"Let us hear the explanation," said the Captain.
"They become invisible when the trees lose their leaves, and they reappear when they resume them."
"His explanation is not without ingenuity," observed Barbican to M"Nicholl, "but, my dear friend," turning to Ardan, "it is hardly admissible."
"Probably not," said Ardan, "but why not?"
"Because as the Sun is nearly always vertical to the lunar equator, the Moon can have no change of seasons worth mentioning; therefore her vegetation can present none of the phenomena that you speak of."
This was perfectly true. The slight obliquity of the Moon"s axis, only 1-1/2, keeps the Sun in the same alt.i.tude the whole year around. In the equatorial regions he is always vertical, and in the polar he is never higher than the horizon. Therefore, there can be no change of seasons; according to the lat.i.tude, it is a perpetual winter, spring, summer, or autumn the whole year round. This state of things is almost precisely similar to that which prevails in Jupiter, who also stands nearly upright in his...o...b..t, the inclination of his axis being only about 3.
But how to account for the _grooves_? A very hard nut to crack. They must certainly be a later formation than the craters and the rings, for they are often found breaking right through the circular ramparts.
Probably the latest of all lunar features, the results of the last geological epochs, they are due altogether to expansion or shrinkage acting on a large scale and brought about by the great forces of nature, operating after a manner altogether unknown on our earth. Such at least was Barbican"s idea.
"My friends," he quietly observed, "without meaning to put forward any pretentious claims to originality, but by simply turning to account some advantages that have never before befallen contemplative mortal eye, why not construct a little hypothesis of our own regarding the nature of these grooves and the causes that gave them birth? Look at that great chasm just below us, somewhat to the right. It is at least fifty or sixty miles long and runs along the base of the _Apennines_ in a line almost perfectly straight. Does not its parallelism with the mountain chain suggest a causative relation? See that other mighty _rill_, at least a hundred and fifty miles long, starting directly north of it and pursuing so true a course that it cleaves _Archimedes_ almost cleanly into two. The nearer it lies to the mountain, as you perceive, the greater its width; as it recedes in either direction it grows narrower.
Does not everything point out to one great cause of their origin? They are simple creva.s.ses, like those so often noticed on Alpine glaciers, only that these tremendous cracks in the surface are produced by the shrinkage of the crust consequent on cooling. Can we point out some a.n.a.logies to this on the Earth? Certainly. The defile of the Jordan, terminating in the awful depression of the Dead Sea, no doubt occurs to you on the moment. But the _Yosemite Valley_, as I saw it ten years ago, is an apter comparison. There I stood on the brink of a tremendous chasm with perpendicular walls, a mile in width, a mile in depth and eight miles in length. Judge if I was astounded! But how should we feel it, when travelling on the lunar surface, we should suddenly find ourselves on the brink of a yawning chasm two miles wide, fifty miles long, and so fathomless in sheer vertical depth as to leave its black profundities absolutely invisible in spite of the dazzling sunlight!"
"I feel my flesh already crawling even in the antic.i.p.ation!" cried Ardan.
"I shan"t regret it much if we never get to the Moon," growled M"Nicholl; "I never hankered after it anyhow!"
By this time the Projectile had reached the fortieth degree of lunar lat.i.tude, and could hardly be further than five hundred miles from the surface, a distance reduced to about 5 miles by the travellers" gla.s.ses.
Away to their left appeared _Helicon_, a ring mountain about 1600 feet high; and still further to the left the eye could catch a glimpse of the cliffs enclosing a semi-elliptical portion of _Mare Imbrium_, called the _Sinus Iridium_, or Bay of the Rainbows.
In order to allow astronomers to make complete observations on the lunar surface, the terrestrial atmosphere should possess a transparency seventy times greater than its present power of transmission. But in the void through which the Projectile was now floating, no fluid whatever interposed between the eye of the observer and the object observed.
Besides, the travellers now found themselves at a distance that had never before been reached by the most powerful telescopes, including even Lord Rosse"s and the great instrument on the Rocky Mountains.
Barbican was therefore in a condition singularly favorable to resolve the great question concerning the Moon"s inhabitableness. Nevertheless, the solution still escaped him. He could discover nothing around him but a dreary waste of immense plains, and towards the north, beneath him, bare mountains of the aridest character.
Not the slightest vestige of man"s work could be detected over the vast expanse. Not the slightest sign of a ruin spoke of his ever having been there. Nothing betrayed the slightest trace of the development of animal life, even in an inferior degree. No movement. Not the least glimpse of vegetation. Of the three great kingdoms that hold dominion on the surface of the globe, the mineral, the vegetable and the animal, one alone was represented on the lunar sphere: the mineral, the whole mineral, and nothing but the mineral.
"Why!" exclaimed Ardan, with a disconcerted look, after a long and searching examination, "I can"t find anybody. Everything is as motionless as a street in Pompeii at 4 o"clock in the morning!"
[Ill.u.s.tration: THE SOLUTION STILL ESCAPED HIM.]
"Good comparison, friend Ardan;" observed M"Nicholl. "Lava, slag, volcanic eminences, vitreous matter glistening like ice, piles of scoria, pitch black shadows, dazzling streaks, like rivers of light breaking over jagged rocks--these are now beneath my eye--these alone I can detect--not a man--not an animal--not a tree. The great American Desert is a land of milk and honey in comparison with the joyless...o...b..over which we are now moving. However, even yet we can predicate nothing positive. The atmosphere may have taken refuge in the depths of the chasms, in the interior of the craters, or even on the opposite side of the Moon, for all we know!"
"Still we must remember," observed Barbican, "that even the sharpest eye cannot detect a man at a distance greater than four miles and a-half, and our gla.s.ses have not yet brought us nearer than five."
"Which means to say," observed Ardan, "that though we can"t see the Selenites, they can see our Projectile!"
But matters had not improved much when, towards four o"clock in the morning, the travellers found themselves on the 50th parallel, and at a distance of only about 375 miles from the lunar surface. Still no trace of the least movement, or even of the lowest form of life.
"What peaked mountain is that which we have just pa.s.sed on our right?"
asked Ardan. "It is quite remarkable, standing as it does in almost solitary grandeur in the barren plain."
"That is _Pico_," answered Barbican. "It is at least 8000 feet high and is well known to terrestrial astronomers as well by its peculiar shadow as on account of its comparative isolation. See the collection of perfectly formed little craters nestling around its base."
"Barbican," asked M"Nicholl suddenly, "what peak is that which lies almost directly south of _Pico_? I see it plainly, but I can"t find it on my map."
"I have remarked that pyramidal peak myself," replied Barbican; "but I can a.s.sure you that so far it has received no name as yet, although it is likely enough to have been distinguished by the terrestrial astronomers. It can"t be less than 4000 feet in height."
"I propose we called it _Barbican_!" cried Ardan enthusiastically.
"Agreed!" answered M"Nicholl, "unless we can find a higher one."
"We must be before-hand with Schmidt of Athens!" exclaimed Ardan. "He will leave nothing unnamed that his telescope can catch a glimpse of."
"Pa.s.sed unanimously!" cried M"Nicholl.
"And officially recorded!" added the Frenchman, making the proper entry on his map.
"_Salve, Mt. Barbican!_" then cried both gentlemen, rising and taking off their hats respectfully to the distant peak.
"Look to the west!" interrupted Barbican, watching, as usual, while his companions were talking, and probably perfectly unconscious of what they were saying; "directly to the west! Now tell me what you see!"
"I see a vast valley!" answered M"Nicholl.
"Straight as an arrow!" added Ardan.
"Running through lofty mountains!" cried M"Nicholl.
"Cut through with a pair of saws and scooped out with a chisel!" cried Ardan.
"See the shadows of those peaks!" cried M"Nicholl catching fire at the sight. "Black, long, and sharp as if cast by cathedral spires!"
"Oh! ye crags and peaks!" burst forth Ardan; "how I should like to catch even a faint echo of the chorus you could chant, if a wild storm roared over your beetling summits! The pine forests of Norwegian mountains howling in midwinter would not be an accordeon in comparison!"
"Wonderful instance of subsidence on a grand scale!" exclaimed the Captain, hastily relapsing into science.
"Not at all!" cried the Frenchman, still true to his colors; "no subsidence there! A comet simply came too close and left its mark as it flew past."
"Fanciful exclamations, dear friends," observed Barbican; "but I"m not surprised at your excitement. Yonder is the famous _Valley of the Alps_, a standing enigma to all selenographers. How it could have been formed, no one can tell. Even wilder guesses than yours, Ardan, have been hazarded on the subject. All we can state positively at present regarding this wonderful formation, is what I have just recorded in my note-book: the _Valley of the Alps_ is about 5 mile wide and 70 or 80 long: it is remarkably flat and free from _debris_, though the mountains on each side rise like walls to the height of at least 10,000 feet.--Over the whole surface of our Earth I know of no natural phenomenon that can be at all compared with it."
"Another wonder almost in front of us!" cried Ardan. "I see a vast lake black as pitch and round as a crater; it is surrounded by such lofty mountains that their shadows reach clear across, rendering the interior quite invisible!"
"That"s _Plato_;" said M"Nicholl; "I know it well; it"s the darkest spot on the Moon: many a night I gazed at it from my little observatory in Broad Street, Philadelphia."
"Right, Captain," said Barbican; "the crater _Plato_, is, indeed, generally considered the blackest spot on the Moon, but I am inclined to consider the spots _Grimaldi_ and _Riccioli_ on the extreme eastern edge to be somewhat darker. If you take my gla.s.s, Ardan, which is of somewhat greater power than yours, you will distinctly see the bottom of the crater. The reflective power of its plateau probably proceeds from the exceedingly great number of small craters that you can detect there."
"I think I see something like them now," said Ardan. "But I am sorry the Projectile"s course will not give us a vertical view."
"Can"t be helped!" said Barbican; "we must go where it takes us. The day may come when man can steer the projectile or the balloon in which he is shut up, in any way he pleases, but that day has not come yet!"
Towards five in the morning, the northern limit of _Mare Imbrium_ was finally pa.s.sed, and _Mare Frigoris_ spread its frost-colored plains far to the right and left. On the east the travellers could easily see the ring-mountain _Condamine_, about 4000 feet high, while a little ahead on the right they could plainly distinguish _Fontenelle_ with an alt.i.tude nearly twice as great. _Mare Frigoris_ was soon pa.s.sed, and the whole lunar surface beneath the travellers, as far as they could see in all directions, now bristled with mountains, crags, and peaks. Indeed, at the 70th parallel the "Seas" or plains seem to have come to an end.
The spy-gla.s.ses now brought the surface to within about three miles, a distance less than that between the hotel at Chamouni and the summit of Mont Blanc. To the left, they had no difficulty in distinguishing the ramparts of _Philolaus_, about 12,000 feet high, but though the crater had a diameter of nearly thirty miles, the black shadows prevented the slightest sign of its interior from being seen. The Sun was now sinking very low, and the illuminated surface of the Moon was reduced to a narrow rim.
By this time, too, the bird"s eye view to which the observations had so far princ.i.p.ally confined, decidedly altered its character. They could now look back at the lunar mountains that they had been just sailing over--a view somewhat like that enjoyed by a tourist standing on the summit of Mt. St. Gothard as he sees the sun setting behind the peaks of the Bernese Oberland. The lunar landscapes however, though seen under these new and ever varying conditions, "hardly gained much by the change," according to Ardan"s expression. On the contrary, they looked, if possible, more dreary and inhospitable than before.