Before leaving Deepwaters Bay they secured a pail of its water, which they found, on examination, contained a far larger percentage of salt and solid material than the oceans on earth, while a thermometer that they immediately immersed in it soon registered eighty-five degrees Fahrenheit; both of which discoveries confirmed them in what they already knew, namely, that Jupiter had advanced comparatively little from the condition in which the water on the surface is hot, in which state the earth once was.
They were soon beyond the estuary at which they had stopped to study the forms of life and to make this test, and kept on due north for several days, occasionally rising above the air. As their familiarity with their surroundings increased, they made notes of several things. The mountains covered far more territory at their bases than the terrestrial mountains, and they were in places very rugged and showed vast yawning chasms. They were also wooded farther up their sides, and bore but little snow; but so far the travellers had not found them much higher than those on earth, the greatest altitude being the thirty-two thousand feet south of Deepwaters Bay, and one other ridge that was forty thousand; so that, compared with the size of the planet and its continents, they seemed quite small, and the continents themselves were comparatively level. They also noted that spray was blown in vast sheets, till the ocean for miles was white as milk. The wind often attained tornado strength, and the whole surface of the water, about what seemed to be the storm centre, frequently moved with rapidity in the form of foam. Yet, notwithstanding this, the waves were never as large as those to which they were accustomed on earth. This they accounted for very easily by the fact that, while water weighed 2.55 times as much as on earth, the pressure of air was but little more than half as much again, and consequently its effect on all but the very surface of the heavy liquid was comparatively slight.
"Gravity is a useful factor here," observed Cortlandt, as they made a note of this; "for, in addition to giving immunity from waves, it is most effective in checking the elevation of high mountains or table-lands in the high latitudes, which we shall doubtless find sufficiently cool, or even cold, while in tropical regions, which might otherwise be too hot, it interferes with them least, on account of being partly neutralized by the rapid rotation with which all four of the major planets are blessed."
At sunrise the following morning they saw they were approaching another great arm of the sea. It was over a thousand miles wide at its mouth, and, had not the photographs showed the contrary, they would have thought the Callisto had reached the northern end of the continent. It extended into the land fifteen thousand miles, and, on account of the shape of its mouth, they called it Funnel Bay. Rising to a height, they flew across, and came to a great table-land peninsula, with a chain of mountains on either side. The southern range was something over, and the northern something less than, five thousand feet in height, while the table-land between sloped almost imperceptibly towards the middle, in which, as they expected, they found a river compared to which the Mississippi or the Amazon would be but a brook. In honour of the President of the Terrestrial Axis Straightening Company, they called this great projection, which averaged about four thousand miles across by twelve thousand miles long, Bearwarden Peninsula. They already noticed a change in climate; the ferns and palms became fewer, and were succeeded by pines, while the air was also a good deal cooler, which was easily accounted for by their altitude--though even at that height it was considerably denser than at sea-level on earth--and by the fact that they were already near latitude thirty.
The exposed points on the plateau, as also the summits of the first mountains they had seen before alighting, were devoid of vegetation, scarcely so much as a blade of grass being visible. Since they could not account for this by cold, they concluded that the most probable explanation lay in the tremendous hurricanes that, produced by the planet's rapid rotation, frequently swept along its surface, like the earth's trade-winds, but with far more violence. On reaching the northern coast of the peninsula they increased their elevation and changed their course to northeast, not caring to remain long over the great body of water, which they named Cortlandt Bay. The thousands of miles of foam fast flew beneath them, the first thing attracting their attention being a change in the ocean's colour. In the eastern shore of Cortlandt Bay they soon observed the mouth of a river, ten miles across, from which this tinted water issued in a flood. On account of its colour, which reminded them of a stream they knew so well, they christened it the Harlem.
Believing that an expedition up its valley might reveal something of interest, they began the ascent, remaining at an elevation of a few hundred feet. For about three hundred miles they followed this river, which had but few bends, while its sides became more and more precipitous, till it flowed through a cañon four and a half miles across. Though they knew from the wide discoloration of Cortlandt Bay that the volume of water discharged was tremendous, the stream seldom moved at a rate of more than five miles an hour, and for a time was free from rocks and rapids, from which they concluded that it must be very deep. Half an hour later they saw a cloud of steam or mist, which expanded, and almost obscured the sky as they approached. Next they heard a sound like distant thunder, which they took for the prolonged eruption of some giant crater, though they had not expected to find one so far towards the interior of the continent. Presently it became one continuous roar, the echo in the cañon, whose walls were at this place over six hundred feet high, being simply deafening, so that the near discharge of the heaviest artillery would have been completely drowned. "One would think the end of the world was approaching!" shouted Cortlandt through his hands.
"Look!" Bearwarden roared back, "the wind is scattering the mist."
As he spoke, the vapoury curtain was drawn aside, revealing a waterfall of such vast proportions as to dwarf completely anything they had ever seen or even imagined. A somewhat open horseshoe lip, three and a half miles straight across and over four miles following the line of the curve, discharged a sheet of water forty feet thick at the edge into an abyss six hundred feet below. Two islands on the brink divided this sheet of liquid into three nearly equal parts, while myriads of rainbows hovered in the clouds of spray. Two things especially struck the observers: the water made but little curve or sweep on passing over the edge, and then rushed down to the abyss at almost lightning speed, shivering itself to infinitesimal particles on striking any rock or projection at the side. Its behaviour was, of course, due to its weight, and to the fact that on Jupiter bodies fall 40.98 feet the first second, instead of sixteen feet, as on earth, and at correspondingly increasing speed.
Finding that they were being rapidly dazed and stunned by the noise, the travellers caused the Callisto to rise rapidly, and were soon surveying the superb sight from a considerable elevation. Their minds could grasp but slowly the full meaning and titanic power of what they saw, and not even the vast falls in their nearness could make their significance clear. Here was a sheet of water three and a half miles wide, averaging forty feet in depth, moving at a rapid rate towards a sheer fall of six hundred feet. They felt, as they gazed at it, that the power of that waterfall would turn backward every engine and dynamo on the earth, and it seemed as if it might almost put out the fires of the sun. Yet it was but an illustration of the action of the solar orb exerted on a vast area of ocean, the vapour in the form of rain being afterwards turned into these comparatively narrow limits by the topography of the continent. Compared with this, Niagara, with its descent of less than two hundred feet, and its relatively small flow of water, would be but a rivulet, or at best a rapid stream. Reluctantly leaving the fascinating spectacle, they pursued their exploration along the river above the falls. For the first few miles the surface of the water was near that of the land; there were occasional rapids, but few rocks, and the foaming torrent moved at great speed, the red sandstone banks of the river being as polished as though they had been waxed. After a while the obstructions disappeared, but the water continued to rush and surge along at a speed of ten or twelve miles an hour, so that it would be easily navigable only for logs or objects moving in one direction. The surface of the river was soon on an average fifty feet below the edge of the banks, this depression being one result of the water's rapid motion and weight, which facilitated the carving of its channel.
When they had followed up the river about sixty miles towards its source they came upon what at first had the appearance of an ocean. They knew, however, from its elevation, and the flood coming from it, that the water must be fresh, as they soon found 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.