Watertown republican. [volume] (Watertown, Wis.) 1860-1906, 1873-07-02
The Physical Condition of the Planets.

Whlle the savants of former centuries
nave, with the utmost minuteness, de-
termined all the detailssof the motions of
the bodies which constitute our planetary
system, and definitely settled the asuonom-
lcal aspect Of the question, it was reserved
tor the astronomers of the present day,
the latter half of the nineteenth century,
to determine the particulars of their actual
condition, and to settle the physical as
pect of the question
First of all, astronomy having long ago
proved that our earth contains scarcely
the four hundred thousanrlth part of the
matter constituting our planetary system,
and that she has common origin with the
rest OF the same, the new science of geol-
| ogy proves that our earth had passed
through gradual cooling process, that
| many portions of her surface were to all
1ntents and purposes equal to a burnt up
cinder, while other portions of the sur
face had been disintegrated, washed, dis
solved, precipitated etc, blythe long pro-
longed action Of water. we are, as it
were, driven to the conclusion that the
history of the other members of our plan
etary system must be similar to that of
our earth, that sooner or later they have
gone or will go through the same phases
OF existence, and that the fate in store for
our earth may be learned from the condi-
ton of those planetary bodies which are
the furthest advanced in this slow cooling
process SIS s# 81
The celebrated French naturalist Button
was the first to make experiments in or
der to determine the period of time re-
CURED for highly heated bodies of differ
ent size to cool off by radiation; he had
very large iron balls cast of different
sizes, exposed them freely to the air in
order to cause them to cool down, and
noticed carefully the difference in time
required by the large as compared with
the small ones He thus found the law
regulating the relation between the size
of the ball and the time required for it's
cooling; and, applying this law directly
to a ball of the size Of our earth, in the
supposition that it was once white or red
hot, he found the lapse of millions upon
millions of years necessary for. her cool
ing down to the present temperature.
His experiments were more recently veri-
fed by Blschof in Germany, who had
balls cast of certain furnace slags similar
to basalt; some of these balls were of
colossal size. He came to similar con-
illusions, supporting the evidences of the
geologists in regard to the immensely of
the period of time required for the past
hlstorysof our planet. This consideration
alone makes the now almost Anticipated
idea, that the planets are all inhabitable
at the present period of their existence, if
not untenable at least very doubtful. The
planets are of very different sizes; they
therefore require different periods of time
Tor cooling down, and as they originated
from the same nebulous mass of matter,
q of re
gravitation mot by cooling), nearly the
same temperature, they must now have
reached very different conditions of heat,
which vary according to their sizes. .s~
Let us now see what the combination
of the modern spectroscope, photometer
and telescope reveals to us in this respect,
and whether these conclusions are con
frmed by the mostscrutinous observations
OF the present day. Fortunately one of
the smallest bodies Of the planetary sys-
tenn, and therefore one of those which
must have cooled the soonest, is the near
est to us, our moon. Observations point
to the undeniable fact that, in the moon,
all effects OF its own heat have utterly
ceased, that the whole satellite is cooled
down to low temperature, scarcely
reached on earth by the tops of the Hima-
layas and Andes; that all former volcanic
action, OF which she bears strong evi-
dences, has utterly ended, and that all
water ever possessed by her has long ago
been absorbed by her lavas and rocks as
water OF hydration; while no trace of an
atmosphere can be discovered, SO that we
do not know whether she ever had one,
The next body of which we have some
definite knowledge is the planet Mars.
Although he is at several hundred times
greater distance from us than the moon
we can observe his atmosphere, clouds.
changes of seasons in his two hemispheres
by the periodical increase and decrease of
the ice belt around his poles. In fact
there is no heavenly body in which the
conditions are SO similar to those of our
earth at the present time; but the planet is
much smaller than our earth, and is fur
Their from the warming influence of the
sun; therefore the probability is that he
is farther advanced in the cooling process,
and this is confirmed by the closest mod
ern observations. Clouds and water are
much more scarce there than on our earth.
and the fate awaiting us, Of drying up of
vegetation by want of sufficient water, has
commenced to be realized there on a large
scale, as on our earth it is realized over
limited surfaces, such as the Asiatic and
In order to understand the reason of
this continual diminution of the amount
OF water on planet, we have only to con-
slider that after every volcanic eruption, by
the hydration of the cooled lavas, certain
amount of liquid water is withdrawn
from the general provision and solidified in
the rock, and that the liquid interior of
our earth contains enough to absorb many
times all the water Of our oceans; as these
extend down scarcely the one thousandth
part of the earth's diameter, while only a
comparatively thin solid crust covers the
hot interior. These two bodies the moon
and Mars, are thus ahead of the earth in
history, while the other members of the
system are behind. Jupiter, by reason of
his immense size, 1000 times that of the
EARTH is not yet cooled below the red heat.
and is surrounded by an atmosphere of
superheated steam, as we mentioned on a
former occasion; Venus by it's neighbor-
hood to the sun, being nearly of the same
size as our earth, is in very much the same
condition as Jupiter only cooled down a
little further, and on the eve of becoming
tit for vegetable and animal life. Of Mer-
cnrV still npor9r To tho orr, --o