The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1894-02-14
TREMORS OF THE EARTH.
Some Great Quakes Which Have Been Felt
in the United States

There have been three great earth
quakes in the United States during the
present century," said Prof Gilbert, the
geologist, to Writer for the Star. "One
that was very remarkable occurred in
1911 and 1912 near the head OF the delta
of the Mississippi 1t embraced num-
Der of severe shocks at short intervals
during several months In fact, the dis
turbance lasted for about two years.
The ground was moved in visible waves,
by which the trees of the forests were
rocked and in some cases uprooted, their
branches being SO entangled that it was
impossible to separate them.
"Great cracks in the earth yawned and
closed again at each shock, while from
the assures mud as thrown into the air
SO violently was to lodge in the branches
of trees. Some lakes were drained by the
escape of their water into the chasms
which were opened, while others were
created by the sinking of the land. One
great Sunken area thus produced was
so miles long by 35 miles broad.
aThe other two big quakes to which
refer occurred SO lately as to be remem-
bered by the present generation. One of
them happened in the Inyo valley OF
California. 1t was caused by renewed
movement on what we biologists would
call great fault-plane at the eastern
base of the Sierra Nevada mountains.
In that part of the world there is extern
sive 'faulting' in the structure of the
mountain ranges, each range consisting
of one or more huge blocks of rock
bounded by faults and lifted above it's
neigh bors. A fault is made by the sink
ing of one mass of rock in such a man
ner as to change the relation of it's ele-
walton to that of mass adjoining. 1.-The
creation of such faults is often inciden-
tai to earthquakes. A renewed move
ment along the great fault line of the
1nyo valley in 1872 produced a tremend-
GUS seiznic diStur bance. The shocks
continued for fourteen months. Great
assures were formed along the base of
the mountain range for distance of
forty miles, the land west of the fault
rising and east of it falling several feet.
A fence was parted for distance of
fourteen feet in one spot. Owens river
was temporarily swallowed, and numer-
GUS other phenomena excited the aston
ishment and alarm of observers.
"The memory of the Charleston earth
quake of 1876 is yet vivid The focus of
the disturbance was about fifteen miles
west of the city. Numerous big cracks
ODClCO III GAO Cttl Uu VI UAO
country. Water and mud we're thrown
up, and railway tracks We're dislocated
and buckled. The first great shock last
ed for about minute, Others following
with gradually decreasing violence. At
the end of four weeks they ceased to be
destructive, but tremors were felt occas-
ionally for several months. Twenty
seven people were killed outright.
1.-THE invention of the delicate record
ing instrument called the 'seismograph'
has revealed the fact that earthquakes
are far more numerous and freQue
than used to be imagined. In some parts
of the world feeble shocks occur almost
daily. Probably there is no part of the
earth where they cannot be detected at
short intervals. One of the most remark
able quakes of this century took place in
Chilli in 1928. On that occasion several
hundred miles of the coast were lifted
mum Der of feet 1t has been reckoned
that enough rock was thus elevated to
make mountain the size of Mt. Etna.
"The Charleston earthquake was felt
distinctly at distance of 900 miles.
A comparison of time showed that the
shock travelled at the rate Of 1900 feet
second. The tissues in the earth's
crust, which are among the most terri
flying OF seismic phenomena, must be of
great depth sometimes, though nobody
has ever tried to fathom them. They
have been known to swallow rivers for
days without being filled up. Severe
shocks are commonly accompanied by
sounds like explosions near or distant.
Quakes under the sea produce waves on
the surface like those created bya peb-
ple thrown into pool, and sometimes
such waves rush up on the land, doing a
great deal OF damage.
aThere has been much dispute as to the
causes of earthquakes. They are often
associated with volcanic phenomena.
When the lava of volcano contains
much water, the latter is converted into
steam and produces explosions which jar
background for miles. The explosions of
the great mine at He'll Gate, in New
York, occasioned tremblings of the earth
which were observed Us miles away
Washington Star.