Changing Landscapes

: LAST OF EARTH

On reaching the Callisto, Ayrault worked the lock he had had

placed on the lower door, which, to avoid carrying a key, was

opened by a combination. The car's interior was exactly as they

had left it, and they were glad to be in it again.



"Now," said Bearwarden, "we can have a sound and

undisturbed sleep, which is what I want more than

anything else. No prowlers can trouble us here, and we

shall not need the protection-wires."



They then opened a window in each side--for the large glass

plates, admitting the sun when closed, made the Callisto rather

warm--and placed a stout wire netting within them to keep out

birds and bats, and then, though it was but little past noon, got

into their comfortable beds and slept nine hours at a stretch.

Their strong metal house was securely at rest, receiving the

sunlight and shedding the rain and dew as it might have done on

earth. No winds or storms, lightnings or floods, could trouble

it, while the multiformed monsters of antiquity and mythology

restored in life, with which the terrestrials had been thrown

into such close contact, roamed about its polished walls. Not

even the fiercest could affect them, and they would but see

themselves reflected in any vain assaults. The domed symmetrical

cylinder stood there as a monument to human ingenuity and skill,

and the travellers' last thought as they fell asleep was, "Man is

really lord of creation."



The following day at about noon they awoke, and had a bath in the

warm pool. They saw the armoured mass of the great ant evidently

undisturbed, while the bodies of its victims were already shining

skeletons, and raised a small cairn of stones in memory of the

struggle they had had there.



"We should name this place Kentucky," said Bearwarden, "for it is

indeed a dark and bloody ground," and, seeing the aptness of the

appellation, they entered it so on their charts. While Ayrault

got the batteries in shape for resuming work. Bearwarden

prepared a substantial breakfast. This consisted of oatmeal and

cream kept hermetically sealed in glass, a dish of roast grouse,

coffee, pilot bread, a bottle of Sauterne, and another of Rhine

wine.



"This is the last meal we shall take hereabouts," said their

cook, as they plied their knives and forks beneath the trees, "so

here is a toast to our adventures, and to all the game we have

killed." They drained their glasses in drinking this, after

which Bearwarden regaled them with the latest concert-hall song

which he had at his tongue's end.



About an hour before dark they re-entered their projectile, and,

as a mark of respect to their little ship, named the great branch

of the continent on which they had alighted Callisto Point. They

then got under way. The batteries had to develop almost their

maximum power to overcome Jupiter's attraction; but they were

equal to the task, and the Callisto was soon in the air.

Directing their apergy to the mountains towards the interior of

the continent, and applying repulsion to any ridge or hill over

which they passed, thereby easing the work of the batteries

engaged in supporting the Callisto, they were soon sweeping along

at seventy-five to one hundred miles an hour. By keeping the

projectile just strongly enough charged to neutralize

gravitation, they remained for the most part within two hundred

feet of the ground, seldom rising to an altitude of more than a

mile, and were therefore able to keep the windows at the sides

open and so obtain an unobstructed view. If, however, at any

time they felt oppressed by Jupiter's high barometric pressure,

and preferred the terrestrial conditions, they had but to rise

till the barometer fell to thirty. Then, if an object of

interest recalled them to sea-level, they could keep the

Callisto's inside pressure at what they found on the Jovian

mountains, by screwing up the windows. On account of the

distance of sixty-four thousand miles from Jupiter's equator to

the pole, they calculated that going at the speed of a hundred

miles an hour, night and day, it would take them twenty-five

terrestrial days to reach the pole even from latitude two degrees

at which they started. But they knew that, if pressed for time,

they could rise above the limits of the atmosphere, and move with

planetary speed; while, if they wished a still easier method of

pursuing their observation, they had but to remain poised between

the sun and Jupiter, beyond the latter's upper air, and

photograph or map it as it revolved before them.



By sunset they had gone a hundred miles. Wishing to push along,

they closed the windows, rose higher to avoid any mountain-tops

that might be invisible in the moonlight, and increased their

speed. The air made a gentle humming sound as they shot through

it, and towards morning they saw several bright points of light

in which they recognized, by the aid of their glasses, sheets of

flame and torrents of molten glowing lava, bursting at intervals

or pouring steadily from several volcanoes. From this they

concluded they were again near an ocean, since volcanoes need the

presence of a large body of water to provide steam for their

eruptions.



With the rising sun they found the scene of the day before

entirely changed. They were over the shore of a vast ocean that

extended to the left as far as they could see, for the range of

vision often exceeded the power of sight. The coast-line ran

almost due north and south, while the volcanoes that dotted it,

and that had been luminous during the night, now revealed their

nature only by lines of smoke and vapours. They were struck by

the boldness and abruptness of the scenery. The mountains and

cliffs had been but little cut down by water and frost action,

and seemed in the full vigour of their youth, which was what the

travellers had a right to expect on a globe that was still

cooling and shrinking, and consequently throwing up ridges in the

shape of mountains far more rapidly than a planet as matured and

quiescent as the earth. The absence of lakes also showed them

that there had been no Glacial period, in the latitudes they were

crossing, for a very long time.



"We can account for the absence of ice-action and scratches,"

said Cortlandt, "in one of two ways. Either the proximity of the

internal heat to the surface prevents water from freezing in all

latitudes, or Jupiter's axis has always been very nearly

perpendicular to its orbit, and consequently the thermometer has

never been much below thirty-two degrees Fahrenheit; for, at the

considerable distance we are now from the sun, it is easy to

conceive that, with the axis much inclined, there might be cold

weather, during the Northern hemisphere's winter, that would last

for about six of our years, even as near the equator as this.

The substantiation of an ice-cap at the pole will disprove the

first hypothesis; for what we took for ice before alighting may

have been but banks of cloud, since, having been in the plane of

the planet's equator at the time, we had naturally but a very

oblique view of the poles; while the absence of glacial scratches

shows, I take it, that though the axis may have been a good deal

more inclined than at present, it has not, at all events since

Jupiter's Palaeozoic period, been as much so as that of Uranus or

Venus. The land on Jupiter, corresponding to the Laurentian

Hills on earth, must even here have appeared at so remote a

period that the first surface it showed must long since have been

worn away, and therefore any impressions it received have also

been erased.



"Comparing this land with the photographs we took from space, I

should say it is the eastern of the two crescent-shaped

continents we found apparently facing each other. Their present

form I take to be only the skeleton outline of what they will be

at the next period of Jupiter's development. They will, I

predict, become more like half moons than crescents, though the

profile may be much indented by gulfs and bays, their superficial

area being greatly increased, and the intervening ocean

correspondingly narrowed. We know that North America had a very

different shape during the Cretaceous or even the Middle Tertiary

period from what it has now, and that the Gulf of Mexico extended

up the valley of the Mississippi as far as the Ohio, by the

presence of a great coral reef in the Ohio River near Cincinnati.

We know also that Florida and the Southeastern Atlantic States

are a very recent addition to the continent, while the pampas of

the Argentine Republic have, in a geological sense, but just been

upheaved from the sea, by the fact that the rivers are all on the

surface, not having had time to cut down their channels below the

surrounding country. By similar reasoning, we know that the

canon of the Colorado is a very old region, though the

precipitateness of its banks is due to the absence of rain, for a

local water-supply would cut back the banks, having most effect

where they were steepest, since at those points it would move

with the greatest speed. Thus the majestic canon owes its

existence to two things: the length of time the river has been at

work, and the fact that the water flowing through it comes from

another region where, of course, there is rain, and that it is

merely in transit, and so affects only the bed on which it moves.

Granting that this is the eastern of the two continents we

observed, it evidently corresponds more in shape to the Eastern

hemisphere on earth than to the New World, both of which are set

facing one another, since both drain towards the Atlantic Ocean.

But the analogy here holds also, for the past outlines of the

Eastern hemisphere differed radically from what they are now.

The Mediterranean Sea was formerly of far greater extent than we

see it to-day, and covered nearly the whole of northern Africa

and the old upheaved sea-bottom that we see in the Desert of

Sahara. Much of this great desert, as we know, has a

considerable elevation, though part of it is still below the

level of the Mediterranean.



"Perhaps a more striking proof of this than are the remains of

fishes and marine life that are found there, is the dearth of

natural harbours and indentations in Africa's northern coast,

while just opposite, in southern Europe, there are any number;

which shows that not enough time has elapsed since Africa's

upheaval for liquid or congealed water to produce them. Many of

Europe's best harbours, and Boston's, in our country, have been

dug out by slow ice-action in the oft-recurring Glacial periods.

The Black and Caspian Seas were larger than we now find them;

while the Adriatic extended much farther into the continent,

covering most of the country now in the valley of the Po. In

Europe the land has, of course, risen also, but so slowly that

the rivers have been able to keep their channels cut down; proof

of their ability to perform which feat we see when an ancient

river passes through a ridge of hills or mountains. The river

had doubtless been there long before the mountains began to rise,

but their elevation was so gradual that the rate of the river's

cutting down equalled or exceeded their coming up; proof of which

we have in the patent fact that the ancient river's course

remains unchanged, and is at right angles to the mountain chain.

From all of which we see that the Eastern hemisphere's crescent

hollow--of which, I take it, the Mediterranean, Black, and

Caspian Sea depressions are the remains--has been gradually

filled in, by the elevation of the sea's bottom, and the

extension of deltas from the detrital matter brought from the

high interior of the continents by the rivers, or by the combined

action of the two. Now, since the Gulf of Mexico has been

constantly growing smaller, and the Mediterranean is being

invaded by the land, I reason that similar causes will produce

like effects here, and give to each continent an area far greater

than our entire globe. The stormy ocean we behold in the west,

which corresponds to our Atlantic, though it is far more of a

mare clausum in the geographical sense, is also destined to

become a calm and placid inland sea. There are, of course,

modifications of and checks to the laws tending to increase the

land area. England was formerly joined to the continent, the

land connecting the two having been rather washed away by the

waves and great tides than by any sinking of the English

Channel's bottom, the whole of which is comparatively shallow.

Another case of this kind is seen in Cape Cod and the islands of

Martha's Vineyard and Nantucket, all of which are washing away so

rapidly that they would probably disappear before the next

Glacial period, were we not engaged in preventing its recurrence.

These detached islands and sand-bars once formed one large

island, which at a still earlier time undoubtedly was joined to

the mainland. The sands forming the detached masses are in a

great processional march towards the equator, but it is the

result simply of winds and waves, there being no indication of

subsidence. Along the coast of New Jersey we see denudation and

sinking going on together, the well-known SUNKEN FOREST being an

instance of the latter. The border of the continent proper also

extends many miles under the ocean before reaching the edge of

the Atlantic basin. Volcanic eruptions sometimes demolish parts

of headlands and islands, though these recompense us in the

amount of material brought to the surface, and in the increased

distance they enable water to penetrate by relieving the interior

of part of its heat, for any land they may destroy."



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