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."