The Middlebury register and Addison County journal. [volume] (Middlebury, Vt.) 1883-1885, 1884-08-29
WHAT EARTHQUAKES ARE,
HOW THEY TRAVEL AND THEIR
TERRIBLE WORK.
Phenom ma of the MARTINS Upbeavals
Ultimately Connected with Vol
CnniC ErmpiiOnH-SOmr XiaitntiOnS.

PhenOm ma of the Enrth,s tJpheavaIs
Intimately Connected with Vol
cnnic Ernpiions-Some Visitntions.
Earthquakes, or the shaking of the
solid ground by natural causes, have
been described and their causes theorized
upon since the time of Aristotle. Where
the commissions have been severe whole
cities have been destroyed, fertile plains
laid waste, and innumerable human lives
sacrificed. Sixty thousand persons were
killed in the earthquake that overthrow
Lisbon in 1865, and 100. 900 in the great
Calabrian earthquake of 1888. 1.-THE
Earthquake Catalogue of the British as
sociation," very complete record en-
braces between 5000 and 1000 earth
quakes between the years 1906 B. G. and
A. d. 1912, in which it is estimated
13, 1000, 900 people have persisted. The
phenomena ate ndant upon earthquakes
are as various as their extent is broad.
Appearances in the heavens or changes
in the atmosphere, Irregularities in the
seasons, sudden gusts of wind, inter-
rupted by sudden Gains, violent rains at
unusual seasons and reddening of the
suns disc have all been described rs in
cidental occurrences, but it is doubtful,
in the absence of any good reason to the
contrary, if they have any real connec-
ton with the earthquake. Not so with
underground noises, which always pre-
cede accompany or follow shock. In
some earthquakes they are likened to
chains being pulled about, increasing to
thunder tones; in others the sound is
like the rumbling of carriages gradually
growing louder, until it equals the loud
est artillery, or like heavy wagons roll
ing on a road, or distant thunder, or like
the Kissing produced by the quenching
Of masses of hot iron in water or like
the rush of wind underground.
The most intimate earthquake phenom-
snon is, of course, the shaking of the
ground. Sometimes, as yesterday, it is
gentle. In severe earthquakes there is
almost invariably trembling, then pro-
bounced shock and then trembling
again, which gradually grows impercep-
tible. The whole area of the surface
Affected is not moved at once, but by an
earth-wave or true unduation of the solid
crust of the earth The influence Of this
,arth-wave is often communicated to the
sea when the earthquake is near the shore.
The sea swels and retires slightly from
The beach and then great wave rolls in
upon the shore At the Lisbon earth
quake this wave rose to height of sixty
'eet at Cadiz.
The phenomena of these upheavals
and of volcanoes are most intimately con-
nected. Although the earth must be
mainly solid, it is believed to be honey
combed structure, and that the cavities
contain in many places lakes of molten
rock, between which and volcanoes are
orifices of communication. Into these
cavities water, sinking down through
;revices from the ocean or the land, must
be constantly finding its way, and the
steam thus generated exerts such cnor-
nous pressure as to force the molten mat
ter to the surface, itself mingling and es-
Gaping with it. When a mass of water
is suddenly precipitated into hot cav
ern the explosion of steam will cause an
earthquake conclusion and where there
is no vent may be sufficient to convulse
and rend the superintendent strata.
No part of the earth's surface is free
from these terrifying visitations, and the
ocean itself is not free from them. On
October 10, 1870, occurred the most con-
siderable shock that has been observed in
our Middle and Eastern States during
the present century. The source of this
disturbance has been traced, with some
probability. to the volcanic region fifty
to one hundred miles northeast of Quebec
From this region the shock spread to St.
Johns, n. T., and thence was felt west
ward to Chicago and southwark to New
York, The velocity of the wave or shock
was about IA, 900 feet per second. The
occurrence of the shock felt at Quebec
was telegraphed to Montreal in time to
call the attention of the operators in the
latter city to the phenomena about thirty
seconds before the shock reached them.
The most severe earthquake that has
been recorded in the Middle and Eastern
States was that of November IS,
1855. 1t was probably promulgated
stroyed Lisbon two weeks before In
Massachusetts, it began with a roaring
noise like thunder, and then came a
swell of the earth like that of a long
rolling of the sea- swell so great that
men in the open fields ran to seize some
thing by which to hold on lest they
should be thrown down. In Boston
many buildings and chimneys were de-
stroyed, and in the country new springs
f water appeared and the stone fences
were demolished.
In 1911 occurred the famous earth
quake of New Madrid, Miss, which
created the so called sunk country" in
the valley of the Mississippi, while Cali
fornia has frequently suffered. The
earthquake of March 20, 1872, was the
most severe that has occurred there in
many years, as immense damage was
done in San Francisco by the cracking
of the walls of fine buildings. In Mexico
and South America earthquakes are al
most as frequent as revolutions. -NO
York Journal.
Shnyraru