This 
Acid therefore in the Bowels of the Earth, by be- 
ing diluted with a little Water, furrounds the Iron, 
and works upon it in the fame manner as defcribed 
above y an Effervefcence and inteftine Heat arifes ; 
the Air which comes from the Mixture is rarified, 
and becomes very elaftic, its Impetus , by how 
much the more compreffed by the incumbent 
Weight of Earth, is increafed even to an unlimited 
Degree, and at length, like Gun-powder, will re- 
move all Obstacles, and will exhibit to the Specta- 
tors above Ground the terrible Phenomena of Earth- 
quakes and Eruptions. Thefe inflammable Fumes 
1 fome- 
