The morning call., 1891-08-10
nARrHoUAKE ON A SMALL SCALE.

There appears to be no doubt that slight
earthquake, followed by tidal wave, al the
head of the Gulf of California, did take
place on The 30th of July. The accounts OF
the phenomenon, which were published in
sensational sheet, were so obviously mac
curate and exaggerated that people gener-
ally disbelieved the whole story but 1t
seems certain that some seismical disturb
apce did take place on that day in the coun-
try occupied by the Cocopah Indians, and
that there was some injury done to buildings
and fences in the new colony of Lerdo.
The event would not be strange. though
the geology of the country through which
the Colorado flows indicates that severe
earthquakes have not occurred in that re-
gion since the present geological era began.
But the whole of the depressed plateau
which spreads from the Gorgonio Range in
Cal ifornia to the NaZareno and Carrigal
ranges in Sonora is apparently covered with
a thin crust under which volcanic agency is
active. as the abundance of solfataras proves.
II is like the hollow which Lake Nicaragua
partially fills, Il sort of sink, surrounded by
moEntains and covering body OF Subter-
ranean fires. In parts of this sink minia-
turc volcanoes, ten to twelve feet high and
with craters from two 10 ten feet wide, con-
staBtly bclch gases, water and sulphur in
various combinations. There are said to be
spots in which thousands of them are in
sight together. In Nicaragua the subterra-
mean forces have no such vents, ana when
they become ungovernable they relieve
themselves by eruptions from the great vol
canoes. In our desert the work is done by
an infinite number OF small safety valves.
1t is interesting TO observe the gradual de-
cline in volcanic activity on this Coast.
Mounts Shasta, Food and Tacoma were
Irobably active volcanoes within the his
toric period. They are now nearly extinct
Almost within century PortOla, whose
cross still lies athwart the setting sun,
averred that his troopers were knocked
down by earthquakes on their march along
the coast from San Diego. In our time it
takes close observation to detect an earth
quake on any part of the coast. In Mexico,
with the single exception of Torulo, which
erupted twice in the last century, most of
the old volcanoes which used 10 terrify the
Toltecs are now silent Not until the trav-
eler reaches Guatemala does lie find a coun-
try where the agOnes of the earth create
alarm.
Humboldt satisfied himself that there was
crack in the earth's crust extending
through the Continent about the lire of 1872
north. Such a line would pass through
Popocatepetl and Colina, but would run
some thirteen degrees south OF the present
head of the gulf Of California. Still, The
numerous mud volcanoes of the Colorado
Desert and tie geyseTs in Son0ma County
prove that at these points the surface of
the earth is nearer the subterranean c.ul-
drons than in any other parts of the State.
But there is no record OF any volcanic up
heaval at either point. Thin as the crust
may be there, il must be thinner somewhere
else.
Whatever changes may be taking place in
the region which is washed by the gulf of
California and its affiuent, the Colorado
River, are the working Of water and not of
fire. That both gulf and river are changing
their channel is quite possible. Geology
shows US that they have done sn before.
But there are no traces of volcanic up
heayals. OF course, the fact that a natural
phenomenon is Unprecedented is not proof
that it is impossible. Tie part which vol
canic agency has taken in the work of crea-
ton is not complete; only the other day it
submerged an island in Angler Straits and
sank whole coast line below the surface
Of the waters. What it did there it may do
elsewhere. The admission of Humboldt's
theory Of a CT ack on the line of I9o does not
involve an assertion that there are no cracks
elsewhere. Still, from all present appear
anceS, the event of July 30th does not seem
TO warrant alarm. The people of Yuma
may retire TO their beds at the usual hour
and sleep the sleep Of the just without fear
ing that their waking may be prevented by
q cataclysm Of nature.