Four days later, after crossing a ridge of mountains that the pressure on the aneroid barometer showed to be about thirty-two thousand feet high, and a stretch of flat country a few miles in width, they came to a great arm of the sea. It was about thirty miles wide at its mouth, which was narrowed like the neck of a bottle, and farther inland was over one hundred miles across, and though their glasses, the clear air, and the planet's size enabled them to see nearly five hundred miles, they could not find its end. In the shallow water along its shores, and on the islands rising but a few feet above the waves, they saw all kinds of amphibians and sea-monsters. Many of these were almost the exact reproduction in life of the giant plesiosaurs, dinosaurs, and elasmosaurs, whose remains are preserved in the museums on earth. The reptilian bodies of the elasmosaurs, seventy-five feet in length, with the forked tongues, distended jaws and fangs of a snake, were easily taken for the often described but probably mythical sea- serpent, as partially coiled they occasionally raised their heads twelve or fifteen feet.

"Man in his natural state," said Cortlandt, "would have but small chance of surviving long among such neighbours. Buckland, I think, once indulged in the jeu d'esprit of supposing an ichthyosaur lecturing on the human skull. 'You will at once perceive,' said the lecturer, 'that the skull before us belonged to one of the lower order of animals. The teeth are very insignificant, the power of the jaws trifling, and altogether it seems wonderful how the creature could have procured food.' Armed with modern weapons, and in this machine, we are, of course, superior to the most powerful monster; but it is not likely that, had man been so surrounded during the whole of his evolution, he could have reached his present plane."

Notwithstanding the striking similarity of these creatures to their terrestrial counterparts that existed on earth during its corresponding period, there were some interesting modifications. The organs of locomotion in the amphibians were more developed, while the eyes of all were larger, the former being of course necessitated by the power of gravity, and the latter by the greater distance from the sun.

"The adaptability and economy of Nature," said Cortlandt, "have always amazed me. In the total blackness of the Kentucky Mammoth Cave, where eyes would be of no use to the fishes, our common mother has given them none; while if there is any light, though not as much as we are accustomed to, she may be depended upon to rise to the occasion by increasing the size of the pupil and the power of the eye. In the development of the ambulatory muscles we again see her handiwork, probably brought about through the 'survival of the fittest.' The fishes and those wholly immersed need no increase in power, for, though they weigh more than they would on earth, the weight of the water they displace is increased at the same rate also, and their buoyancy remains unchanged. If the development of life here so closely follows its lines on earth, with the exception of comparatively slight modifications, which are exactly what, had we stopped to think, we should have expected to find, may we not reasonably ask whether she will not continue on these lines, and in time produce beings like ourselves, but with more powerful muscles and eyes capable of seeing clearly with less light? Reasoning by analogy, we can come to no other conclusion, unless their advent is anticipated by the arrival of ready-made colonists from the more advanced earth, like ourselves. In that case man, by pursuing the same destructive methods that he has pursued in regard to many other species, may exterminate the intervening links, and so arrest evolution."

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.