EARTHQUAKE. 
ing of slightly built edifices, an undulating 
or shaking motion, and a deadened sound ; 
but it by no means follows that the origin 
of such were not to be attributed to fire, 
the vapours caused by which may roll 
through cavities, actually pass from a very 
great distance to a volcanic mountain, or 
escape unperceived through the sea or ob- 
scure vents. 
The electric fluid being known to reside 
in the earth in veiy considerable quantities, 
and always seeking an equilibrium, great 
abundance may sometimes collect through 
various causes in a particular spot, whence 
it will be attracted to another less charged 
with this astonishing fluid ; when the tre- 
mendous conflict between it and the air is 
remembered during a storm in our atmos- 
phere, we must readily admit that it may 
produce a strong concussion in the earth, 
and probably be the origin of the slight 
earthquakes peculiar to some countries. 
Another cause of inconsiderable tremb- 
lings, may perhaps proceed from the ope- 
rations of subterraneous streams,' which 
rushing tlirough caverns, and undermining 
vast bodies of earth and stone, those fail 
and shake the neighbouring parts in propor- 
tion to their bulk and weight. When the 
motion of the sea, during an earthquake, 
had destroyed the support of Port Royal, 
in Jamaica, the town sunk into it, in the 
same manner new cavities occurring through 
the tail of earth, the surface must ne- 
cessarily sink in the same degree, if it is 
within the influence of the cause. 
Frezier is of opinion that earthquakes 
should be ascribed to an effect of tlie wa- 
ters, which appear to moisten the earth, in 
passages similar to the veins of living bo- 
dies. Now the waters may occasion earth- 
quakes after several manners, either by 
dissolving the salt scattered through the 
earth, or by penetrating through porous 
lands, mixed with stones, which they insen- 
sibly loosen ; and the fall or removal there- 
of must cause a stroke or shock, such as is 
felt in earthquakes. Lastly, the water pe- 
netrating some sulphurous bodies must there 
cause a fermentation, and then the heat 
produces foul exhalations, which infect the 
air when they open the earth.” 
This extract from a narrative of the 
dreadful earthquakes at Lima in 1746, is 
illustrated by the experiment of M. Le- 
mery related in the memoirs of the French 
Academy of Sciences for 1700 ; that gen- 
tleman having mixed equal quantities of 
filings of iron and sulphur, and tempered 
them with water into the consistence of 
paste, buried them ; they some time after- 
wards agitated the earth, and finally burst 
into a flame. To confirm this effect of 
fire, however generated in the bowels of 
the earth, we shall quote the following 
paragraph from that accurate modern ob- 
server Spallanzani, w'ho was indebted to 
Professor Bottis for the facts contained in 
it, which relate to the production of seven 
small mountains by the eruption of Vesu- 
vius in 1760. After repeated concussions 
of the earth, which were felt fifteen miles 
round Vesuvius, the sides of the fiery moun- 
tain opened in the territory of the Torre 
del Greco, and fifteen volcanoes appeared, 
eight of which were soon after covered by a 
torrent of lava, which rushed from one. of 
them ; the other seven remaining entire, 
and incessantly ejecting from their mouths 
vast quantities of ignited substances, which 
falling almost perpendicularly around the 
volcanos, produced, in the short space of 
ten days, seven small mountains, of various 
heights, disposed in a right line. During 
these ejections, the noise which accompanied 
them sometimes resembled that of violent 
thunder, and at others the discharge of 
number of cannons. Several of the burn- 
ing stones, even the largest, were thrown to 
the height of 960 feet, and some fell at a 
considerable distance from the mouths 
whence they were thrown. These eructa- 
tions shook all the neighbouring country, 
and the roarings of the mountain were 
dreadful to the inhabitants. 
That there are many substances existing 
■within the depth of the earth, which, coales- 
ced, produce fire, cannot be disputed, but 
that they exist in such amazing quantities 
as to afford fire for centuries, seems at least 
problematical ; there is therefore but two 
ways of accounting for their continuance, 
either that the volatile effluvia of the ig- 
nited matter, collected on the sides of vol- 
canic caverns, becomes new fuel ; or that 
heat being necessary for the various pro- 
perties of the globe, a self-existent fire, co- 
eval with the creation, has been placed 
within it by tire wisdom of the Creator, an 
idea not of more doubtful evidence than 
the existence of the electric fluid invisible, 
or any other of the phenomena of nature 
by which we are surrounded. (See Volca- 
no). Admitting these premises, another 
cause of earthquakes occurs; it is well 
known, that volcanos communicate with 
the sea, by the frequent discharge of saline 
water and tufa, or the slime and mud of its 
