The citizen-Republican. (Scotland, Bon Homme County, S.D.) 1???-19??, 1906-05-10
THEORIES and CAUSES
OF EARTHQUAKES
May Be Act Of God or Again
May Be the Attraction
Of Planets.
MOST PLAUSIBLE THEORY
'olcanic Eruptions and Fires in ths
Earth's Center Probably the Prin-
cipa! Cause of Earthquakes Like
the One in Frisco.

the One in Frisco.
An earthquake is a trembling Of the
earth's crust due to internal causes. 1t
consists Of a series of undulatory i'm
pulses or elastic waves, transmitted
through the rocks of the crust in some
Wha the same way that sound is trans
mitted through the air. An earthquake
tremor may be felt on the surface dis
tinctly and not in the lower levels Of
a deep mine and vice versa. The size
of the area where the trembling is per.
ceptible probably bears some proportion
to the violence of the initial shock. The
great Lisbon earthquake of 1915 was
distinctly felt from Madeira to Great
Britain, or over the whole of southwest
Europe and northwest Africa. The
Charleston earthquake was felt from
northern Florida to New England, and
as far west as Iowa, or over an area
approximately 100 miles long and 500
miles wide. In the Lisbon earthquake
the tremors lasted about six
When an earthquake occurs beneath
the sea the ocean above spreads out
wardly in low, long waves that travel
rapidly, but are slower than the earth
waves. An earthquake in the North
Pacific in June, 1896, caused a wave
forty feet high along the northern
coast or Japan that did great damage,
over $1,000 persons being drowned.
In the United States earthquakes are
comlnenest in California, and in gem
eral earthquakes are more often felt
near the coast than inland. Earth
quakes are usually conmonest in re.
gions Of present or recent volcanic ac-
tivity. Earthquakes often frequently
proceed volcanic outbursts and cease as
the eruptions begin.
Some Theories on Earthquakes.
Briefly stated the theories on the
causes of earthquakes follow:
l. The theological theory held by an
unusual number of persons, who believe
that the earthquake IS due to the d.
rect intervention OF God as punishment
for sin or a warning to righteousness,
The theory is Of the greatest antiquity.
2. The mechanical theory which i'm
putes the earthquake to the slipping of
rock strata and lays especial stress
upon the earth's falling in some places,
rising in others, and being agitated
everywhere.
3. The volcanic theory, which holds
that the disturbances are due to fires
in the eaTth's center and to their fumes
and steam which force an outlet. In
the hot water, steam and gas elected,
and in the Odors impaired to the
springs II wells they ind evidence of
the truth of their theories.
a. The a~Strononlica theory, which
holds that the cause is to be found in
the attraction Of the planets, derives
argument from the enormous weight of
the extraordinary tides and claims tina
the attraction Of the sun and the moon
operates on the crust of the earth as it
does on the great body of water that
it raises n lowers.
5. The electrical theory, whose fol.
lowers will deduce from the lights,
M G~@ - ,-l S-@1~1;t;~, ~F l-. -.
and from comets and meteors that have
appeared simultaneously with the
earthquake, conclusions favorable to
the origin of the disturbance. from the
subtle and universal agent, electricity,
s. The chemical theory which as
crfbes the disturbance to ferrnenting or
decomposing minerals. The believer in
the conversion of metallic potassium
by rapid inflammation into common
potash in deep recesses of the earth
finds the salt petrous sandstone am ar
gument for his belief in the chemical
theory of earthquakes.
The sound which accompanies an
earthquake has rarely. if ever, been de-
scribed more graphically than by an
observer OF the Charleston earthquake
OF 1856. He was at the tfrae on the
second tloor of a lofty building In
Charleston when his attention was
vaguely attracted by a sound that
seemed to come from the Office below,
and was supposed for Il moment to be
caused by the rapid rolling Of a heavy
body. as an iron safe or a heavily laden
truck. over the floor. Accompanying
the sound there was Il perceptible ire
NOR of the building, not more marked,
however, than would be caused by the
passage Of a car or dray along the
street. For perhaps two or three sec
onds the occurrence excited no surprise
or comment. Then by swift degrees, OF
all at once-it is difficult to say which
the sound dcepened in volume, the
tremor became more decided, the cal
taught the rattle of window sashes, gaa
fixtures and other movable objects. g =
The long roll deepened and spread into
an awful roar that seemed to pervade
at once the troubled earth and the. still
air above and around. The tremor was
now a rude rapid CULVER, that agitateG
the whole lofty, strong-walled build.
ing soon the floors were heavins
underfoot, the surrounding walls anC
partitions visibly swayed to ard fro
the crash of falling masses of stone and
brick and mortar was heard overhead
and without the terrible roar filled tn.
ears and seemed to fill the min ano
heart, dazing perception, arrestins
thought y " . until at last the up.
roar slowly died away in seeming dis.
lance. The earth was still, and oh! tn,
blessed relief Of that stillness!"