New-York tribune., 1904-10-26

rlRTHoUAREs ~ THE light OF THE NEW
aSi6smis saS6si IS Sons 3 IS '''D''-''1- ''' ~ -
with tho possible exception OF volcanic 40
fsvsty. no geological phenomenon Is so appalling
or destructive as che earthquake. The lat
ser demonstration of force IS much brfefer than
ne former, and IN point OF violence goes
through q wider range. Sometimes only the
sasnteSt perceptfbls rremor Is detected, and
sometimes the shook is severe enough 70 pros
trate the houses Of city IN an instant A vol
osno seen AZ a suitable distance. is an impos-
ing. not 70 say picturesque. spectacle The
.svsbouate has no such redesming trait Il
NAV be feeble enough to be harmless. but there
a. never anything beautiful about It Indeed
even when Il passes without working serious
injury, grave apprshensions are momentaTlV
excited By q knowledge OF what has previously
happened elsewhere. Hence from time I'M
memorial earthquakes have been the subject
OF almost endless popular and scientific specu-
lation.
Major Dutton shows that while much progress
has been enected In the last thirty years in
the study OF these disturbances they are not
yet fully understood BY means OF instruments
-vhsch have come into use only OF late the
behavior OF the vibrations has been more clear
y revealed than ever before, but the causes
which give rise thereto are still more or less
obscure Nobody questions. for instance. that
a4 least one class OF shocks result from explo-
sions a volcanoes, but even the wisest experts
are yet unable TO tell exactly how those eXplo-
udons are produced Besides. only small pro
portion of the earthquakes appear 20 be related
% volcanic action Furthermore. several 01neF
theories which were once entertained concern
ang them now appear less tenable than formerly
and the scope OF future conjecture IS thus being
narrowed
One OF these discarded hypotheses Is that the
moon exerts an attraction upon the molten
anterior OF the earth. and raises a TIDE there
which creates a temporary strain in the crust
We'll the trouble with that belief IS that geolo-
Rists and seismoogists are pretty well con-
WINGED to-day that the interior OF the globe IS
rigid. Earthquake waves appear TO travel from
the point OF development by two routes. Ihey
not only follow the surface, but also seem to
60 through the middle. which. Of course. would
be quite impossible Il the interior had a pasty
consistency Again. while there may have been
ruggestiys coincidences between the occurrence
Of a Few earthquakes and certain phases Of the
moon, a comparison made with g very much
larger number falls 10 show any preponderance
A favor Of lunar influence. Another notion
which has been discredited IS that there might
be great cavities below the surface into which
the overlying strata fell suddenly. That q
subsistence IS occasionally observed. amounting
70 several feet cannot be questioned, but no
cave has ever been discovered which ap-
peared TO be big enough TO account for the dis
placement which takes place.
The favorits doctrine at the present time is
that strains are set up in the rocky crust Of
the earth which tend 10 shift or bend portions
Of the latter. It is also believed that the stress
gradually Increases until the limit Of resistance
IS reached and then something gives way alb
ruptly. The scene Of this action is below the
surface but II does not frequently appear to be
well defined Major Dutton says that it is q
locus" but not point" although for con-
veniencs It may be looked upon being the
latter From the centrum" as the geologists
call it, vibrations proceed both IN an upward
direction and radialy A third set sometimes
travels so to intersect those moving d.
Tectly away from the centre. Still others ap-
parently traverse the interior. The immediate
effects are generally nothing but tremors. act
ing horizontally. but now and then there Is a
huctuation Of the land like a wave at sea-
Sometimes on opposite sides OF an old cTevice
or one newly formed-the ground win move
IN different directions. horizontally vertically
4 large number Of earthquakes occur near such
cracks faults" and there is ground for
suspicion that the line OK least resistance" fur
nishes the quickest relief to the strain
How the latter originates is just now the
chief puzzle. once II was customary to hold
tho shrinlnage OF the earths interior responsible
SOr the wrinkling and fractUrng Of its shell.
This ingenious and satisfactory way Of explain
ing the Development Of mountain chains the
fracturing and distortion of strata and the
stresses which cause earthquakes is now falling
into dlsrepu1e. a number Of geologists think
that there has been shrlnkage worth men
tioning. and that only a trihing loss Of heat
has occurred through radiation. In fact. doubts
are expressed to-day about the mass ever hay