The Hawaiian gazette. [volume] (Honolulu [Oahu, Hawaii]) 1865-1918, 1869-03-10

been presented as irrelragAote proofs Oh ine
incandescent and liquid state Of the globe
in former times Now, it is fact that a
liquid sphere, turning on an axis, viii
necessarily assume this form. on account
of the unequal swiftness of the different
parts Of its mass but it may be well to
inquire whether globe, even solid, would
not become hAttened at the poles and in
nsted at the equator, when spinning inces-
sanity for an indefinite series of ages, for
it is well known that there does not exist
any matter entirely inhexible, and that,
under the heavy pressures obtained in our
laboratories, (which are infinitely inferior
in duration to the pressures of the plan
etary forces all the solid bodies, such as
iron, steel, &c-. ooze away in the same
manner as liquid bodies. On the other
hand. the observations and calculations Of
astronomers and geometricians have led
them 10 believe that the fattening of the
earth at either pole is subject TO certain
variations, and that consequently there
are laws. differing from those Of rotation
and revolution, which would contribute to
modify the form Of the earth. The irregu-
larity Of the sphere seems to have been
subjected to some periodical changes. dur
ing the course Of ages. and is even con-
plicated by some other Irregularities
gescences and depressions-revealed to
the geographer and astronomer by the
oscillations of the pendulum and the meas
urement of terrestrial meridians. If the
cause Of those changes is still unknown,
at least there is no reason leading US to
believe that they are due to the centrifugal
force developed by the rotation Of the
earth.
We must also bear in mind that in the
hypothesis admitted by those who believe
IN the central fire. our planet is TO be con-
sidered as liquid mass. since the exterior
envelop is comparatively thin pellicle.
| Under these circumstances, it is difficult
to understand how this ocean of lava is
not sgitated, as is the ocean of water, by
alternate tidal movements, and does not
lift up, twice day. the slender film float
ing over it. 1t is likewise matter of
surprise that the earth is no more de-
pressed at the poles than it is. and has not
the shape of disc, and yet the Aattening
of the poles is not greater than the differ
enees Of level on the surface of the earth
in the equatorial zone, between the sum
mits of the Hinalayas and the abysses of
the Indian Ocean. Let Us mention also
that in recent book published by Mr.
Emmanuel Liais. the celebrated astrono-
mer assigns this slight fattening to the
ineessant erosive work, for ages. of the |
polar water and ice, which, being ire
sistibly attracted towards the equator,
carry along with them enormous quantities
of debris torn away from the surface.
The main argument brought forward by |
those who think that the existence of a
central fire is an undeniable fact, is that in
the different layers of the earth's crust |
explored BY miners. the heat increases
with the depth arrived at. In descending
the shaft of mine, one invariably trav-
erses zones of higher and higher tenn
perature, but the rate of progression varies
for different places and according to the
nature Of the rocks in which the shaft has
been sunk. Mr.. Bischoff, the chemist,
who has made these questions the study
Of his life, informs US that the heat in.
creases more rapidly in the schists than in
the GRANTEES in the metallic lodges, than
in the schists; more in the copper veins
than in the tin ones, and more in the an
thracite layers than in the metallic rocks
The average interval which, in this great
thermometer of the terrestrial layers, cor
responds to one degree of heat, is from 25
to 80 yards
But the earth has not been excavated
to any great depth. and the most remarka-
bic cavities known-those of Kuttenberg,
in Bohemia, and one of the mines of Gu
anajuato, IN Mexico-have hardly reached
1000 yards, that is to say, the 6-l,0OOth
part of the earth's radius, and nowhere
has the miner had to bear more than As
eentigrade of heat. 1t would, therefore,
be hasty conclusion, if we were to Judge
of the state of the central part Of the
globe from the temperature Of the super
fetal strata. and to hold that the heat in
ereasing in constant proportion from the
surface to the centre, must therefore be
there 100000 degrees, which is far above
what the Imagination of man can con-
ceive. One would be as much justified in
concluding from the gradually increasing
cold of the high aerial layers, that the
temperature becomes lower and lower, in
constant proportion, up to the middle of
the celestial regions, and that at 1000
kilometres from the earth, the cold must
be 5,OOOe- The superficial part of the