The Caldwell tribune. [volume] (Caldwell, Idaho Territory [Idaho]) 1883-1928, 1884-08-23
EARTHQUAKES.
"A Scientific Belief that They are Caused
by Snbsidency, Not Explosion,

Prof. Samuel Kneeland, A. MN.
OF Boston, says, in q lecture on earth
quakes:
The old theories of the causes of VOL
canoes have gradually lost the conf
dence of biologists. Mallet's theory is
now generally admitted as the best ex-
PLANTATION, to-wit, that, in cooling from
Il highly heated nebulous matter. the
crust OF the earth has shrunk upon the
center, more readily according to its
thlnness, and the most so, therefore, in
former geological ages; this shrinking
and falling in of strata of immense ex-
tent and thickness, by the motion, de-
velop great amount of heat, suffi-
cient to melt rocks and the sedimentarv
deposits between the crust and the
nucleus, which, by the agency of steam
from admitted waters, are brought to the
surface in the form of lavas.
That the same cause has produced
both the elevations and depressions on
the earth's surface may also be inferred
from the fact that the hight of the lofti-
est mountains and the depth of the
deepest ocean are about alike. As con-
nected with the cause of earthquakes
here maintained, it may be mentioned
that the 1894 eruption of Vesuyius
yielded 10000, 900 cubic feet of lava.
that of Etna, in 1869, twice that amount
and that of Skaptar Jokul, in Iceland,
IN two years, twenty-one cubic miles.
Where the heat generated by fiction of
subsistence is not sufficient to liquefy
the rocks, mud volcanoes, as in Java
and Hawaii, are produced; and as the
volcanic energy lessons, geysers and
hot springs denote the expiring forces.
Though in such localities you may ex-
pect the earthquake, as rule, you need
not fear an outburst.
The theories of earthquakes are mum
erous and fanciful in the extreme. No
satisfactory connection with atmos-
pheric conditions has been proved, ex-
cept as a mere accessory; they occur
everywhere, at all seasons of the year
and in all geological formations and
times. They seem to follow no laws of
periodicity, and are apparently lnde-
pendent of volcanoes. The theory of
their nature usually accepted now is
That OF Mallet, viz, that an earthquake
IS the passage OF wave past an OBJ
server, in any direction, with a force
and velocity depending on the activity
u the cause and the nature of the strata
through which it passes-a MIGRATORY
movement, like that of of sound,
transmitted, reflected and refracted by
he earth it may originate beneath the
ca, causing destructive tidal wave
of miles distant. This wave
an be measured by cunningly devised
Having visited the earth-quake-rent
istricts of Iceland, the Sandwich and
'hllllppine Islands and the Mediterra-
can basin, am of the opinion that
lmost all extended modern earth
uakes have been the result of subsi-
ence, and not of explosions.
wherever, in the cooling, shrinking
'ust, support is taken away by con-
action, pressure, chemical action,
MISSION OF lavas, corroding and heated
alters, occasional explosions, aided
ossibly by terrestrial, meteorological
astronomical causes, the strata fall
d.; these may be hundreds of miles in
tent and leagues In thickness, with
ore or less violent depression, pro-
icing shock which may be transmit
to great distances by land or be-
'ath the water. In certain fractures
the crust, produced even in lemote
illogical ages and in favorable strata,
UGH heat and consequent chemical ac-
m may Equefy the surrounding rocks
d cause flow of lava. This under
ming or corrosion l conceive to be
predisposing cause of earthquakes,
shock being the effect carried for
lg distances, with violence and di-
'tion depending on the elastic char
-er of the strata.
In old geological times the disloca-
rs or up-lifts of strata, called
lults,' were doubtless accompanied
and were then their
st common cause; but, as the ten
a and pressure which formed the
n immense folding have In great
asure ceased, subsistence may be
re satisfactory explanation than up
val.