New-York tribune., 1906-04-21
NEW THEORY OF CAUSE.
Professor Stevenson Suggests Tol-
canic 4cti1aty an Sierras.

Professor John J. Stevenson. OF the department
of geology of New York University yesterday ad-
vanced a new theory of the cause of the San Fran
cisco disaster when he suggested that the earth
quake night be due TO sudden activity in the vol
canic regions Of the Sierra Mountains. These
mountains form link of the great volcanic chain
which runs from Chill. in South America, 70 ia
pan. with only a few breaks The great extinct
volcanoes of Alaska in this belt and all Cali
fornia is included in it.
Professor Stevenson said:
It must be understood that am not speaking as
a volcanologist My work has, been chiefly in
stratalOgical geology, and in SO far ! speak Of
observeT have naver thank COD wnasad mrs. daa1 m
earthquake. nor nave I ever been on hand TO make
an immediate investigation of such phenomena.
quakes To these the present disasters have inclined
to think another might be added which would
in California. bristltng with extinct craters of
canic activity beneath them would be required to
tlow the plug out of one OF these Craters-the aC-
means suffce-and il is conceivable that the earth
quake which has devastated san Francisco might
Tnor nrobable IN lev f the fac+ tI9at in The bis
tory of volcanic eruptOns violent earthquakes have
often preceded the eruption ceasing altogether with
the opening of a vent for these natural forces.
Two other explanations may account for the dis
aster. There is less contraction constantly
going on in the earth beneath the outer crust, as
the originally molten matter continues TO cool
Great disturbances Of former ages have left many
,iaults IN the structure OF the earth's crust ana
the contraction of the inner matter causes period
tcal adjustments of strata. The coast or California
Is comparatively new land and the earths crust IS
thin and full OF faults. which necessarily in
process Of frequent adjustment. There is no doubt
that the frequent minor shocks recorded the
Pacific Coast are due to this cause. but the magni-
tude OF the present quake leads me TO think tnat
there is something in the idea OF volcanic actiVly
There is third possible explanation. The deep
sea basin Of the Pacific begins at point very near
drops only about seven feet mile for a distance
Of eighty miles when there Is a sudden daa. s4feT 4o,
droD occurs much nearer 70 the shore The inter
vening space between the shore and the basin
in its character. and much Of San Francisco ana
other towns built upon rock Of this kind
7 have spoken of sometimes cause this rock 70
slide along toward the ocean for several yards at
planation Of the Charleston earthquake, in 1886.
fail TO how II Is possible 10 prove the theory
spots with the earthquake I will not attack the
idea, but as I say, simply cannot conceive or any
regard he idea that the eruption OF vesuvius
is connected with the California earthquake er-
roneOus- Such connection would imply the eN-
istence Of a lake OF fire extending from Nesuvtus
California II is like PerTys theory that earth
quakes are due 10 tidal movements in the molten
interior of the earth. cOujointly affected by the sun
and moon This might be all right Il we knew that
interior Of the earth is Of fire. which we
do not All know is that there are lakes Of
As TO New York ] know OF nothing which should
alarm the most hysterical person. New York CITY
is built upon some Of the oldest material in the
world. The crust thick that the adjustments
Of faults and OF the are hardly to be telI AZ
all There is record Of an earthquake In lSsi pow
erful enough dslodEe bottles from shelves
New Yorks vicinity since the erection OF the Pan
sades- This occurred AZ time 50 far back tLlat
in the Reptilian age. before any mammals lived
think that further severe shocks in San Fran
of a tidal wave unless there is another shock
wave is Immediately connected with the shock