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about the acme of climate naturally provided。 On account of its
rapid rotation and vast size; the winds have a tornado's
strength; but they are nothing at this distance from the sun to
what they would be if a planet with its present rate of rotation
and size were where Venus or even the earth is。 In either of
these positions no land life with which we are acquainted could
live on the surface; for the slope of the atmospheric isobarsi。
e。; the lines of equal barometric pressure that produce wind by
becoming tilted through unequal expansion; after which the air;
as it were; flows down…hillwould be too great。 The ascending
currents about the equator would also; of course; be vastly
strengthened; so that we see a wise dispensation of Providence in
placing the large planets; which also rotate so rapidly; at a
great distance from the sun; which is the father of all winds;
rotation alone; however rapid; being unable to produce them。〃
They found this lake was about six times the size of Lake
Superior; and that several large and small streams ran into its
upper end。 These had their sources in smaller lakes that were at
slightly higher elevations。 Though the air was cool; the sun
shone brightly; while the ground was covered with flowers
resembling those of the northern climes on earth; of all shapes
and lines。 Twice a day these sent up their song; and trees were
covered with buds; and the birds twittered gaily。 The streams
murmured and bubbled; and all things reminded the travellers of
early morning in spring。
〃If anything could reconcile me;〃 said Bearwarden; 〃to exchange
my active utilitarian life for a rustic poetical existence; it
would be this place; for it is far more beautiful than anything I
have seen on earth。 It needs but a Maud Muller and a few cows to
complete the picture; since Nature gives us a vision of eternal
peace and repose。〃
Somehow the mention of Maud Muller; and the delicate and refined
flowers; whose perfume he inhaled; brought up thoughts that were
never far below the surface in Ayrault's mind。 〃The place is
heavenly enough;〃 said he; 〃to make one wish to live and remain
here forever; but to me it would be Hamlet with Hamlet left out。〃
〃Ah! poor chap;〃 said Cortlandt; 〃you are in love; but you are
not to be pitied; for though the thrusts at the heart are sharp;
they may be the sweetest that mortals know。〃
The following morning they reluctantly left the picturesque
shores of Lake Serenity; with their beautiful tints and foliage;
and resumed the journey; to explore a number of islands in the
ocean in the west; which were recorded on their negatives。
Ascending to rarefied air; they saw great chains of mountains;
which they imagined ran parallel to the coast; rising to
considerable altitudes in the east。 The tops of all glistened
with a mantle of snow in the sunlight; while between the ridges
they saw darker and evidently fertile valleys。 They passed;
moving northwest; over large and small lakes; all evidently part
of the same great system; and continued to sweep along for
several days with a beautiful panorama; as varying as a
kaleidoscope; spread beneath their eyes。 They observed that the
character of the country gradually changed。 The symmetrically
rounded mountains and hills began to show angles; while great
slabs of rock were split from the faces。 The sides also became
less vertical; and there was an accumulation of detrital
fragments about their bases。 These heaps of fractured stone had
in some cases begun to disintegrate and form soil; on which there
was a scant growth of vegetation; but the sides and summits;
whose jaggedness increased with their height; were absolutely
bare。
〃Here;〃 said Cortlandt; 〃we have unmistakable evidence of frost
and ice action。 The next interesting question is; How recently
has denudation occurred? The absence of plant life at the
exposed places;〃 he continued; as if lecturing to a class; 〃can
be accounted for here; as nearer the equator; by the violence of
the wind; but I greatly doubt whether water will now freeze in
this latitude at any season of the year; for; even should the
Northern hemisphere's very insignificant winter coincide with the
planet's aphelion; the necessary drop from the present
temperature would be too great to be at all probable。 If; then;
it is granted that ice does not form here now; notwithstanding
the fact that it has done so; the most plausible conclusion is
that the inclination of Jupiter's axis is automatically changing;
as we know the earth's has often done。 There being nothing
incompatible in this view with the evidence at hand; we can
safely assume it correct for the time being at least。 When
farther south; you remember; we found no trace of ice action;
notwithstanding the comparative slowness with which we decided
that the ridges in the crust had been upheaved on account of the
resisting power of gravity; and; as I see now; also on account of
Jupiter's great mass; which must prevent its losing its heat
anything like as fast as the earth has; in which I think also we
have the explanation of the comparatively low elevation of the
mountains that we found we could not account for by the power of
gravitation alone。'2' From the fact that the exposed surface
farther south must be old; on account of the slow upheaval and
the slight wear to which it is exposed; about the only wearing
agent being the wind; which would be powerless to erase
ice…scratches; especially since; on account of gravity's power;
it cannot; like our desert winds; carry much sandwhich; as we
know; has cut away the base of the SphinxI think it is logical
to conclude that; though Jupiter's axis is changing naturally as
the earth's has been; it has never varied as much as twenty…three
and a half degrees; and certainly to nothing like the extent to
which we see Venus and Uranus tilted to…day。〃
'2' It is well known that mountain chains are but ridges or
foldings in the crust upheaved as the interior cools and shrinks。
This is proved by reason and by experiments with viscous clay or
other material placed upon a sheet of stretched rubber; which is
afterwards allowed to contract; whereupon the analogues of
mountain ridges are thrown up。
〃I follow you;〃 said Bearwarden; 〃and do not see how we could
arrive at anything else。 From Jupiter's low specific gravity;
weighing but little more than an equal bulk of water; I should
say the interior must be very hot; or else is composed of light
material; for the crust's surface; or the part we see; is
evidently about as dense as what we have on earth。 These things
have puzzled me a good deal; and I have been wondering if Jupiter
may not have been formed before the earth and the smaller
planets。〃
〃The discrepancies between even the best authorities;〃 replied
Cortlandt; 〃show that as yet but little has been discovered from
the earth concerning Jupiter's real condition。 The two theories
that try to account for its genesis are the ring theory and the
nebulous。 We know that the sun is constantly emitting vast
volumes of heat and light; and that; with the exception of the
heat resulting from the impact of falling meteors; it receives
none from outside; the principal source being the tremendous
friction and pressure between the cooling and shrinking strata
within the great mass of the sun itself。 A seeming paradox
therefore comes in here; which must be considered: If the sun
were composed entirely of gas; it would for a time continue to
grow hotter; but the sun is incessantly radiating light and heat;
and consequently becoming smaller。 Therefore the farther back we
go the hotter we find the sun; and also the larger; till; instead
of having a diameter of eight hundred and eighty thousand miles;
it filled the space now occupied by the entire solar system。
Here is where the two theories start。 According to the first;
the revolving nebulous mass threw off a ring that became the
planet Neptune; afterwards another that contained the material
for Uranus; and so on; the lightest substance in the sun being
thrown off first; by which they accounted for the lightness of
the four great planets; and finally Mars; the earth; and the
small dense planets near the sun。 The advocates of this theory
pointed to Saturn's rings as an illustration of the birth of a
planet; or; rather; in that case a satellite。 According to this;
the major planets have had a far longer separate existence than
the minor; which would account for their being so advanced
notwithstanding their size。 This theory may again come into
general acceptance; but for the present it has been discredited
by the nebulous。 According to this second theory; at the time
the sun filled all the space inside of Neptune's; orbit; or
extended even farther; several centres of condensation were
formed within the nebulous; gaseous mass。 The greatest centre
became the sun; and the others; large and small; the planets;
whichas a result of the spiral motion of the whole; such as is
now going on before our eyes in the great nebulae of fifty… one
M。 Canuin venaticorum; and many othersbegan to revolve about
the greatest central