The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1884-08-17
EARTHQUAKES.
Scientific Belief that They are
Caused by SHbsidency, Not
Explosion.

Professor Samuel Kneeland, An,
NJ. D., of Boston says,in lecture en-
earthquakes:
The old theories of the causes OF
volcanoes have gradually lost the con-
Gdence OF biologists. Mallet's theory
is now generally admitted as the best
explanation, to wit, that, in cooling
from a highly heated nehulous matter
the crust CT the earth has shrunk
upon the centre, more readily accord
ing to its thinness, and the most 30,
tn refore. in former geological ages;
this shrinking and falling in OF strata
OF immense extent and thickness, by
the motion, deveiC ped a great a mount
OF heat sufficient to melt rocks and
the sedimentary 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 fac that the hight
of the lottiest mountains aud the
depth of the deepest ocean are about
alike. AS connected with the cause
of earthquakes here maintained. it
may be mentioned that che 1894
eruption OF Vesuvius yielded
46. 600, 600 cubic feet OF lava, that OF
Atna, in 1869, twice that amount
and that of Skaptar Jokul, in Iceland,
in two years, twenty cubic mile.
Where the heat generated by fiction
of subsistence ia not sufficient to
liquify 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 expect the earth
quake, as q rule, you need not fear
an outburst.
The theories of earthquakes are
numerous and fancifulin the extreme.
No satisfactory connection with
atmospheric conditions has been
proved, except as mere accessory;
they occur everywhere. at all season!
of the year and in all geological for
nations and times. They seem tl
follow no laws of periodicity, aid ars
apparently independent OF volcanoes
The theory OF their nature usually
accepted now is that of Mallet, viz.
that an earthquake is passage OF {
wave past an observer, in any direc
ton, with q force and velocity
depending on the activity ofthe cause
and the nature OF the strata through
which it passes-s vibratory move
ment, like that of wave OF sound
transmitted, reflected and refractec
by the earth; it may originate beneath
the sea, causing a destructive tids
wave hundreds OF miles distant. Thi
wave can be measured by cunningl!
devised instrument.
| Having visited the earth. quak
districts of Iceland, the Sandwich ami
Philippine Islands and the Mediter
ranean basin, l am OF the opinion
that almost all extended modern
earthquakes have been the result O
subsistence, and not OF explosions.
| Wherever, in the cooling, shrink
ling crust, support is taken away b.
contraction, pressure, chemica
action, emission Ct lavas, corrodinI
land heated waters, occasional exolo
sions. aided possibly by terrestrial
meteorological or Astronomical
causes, the strata fall in; these ma.
| be hundreds OF miles in extent ant
leagues in thickness, with more o
less violent depression, producing q
| shock which may be transmitted t
great distances by land or beneath
1.-THE water. In certain fractures o
the crust, produced Uneven the remot
geological ages and in favorable strata
much heat and consequent chemica
faction may liquify the SURF oundini
rocks and cause a flow OF lava. Thi
Undermining or corrosion I conceiv
| to be the predisposing cause of earth
lquakes, the shock being the effsc
carried for long distances, with a vic
lence and direction depending OH tn
Ielastic character OF the strata.
| In old geological times the disloca
tions or up-liits of STRAIT, cslle'
"faults, "were doubtless accompanies
| by earthquakes and were then thei
| most common causss; hut in III
tension and pressure which formed
the then immense folding have il
great measure ceased, subsidenc
may be more satisfactory explana