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“150
fbactoss MARS.
nary be: Loe,
yoo: THE! PLANETS; f
0 “ape pay inmasrreD wortps | |
bog iviy o's y 0, CHAPTER IR pyr :
-Sketch of the Outlines of Continents and Oceans, and the
, Snow Region of the Polar Circle on the Southern Ilemi-
; Sphere of the Planet, Mars, from the observations of
LoMadler, po ents a
-" Yy the absence of an atmosphere we could have
“no clouds; day would be’ one, unvaried wearisome
glare of the sun. ‘ The bright azure sky, so grateful
to the sight, is nothing more than the natural color
-of the air reflected to the eye. * The air which fills a
room is not perceived to be blue only because it is
not present insufficient quantity to excite in‘the
eye any perception of its color; just as a’ glass of
sea-water seems translucent and colorless, while the
same water viewed through. a considerable depth,
appears with its proper hue of green.-;) «> =! 5 =)
_. When we look up, therefore, through forty miles
of air, we behold that fluid of its proper tint of blue.
In the absence of the atmosphere the great vault of
the heavens would present one unvaried and eternal
black, the stars dimly twinkling here and there, the
whole forming a most funereal contrast- with: the
’ bright orb which would be seen holding its solitary
course through this eternal expanse of darkness.
‘The atmosphere produces effects on the tempera-
ture of our habitation which are not less important.
It retains and diffuses warmth, whether proceeding
from the sun above, or from sources of internal heat
within the globe itself What situation with respect
to temperature we should be placed in by its ab-
sence, or even by a consideravie diminution of its
quantity or density, may be easily inferred by con-
sidering the state of those parts of the earth which
are placed at such an altitude as to leave below thema
large portion of the atmosphere. The summits of
lofty ridges, such as those of the Alps, the Andes,
and the Himalayah, are examples of this. No in-
tensity of direct solar heat can compensate for the
absence of a sufficiently dense atmosphere, aud even
within the tropics, water cannot exist in a liquid
form at elevations aboye 14,000 feet. The summits
of the Andes are clothed in everlasting snow.
Had we, therefore, keen unprovided with an at-
mosphere, or even had our atmosphere been so rare
and attenuated as it is at an elevation of three miles
(scarcely one-tenth of its whole height), the waters
of our oceans would have been solid. Vegetation
could never have existed, and in spite of the light
and genial warmth of the sun—in spite of the grate-
ful changes of season—in spite of the beautiful and
simple provision by which spring succeeds winter,
and is followed by summer and autumn, the earth
would have been a barren and arid waste, enveloped
in a shell of eternal ice, devoid of life, motion, form,
and beauty, Tae -
Sceing, then, how necessary to the existence of
an animal and vegetable world an atmosphere is—
how indispensable its presence is to a society of
creatures whose means of intercommunication is
sourd—and yet bearing in mind at the same time
that this atmosphere is not essential to any of the
great mechanical functions of the earth in the econ- :
omy of the solar system—considering also that with- i
out its presence the part which that earth, as.a
whole, performs in the society of the planets, would
~ be the same as it now is—can we come to any other |
conclusion than that this atmosphere was cast
around the earth expressly with a view to the weli-
bea a
sling, and © evenin
FRANK LESLIE’S’NEW- YORK JOURNAL.
being of its occupants—to afford them
a genial warmth—to: give! them: dif-
» fused and gentle light—to convey the
' varieties of, sound—to. promote and
- facilitate social felicity, by, supplying
‘the means of intercommunication by
language—to preserve the seas liquid
‘—and supplying propitious winds to
stimulate the ‘iniercourse of. nations
and knit together the races. of beings
who occupy .its .most- distant’ points
by the kindly bonds of reciprocal bene-
ficence?. 1f, then, such be admitted
to be some among the: many of. the
.. purposes and uses of our atmosphere,
the question whether other planets, in
| situations resembling ours, are occu-
"pied by similar beings, must be mate-
rially influenced by the result of an
investigation. as: to whether or not
these planets are supplied with like at-
mospheres. 6 0
. » Telescopic observations have, most
clearly and satisfactorily answered this
question. » The, atmospheres ‘around
the planets are as palpable to sight as
the clouds which float on: our’ own.
Venus and Mercury areenveloped in
ee
thick atmospheres : in the former the air.is espe-
cially conspicuous, nay, we can even see the morn-
i twilight in that distant world.
The atmosphere of Mars is likewise apparent... We
see the clouds floating on it. ~*~ oe
he ascertained existence of clouds in the planets
proves more than the mere presence of atmospheres
upon them. . An atmosphere is. necessary to sup-
port clouds, but must not be identified with them.|
Clouds are no more parts of the atmosphere than the
mud and sand which float in a turbid river are parts
of_its waters... Water is’ converted into vapor by
the agency of the sun and wind. This vapor, when
it escapes from the surface of the liquid, is gene-
rally lighter, bulk for bulk, than that part of the
atinosphere: contiguous to it.. .It rises into more
exalted regions, where, by the agency of cold, and
by electricity, it is made to resume its liquid state,
but in such minute particles that it floats and forms
those semi-opaque masses called clouds... Clouds
are, then, in fact,.water existing in a very minute
state of mechanical division, and alfected in peculiar
ways by. electricity... /; 0. jh Ss eee fh Sees
- When these particles are caused to coalesce into
drops or spherules of water—an effect which may
arise from temperature or electricity, or both com-
bined—their weight renders their further suspension
impossible, and they descend to the surface in the
‘orm of rain : or if the cold be so great as to congeal
the particles before they coalesce into globules, they
descend in the form of snow :.or, finally, if by the
sudden evolution of heat caused by electrical infu-
ences their solidification is effected in drops, they
comedown in the form of hail. *.
Thus wherever the existence of clouds is made
manifest, there waTer must exist; ¢here EVAPORA-
TION must go on; there ELECTRICITY, with its train
of kindred phenomena must reign; there RAIN must
fall ; there a1. and snow must descend. -
That healthful and refreshing winds agitates the
atmospheres of the group of worlds in the centre of
which our sun presides, and of which it is the com-
mon bond—that showers refresh their surfaces—
that their climates and seasons are modified. by
evaporation—-that their continents are bounded by
seas and oceans—that intercourse is facilitated ‘by
winds which convert the surfaces of their waters
into highroads for nations—these and a thousand
other consequences of what has been here explained,
all tending to one conclusion—that these various
globes are placed in the system for the same pur-
pose as the earth—that they are, in fact, the dwel-
lings of beings in all respects, even from their low-
est physical wants to their highest social advan-
tages, like ourselves, crowd upon. the mind so
thickly that we can scarcely give them expression
in a clear and intelligible order. , ‘ -
It may be asked whether by immediate observa-
tion we may not perceive the geographical surfaces
of the planets, so as to declare by direct survey
their divisions of land and water, mountain and
valley, and other varieties of surface. me
~. Even the most superficial view of the subject wiil
render apparent some great difficulties which must
obstruct such an inquiry with respect to most‘ of
the planets. The-very presence of those atmos-
pheres and the clouds with which they are loaded,
olfers.a serious obstruction to any observations
having for their object to ascertain the geugraphical
character of their surfaces. The great distance of
some of them is a formidable obstacle to suck an
inquiry ;{ still; where some: peculiar circumstances
favor the cbservation, something has been done in
this investigation.” 2 sacri ie fate oe
_ Venus and Mars, the two planets in the system
which come nearest to the path of the Earth, are evi-
dently the most eligible objects for such an irquiry,
and sufficient has been ascertained, especially with
regard to the Jatter planet, to draw very closely in-
deed the ties of analogy. by which the planets ‘are
associated with the earths «(8 fy ny s2.)8 st)
.| The existence of continents and oceans, and even
the configuration of their outlines has been clearly
traced on Mars.. The snow which covers his polar
regions during the winter, has been distinctly seen,
and has even been observed partially to dissolve and
disappear under the influence of the summer heat.
The clouds with which Venus and Mercury are 80
constantly enveloped, combined with other obstruc-
tions, peculiar to the positions of these planets, have
rendered like observations respecting them imprac-
ticable. It has, nevertheless, been ascertained that
their surface, like that of the Earth, is marked by
mountain-chains of great elevation. » °°). t
In tracing the analogies which prove the suitable-
ness of the planets for habitable globes, and which
connect them by ties of kindred with the earth, one
of the most important and interesting, is dependent
upon the‘ quantity of matter composing these plan-
ets, compared with their volumes or bulks. Let us
see how this affects the condition of the organised
creatures that dwell upon them... - 27." =. 5.2
All organised beings, whether animal or vegeta-
ble, are endowed with a‘certain limited. amount of
bodily strength. .In the case of. animals, which
have powers of locomotion, this strength is regula-
ted with reference to their weight, and the extent
and quantity of motion necessary for their well-be-
ing on the surface of the globe.*, The structure of
every animal is such, in the first place, as to give it
strength to support and move its own body ; but
this is not enough—it must have a further amount,
of disposable force to enable it to. supply its own
wants by the pursuit of its prey—by the collection
of its food—by the erection of its dwelling ; and, in
general, by its labor in the supply of its, physical
wants. In the case of vegetables, the strength must
be sufficient to support its weight, and resist those
external disturbances to which it is exposed—such
as the action of winds and other natural effects. : But
what, let us_ask, regulates this necessary quantity
of strength? .. What is the chief resistance which it
has to overcome?... We answer, mainly the weight
of the creature itself. But again; what.is this
weight? It is a force produced by, what? . By the
combined attractions of the whole mass of. matter
composing the globe of the earth, exercised upon
the matter composing the creature itself ; thus the
weight of a man is merely the amount of the attrac: -
tion of the globe of the earth exercised upon the
mattcr composing the body of the man. The amount
of this attractian, therefore, depends upon the quan-
tity of matter in the earth; but not on that alone.
It is a universal law of nature, that the -energy of
the attraction exerted by matter is increased with
the proximity of the attracted body to the centre of
the attracted mass. Se
Now, if the matter composing the globe of the
easth were condensed into half its present bulk, all
bodies placed upon the surface, being proportionally
nearer the centre, would be attracted with greater
energy ; and, on the other hand, if the matter of the
earth were swelled into a larger bulk, the distance
of objects on the surface froin the centre being pro-
portionally inereased, the energy of the attraction
would be diminished. In the one case, the weights
of all bodies would be auginented ; and in the other,
they would be diminished. The weights, then, of
bodies placed on tue surface of ‘the earth, depend
conjointiy on the mass of matter composing the
earth, and on its density, Poe eh ey
It is evident, then, that the adaptation which we
see usually between the strenyth of animals and
plants, and their weights, is, in reality, an exquisite
armony which is maintained between the strength
of these infinitely various tribes of organised crea-
tures, and the mass and density of the globe upon
which they are placed; the slightest disturbance or’
change in this relation would utterly derange the
fitness of things, and would render the globe and
its occupants, whether animal or vegetable, unsuited
to each other. The amount of attraction—or, to.
use the more familiar term—the weight of the body:
on the surface of the globe is, then, an index, so to”
speak, to the organisation of the’ creatures placed’
upon the globe wT ee?
If we would, then, inquire respecting the proba-.
ble organisation of the dwellers upon the plancts, -
_