52 Notice of Hayden's Geological Essays. 
these cavities communicate in any manner with the oceans, 
and are (as if they exist at all, they probably are,) filled 
with water, there exist, we conceive, agents very competent 
to expel the water of these cavities, and this to deluge, at 
‘Any time, the dry land. These agents are the aerial fluids 
—the gases—whose competency to any and every degree of 
energy, which a given mechanical movement may require, 
is abundantly exhibited, in the rending force of gun powder, 
and of the other still more potent explosive: compositions, 
nd im the phenomena of earthquakes and volcanoes, whose 
mechanic 
sudden and abundant evolution of aeri 
effects, we conceive, depend principally upon 
ial bodies. These 
bodies, suddenly evolved, and su bjected to pressure and re- 
sistance, are competent not merely to propel cannon. balls 
and bombs, to burst rocks and to explode mines—they can 
rend mountams—they can rock them from their bases— 
ke continents, and cause t 
they can s the globe itself to vi- 
rele, : Sens Ge ait sex 
Ma elevate a column of wa- 
ev 
it should transcend the 
5 d be equal to the effort. 
d they be disei tly, in the vast sub- 
terraneous and subaqueous ‘cavities, they would of course 
occupy the roof or vaults of the cavity, and would there- 
fore expel the water, which we suppose they may contain, 
and this water rising and spreading it 
might, by its abundance, more or less 
more o 
My 
water, as ina fire-engine, If it 
pressure would split the ineumben 
fects. It is sufficient to evince that the possi 
that if exerted, they are competent hes d ellen 
os A fea! : Sets 4 ae ar ae ; tty eS gaan) 
aie ly even much greater, according to the deductions of} aske 
era eee 
