The Abilene reflector. [volume] (Abilene, Kan.) 1883-1888, 1885-04-09

| inc ulSlIiCt. Will IC2iSbcI
tions of subterranean activity. During
the continuance of the earthquake the
ground often heaves like the sea, pro-
ducing feelings akin to the familiar
pangs of sea-sickness; rivers seek fresh
channels; large assures open in the
earth, and permanent changes take
place in the geographical features of the
country. Thus the series of earth
quakes which in 1926 and 1927 visited
New Zealand. caused sa~distinct a
change that the former features of the
coast could be no longer recognized.
The earthquakes of the present century
in Chill have produced a permanent
elevation of the coast there; and re-
cent subterranean outburts in Java
have considerably modified the geo
graphy of that region.
| Concerning the origin of these phe-
nomena. so far-reaching in their effects,
it must be admitted that the true theory
has never yet been framed. Early spec
ulations were much tinged with the su-
perstitions of the time: and even so
late as the beginning of the present
century we find a lingering remnant of
this superstitiouS regard of physical
! phen 0mena in the naming, by the in
habitants of Sindree. of a mound
thrown up during the Indus earthquake,
"Ullah Bund," or the Mound of God.
1t is obvious that the study of these
interesting phenomena is beset with
many difficulties. Observation can
often only be made at imminent per-
sonal risk. Yet spite of this, begin
ming with the few observers and the al
most mythical records of the days of
Pl;ny. the fascinating subject has con-
| tinued to attract an ever increasing
circle of students. who have ever more
earnestly endeavored to pierce the veil
of mystery which surrounds it. Each
fresh manifestation of subterranean en-
ergy is now watched with increased in
terest. Whenever possible, the Sc
quence of events is noted with extreme
detail. old theories become weakened.
fresh ideas confirmed. and new avenues
Of thought open themselves to the earn
est investigator at every step.
With the phenomena of earthquakes,
those of volcanoes are closely linked.
volcanic Outbursts being frequently her
aided and accompanied by earthquake
shocks; and there can be little doubt
that the two are most intimately bound
up, if, indeed. they are not two effects
arising from a single cause. This being
so, the facts which surround the one
class of phenomena may be drawn upon
in attempting to frame an explanation
whence and how either originates.
That some portions of the earth's inte
rior are in an immensely heated con-
dition, the nature of the materials
elected from volcanic vents renders ey--
dent, and observation has also clearly
demonstrated the fact that the temper
ature increases from the surface of the
earth downwards. the average increase
being one degree Fahrenheit for every
fifty feet of descent. Now, from con-
Siderations connected with the figure of
the earth and the other members of the
system to which it belongs, it has. with
solar system has evolved from one of
those glowing gaseous aggregationS
termed nebul9, that ''thiS world was
once fluid haze of light" and that
when it first existed as AN Independent |
body it was in state of the most fer |
vent heat. residue of which now gives |
rise to volcanic phenomena.
What happened, then, as our earth
radiated its primitive heat into space? |
The question is a veXed one. So many |
men. so many minds. One class of |!
theorists, not giving sufficient weight to |
the fact that the increase of pressure !
towards the earth'S center would tend /
to keep matter solid there under the in
fluence of high temperatures, suppose !
that the process of radiation by the !
earth into space has, throughout the /
lapse of ages, resulted in the formation |
of a solid external crust covering 4 still |
fluid nucleus. But this class of theorists
is, like the volcanoes of Britain, practi-
caliy extinct, or is at least as subdued |
and unpretending as the Suffolk earth
quake. Other geOlOgists, giving more
weight to the fact of increase of press
ure towards the earth'S center, consider
that its condition is that of body with |
a solid nucleus and a solid external /
crust, between which there still re-
mains a residue of liquid matter.
In objection to both these views it has
been shown that for the earth to maintain
its rigicity under the moons attraction,
ness, of so great a thickness, indeed.
that Sir William Thomson, who investi-
gated the matter, prefers to consider
the earth as solid globe cooling by
contraction. On this view of the earth's
condition, volcanic phenomena are eX-
planned as the result of the conversion
into heat of the mechanical force of
contraction; while earthquakes NAV
themselves be regarded as proceeding
from the crushing and bending of the
rocks by the stress of contraction itself
Again, there are those who regard the
earth as a globe mainly solid through
out, but with lakes of liquid matter in
various parts near the surface, remnants
of its former heat, and believe that it is
from these lakes, as the earth continues
to contract, that matter is forced into
vents to feed their intermittent
fires; whilst, looking at the fact that
so frequently precede an
these earth-tremorS NAV from
this point be regarded as Intellectual
efforts by the pent-up subterranean
forces to establish volcanic outburst:
and since the observations of Mr. Mallet
in earthquake localities have demon
Strated the fact that shocks emanate
from centerS near the earth's surface.
being sometimes nearer, and sometimes
further, as the shocks are mainly hori-
zOntal or mainly vertical in character.
there would seem to be some proba-
bility in this latter view of the origin of
the subterranean forces; but there are
many arguments which initiate against
its acceptance.
There are those also who. while they
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