it was。 This lake was about three hundred miles wide； and
stretched from northeast to southwest。 There was rolling land
with hills about its shores； and the foliage on the banks was a
beautiful shade of bluish purple instead of the terrestrial
ubiquitous green。
When near the great lake's upper end； they passed the mouth of a
river on their left side； which； from its volume； they concluded
must be the principal source； and therefore they determined to
trace it。 They found it to be a most beautiful stream； averaging
two and a half miles in width； evidently very deep； and with a
full； steady current。 After proceeding for several hours； they
found that the general placidity grew less； the smooth surface
occasionally became ruffled by projecting rocks and rapids； and
the banks rose till the voyagers again found themselves in a
ravine or canon。
During their sojourn on Jupiter they had had but little
experience with the tremendous winds that they knew； from reason
and observation； must rage in its atmosphere。 They now heard
them whistling over their heads； and； notwithstanding the
protection afforded by the sides of the canon； occasionally
received a gust that made the Callisto swerve。 They kept on
steadily； however； till sunset； at which time it became very dark
on account of the high banks； which rose as steeply as the
Palisades on the Hudson to a height of nearly a thousand feet。
Finding a small island near the eastern bank； they were glad to
secure the Callisto there for the night； below the reach of the
winds； which they； still heard singing loudly but with a musical
note in what seemed to them like the sky。
〃It is incomprehensible to me。〃 said Ayrault； as they sat at
dinner； 〃how the sun； at a distance of four hundred and
eighty…three million miles； can raise the amount of water we have
here passing us； and compared with which the discharge of the
greatest river on earth would be insignificant； to say nothing of
the stream we ascended before reaching this。〃
〃We must remember；〃 replied Cortlandt； 〃that many of the
conditions are different here from those that exist on earth。 We
know that some of the streams are warm； and even hot； and that
the temperature of Deepwaters Bay； and doubtless that of the
ocean also； is considerably higher than ours。 This would
facilitate evaporation。 The density of the atmosphere and the
tremendous winds； of which I suspect we may see more later； must
also help the sun very much in its work of raising vapour。 But
the most potent factor is undoubtedly the vast size of the basin
that these rivers drain。〃
〃The great speed at which the atmospheric currents move；〃 said
Bearwarden； 〃coupled with the comparative lowness of the mountain
chains and the slight obstruction they offer to their passage；
must distribute the rain very thoroughly； notwithstanding the
great unbroken area of the continents。 There can be no such
state of things here as exists in the western part of South
America； where the Andes are so high that any east…bound clouds；
in crossing them； are shoved up so far into a cold region that
all moisture they may have brought from the Pacific is condensed
into rain； with which parts of the western slope are deluged；
while clouds from the Atlantic have come so far they have already
dispersed their moisture； in consequence of which the region just
east of the Andes gets little if any rain。 It is bad for a
continent to have its high mountains near the ocean from which it
should get its rain； and good for it to have them set well back。〃
〃I should not be surprised；〃 said Cortlandt； 〃if we saw another
waterfall to…morrow； though not in the shape of rain。 In the
hour before we stopped we began to see rapids and protruding
rocks。 That means that we are coming to a part of the channel
that is comparatively new； since the older parts have had time to
wear smooth。 I take it； then； that we are near the foot of a
retreating cascade； which we may hope soon to see。 That is
exactly the order in which we found smooth water and rapids in
river No。 1； which we have named the Harlem。〃
After this； not being tired； they used the remaining dark hours
for recording their recent adventures。
CHAPTER XII。
HILLS AND VALLEYS。
With the first light they resumed their journey； and an hour
after setting out they sighted； as Cortlandt had predicted；
another cloud of vapour。 The fallfor such it proved to bewas
more beautiful than the other； for； though the volume of water
was not so great； it fell at one leap； without a break； and at
the same tremendous speed； a distance of more than a thousand
feet。 The canon rang with the echoes； while the spray flew in
sheets against the smooth； glistening； sandstone walls。 Instead
of coming from a river； as the first fall had； this poured at
once from the rocky lip； about two miles across； of a lake that
was eleven hundred feet above the surging mass in the vale below。
〃It is a thousand pities；〃 said Bearwarden； 〃that this cataract
has got so near its source； for； at the rate these streams must
cut； this one in a few hundred years； unless something is done to
prevent it； will have worn back to the lake； and then good…bye to
the falls； which will become a series of rapids。 Perhaps the
first effect will be merely to reduce by a few feet the height of
the falls； in which case they will remain in practically the same
place。〃
About the shores of this lake they saw rhinoceroses with long
thick wool； and herds of creatures that much resembled buffaloes。
〃I do not see；〃 said Bearwarden； 〃why the identical species
should not exist here that till recently； in a geological sense；
inhabited the earth。 The climate and all other conditions are
practically the same on both planets； except a trifling
difference in weight； to which terrestrials would soon adapt
themselves。 We know by spectroscopic analysis that hydrogen；
iron； magnesium； and all our best…known substances exist in the
sun； and even the stars； while the earth contains everything we
have found in meteorites。 Then why make an exception of life；
instead of supposing that at corresponding periods of development
the same living forms inhabit all？ It would be assuming the
eternal sterilization of the functions of Nature to suppose that
our earth is the only body that can produce them。〃
〃The world of organic life is so much more complex；〃 replied
Cortlandt； 〃than that of the crystal； that it requires great
continuity。 So far we certainly have seen no men； or anything
like them； not even so much as a monkey； though I suppose；
according to your reasoning； Jupiter has not advanced far enough
to produce even that。〃
〃Exactly；〃 replied Bearwarden； 〃for it will require vast periods；
and； according to my belief； at least half the earth's time of
habitability had passed before man appeared。 But we see Jupiter
is admirably suited for those who have been developed somewhere
else； and it would be an awful shame if we allowed it to lie
unimproved till it produces appreciative inhabitants of its own；
for we find more to admire in one half…hour than its entire
present population during its lifetime。 Yet； how magnificent
this world is； and how superior in its natural state to ours！
The mountainous horns of these crescent…shaped continents protect
them and the ocean they enclose from the cold polar marine
currents； and in a measure from the icy winds； while the elevated
country on the horns near the equator might be a Garden of Eden；
or ideal resort。 To be sure； the continents might support a
larger population； if more broken up； notwithstanding the
advantage resulting from the comparatively low mountains along
the coasts； and the useful winds。 A greater subdivision of land
and water； more great islands connected by isthmuses； and more
mediterraneans joined by straits； would be a further advantage to
commerce； but with the sources of power at hand； the resistless
winds and water…power； much increased in effectiveness by their
weight； the great tides when several moons are on the same side；
or opposite the sun； internal heat near the surface； and abundant
coal…supply doubtless already formed and also near the surface；
such small alterations could be made very easily； and would serve
merely to prevent our becoming rusty。
〃As Jupiter's distance from the sun varies from 506；563；000 miles
at aphelion to only 460；013；000 at perihelion； this difference；
in connection with even the slight inclination of the axis； must
make a slight change in seasons； but as the inclination is
practically nothing； almost the entire change results from the
difference in distance。 This means that the rise or fall in
temperature is general on every degree of latitude； all being
warmed simultaneously； more or less； as the planet approaches or
departs from the sun。 It means also that about the same
conditions that Secretary Deepwaters suggested as desirable for
the earth； prevail here； and that Jupiter represents； therefore；
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