All Around the Moon Part 22

"The _Apennines_," answered Barbican; "and those on the left are the _Carpathians_."

"I have seen very few mountain chains or ranges in the Moon," remarked Ardan, after some minutes' observation.

"Mountains chains are not numerous in the Moon," replied Barbican, "and in that respect her oreographic system presents a decided contrast with that of the Earth. With us the ranges are many, the craters few; in the Moon the ranges are few and the craters innumerable."

Barbican might have spoken of another curious feature regarding the mountain ranges: namely, that they are chiefly confined to the northern hemisphere, where the craters are fewest and the "seas" the most extensive.

For the benefit of those interested, and to be done at once with this part of the subject, we give in the following little table a list of the chief lunar mountain chains, with their lat.i.tude, and respective heights in English feet.

_Name._ _Degrees of Lat.i.tude._ _Height._

{ _Altai Mountains_ 17 to 28 13,000ft.

Southern { _Cordilleras_ 10 to 20 12,000 Hemisphere. { _Pyrenees_ 8 to 18 12,000 { _Riphean_ 5 to 10 2,600

{ _Haemus_ 10 to 20 6,300 { _Carpathian_ 15 to 19 6,000 { _Apennines_ 14 to 27 18,000 Northern { _Taurus_ 25 to 34 8,500 Hemisphere. { _Hercynian_ 17 to 29 3,400 { _Caucasus_ 33 to 40 17,000 { _Alps_ 42 to 30 10,000

Of these different chains, the most important is that of the _Apennines_, about 450 miles long, a length, however, far inferior to that of many of the great mountain ranges of our globe. They skirt the western sh.o.r.es of the _Mare Imbrium_, over which they rise in immense cliffs, 18 or 20 thousand feet in height, steep as a wall and casting over the plain intensely black shadows at least 90 miles long. Of Mt.

_Huyghens_, the highest in the group, the travellers were just barely able to distinguish the sharp angular summit in the far west. To the east, however, the _Carpathians_, extending from the 18th to 30th degrees of east longitude, lay directly under their eyes and could be examined in all the peculiarities of their distribution.

Barbican proposed a hypothesis regarding the formation of those mountains, which his companions thought at least as good as any other.

Looking carefully over the _Carpathians_ and catching occasional glimpses of semi-circular formations and half domes, he concluded that the chain must have formerly been a succession of vast craters. Then had come some mighty internal discharge, or rather the subsidence to which _Mare Imbrium_ is due, for it immediately broke off or swallowed up one half of those mountains, leaving the other half steep as a wall on one side and sloping gently on the other to the level of the surrounding plains. The _Carpathians_ were therefore pretty nearly in the same condition as the crater mountains _Ptolemy_, _Alpetragius_ and _Arzachel_ would find themselves in, if some terrible cataclysm, by tearing away their eastern ramparts, had turned them into a chain of mountains whose towering cliffs would nod threateningly over the western sh.o.r.es of _Mare Nubium_. The mean height of the _Carpathians_ is about 6,000 feet, the alt.i.tude of certain points in the Pyrenees such as the _Port of Pineda_, or _Roland's Breach_, in the shadow of _Mont Perdu_.

The northern slopes of the _Carpathians_ sink rapidly towards the sh.o.r.es of the vast _Mare Imbrium_.

Towards two o'clock in the morning, Barbican calculated the Projectile to be on the 20th northern parallel, and therefore almost immediately over the little ring mountain called _Pytheas_, about 4600 feet in height. The distance of the travellers from the Moon at this point could not be more than about 750 miles, reduced to about 7 by means of their excellent telescopes.

_Mare Imbrium_, the Sea of Rains here revealed itself in all its vastness to the eyes of the travellers, though it must be acknowledged that the immense depression so called, did not afford them a very clear idea regarding its exact boundaries. Right ahead of them rose _Lambert_ about a mile in height; and further on, more to the left, in the direction of _Ocea.n.u.s Procellarum_, _Euler_ revealed itself by its glittering radiations. This mountain, of about the same height as _Lambert_, had been the object of very interesting calculations on the part of Schroeter of Erfurt. This keen observer, desirous of inquiring into the probable origin of the lunar mountains, had proposed to himself the following question: Does the volume of the crater appear to be equal to that of the surrounding ramparts? His calculations showing him that this was generally the case, he naturally concluded that these ramparts must therefore have been the product of a single eruption, for successive eruptions of volcanic matter would have disturbed this correlation. _Euler_ alone, he found, to be an exception to this general law, as the volume of its crater appeared to be twice as great as that of the ma.s.s surrounding it. It must therefore have been formed by several eruptions in succession, but in that case what had become of the ejected matter?

Theories of this nature and all manner of scientific questions were, of course, perfectly permissible to terrestrial astronomers laboring under the disadvantage of imperfect instruments. But Barbican could not think of wasting his time in any speculation of the kind, and now, seeing that his Projectile perceptibly approached the lunar disc, though he despaired of ever reaching it, he was more sanguine than ever of being soon able to discover positively and unquestionably some of the secrets of its formation.

[Footnote C: We must again remind our readers that, in our map, though every thing is set down as it appears to the eye not as it is reversed by the telescope, still, for the reason made so clear by Barbican, the right hand side must be the west and the left the east.]

CHAPTER XIII.

LUNAR LANDSCAPES

At half past two in the morning of December 6th, the travellers crossed the 30th northern parallel, at a distance from the lunar surface of 625 miles, reduced to about 6 by their spy-gla.s.ses. Barbican could not yet see the least probability of their landing at any point of the disc. The velocity of the Projectile was decidedly slow, but for that reason extremely puzzling. Barbican could not account for it. At such a proximity to the Moon, the velocity, one would think, should be very great indeed to be able to counteract the lunar attraction. Why did it not fall? Barbican could not tell; his companions were equally in the dark. Ardan said he gave it up. Besides they had no time to spend in investigating it. The lunar panorama was unrolling all its splendors beneath them, and they could not bear to lose one of its slightest details.

The lunar disc being brought within a distance of about six miles by the spy-gla.s.ses, it is a fair question to ask, what _could_ an aeronaut at such an elevation from our Earth discover on its surface? At present that question can hardly be answered, the most remarkable balloon ascensions never having pa.s.sed an alt.i.tude of five miles under circ.u.mstances favorable for observers. Here, however, is an account, carefully transcribed from notes taken on the spot, of what Barbican and his companions _did_ see from their peculiar post of observation.

Varieties of color, in the first place, appeared here and there upon the disc. Selenographers are not quite agreed as to the nature of these colors. Not that such colors are without variety or too faint to be easily distinguished. Schmidt of Athens even says that if our oceans on earth were all evaporated, an observer in the Moon would hardly find the seas and continents of our globe even so well outlined as those of the Moon are to the eye of a terrestrial observer. According to him, the shade of color distinguis.h.i.+ng those vast plains known as "seas" is a dark gray dashed with green and brown,--a color presented also by a few of the great craters.

This opinion of Schmidt's, shared by Beer and Maedler, Barbican's observations now convinced him to be far better founded than that of certain astronomers who admit of no color at all being visible on the Moon's surface but gray. In certain spots the greenish tint was quite decided, particularly in _Mare Serenitatis_ and _Mare Humorum,_ the very localities where Schmidt had most noticed it. Barbican also remarked that several large craters, of the cla.s.s that had no interior cones, reflected a kind of bluish tinge, somewhat like that given forth by a freshly polished steel plate. These tints, he now saw enough to convince him, proceeded really from the lunar surface, and were not due, as certain astronomers a.s.serted, either to the imperfections of the spy-gla.s.ses, or to the interference of the terrestrial atmosphere. His singular opportunity for correct observation allowed him to entertain no doubt whatever on the subject. Hampered by no atmosphere, he was free from all liability to optical illusion. Satisfied therefore as to the reality of these tints, he considered such knowledge a positive gain to science. But that greenish tint--to what was it due? To a dense tropical vegetation maintained by a low atmosphere, a mile or so in thickness?

Possibly. But this was another question that could not be answered at present.

Further on he could detect here and there traces of a decidedly ruddy tint. Such a shade he knew had been already detected in the _Palus Somnii_, near _Mare Crisium_, and in the circular area of _Lichtenberg_, near the _Hercynian Mountains_, on the eastern edge of the Moon. To what cause was this tint to be attributed? To the actual color of the surface itself? Or to that of the lava covering it here and there? Or to the color resulting from the mixture of other colors seen at a distance too great to allow of their being distinguished separately? Impossible to tell.

Barbican and his companions succeeded no better at a new problem that soon engaged their undivided attention. It deserves some detail.

Having pa.s.sed _Lambert_, being just over _Timocharis_, all were attentively gazing at the magnificent crater of _Archimedes_ with a diameter of 52 miles across and ramparts more than 5000 feet in height, when Ardan startled his companions by suddenly exclaiming:

"h.e.l.lo! Cultivated fields as I am a living man!"

"What do you mean by your cultivated fields?" asked M'Nicholl sourly, wiping his gla.s.ses and shrugging his shoulders.

"Certainly cultivated fields!" replied Ardan. "Don't you see the furrows? They're certainly plain enough. They are white too from glistening in the sun, but they are quite different from the radiating streaks of _Copernicus_. Why, their sides are perfectly parallel!"

"Where are those furrows?" asked M'Nicholl, putting his gla.s.ses to his eye and adjusting the focus.

"You can see them in all directions," answered Ardan; "but two are particularly visible: one running north from _Archimedes_, the other south towards the _Apennines_."

M'Nicholl's face, as he gazed, gradually a.s.sumed a grin which soon developed into a snicker, if not a positive laugh, as he observed to Ardan:

"Your Selenites must be Brobdignagians, their oxen Leviathans, and their ploughs bigger than Marston's famous cannon, if these are furrows!"

"How's that, Barbican?" asked Ardan doubtfully, but unwilling to submit to M'Nicholl.

"They're not furrows, dear friend," said Barbican, "and can't be, either, simply on account of their immense size. They are what the German astronomers called _Rillen_; the French, _rainures_, and the English, _grooves_, _ca.n.a.ls_, _clefts_, _cracks_, _chasms_, or _fissures_."

"You have a good stock of names for them anyhow," observed Ardan, "if that does any good."

"The number of names given them," answered Barbican, "shows how little is really known about them. They have been observed in all the level portion of the Moon's surface. Small as they appear to us, a little calculation must convince you that they are in some places hundreds of miles in length, a mile in width and probably in many points several miles in depth. Their width and depth, however, vary, though their sides, so far as observed, are always rigorously parallel. Let us take a good look at them."

Putting the gla.s.s to his eye, Barbican examined the clefts for some time with close attention. He saw that their banks were sharp edged and extremely steep. In many places they were of such geometrical regularity that he readily excused Gruithuysen's idea of deeming them to be gigantic earthworks thrown up by the Selenite engineers. Some of them were as straight as if laid out with a line, others were curved a little here and there, though still maintaining the strict parallelism of their sides. These crossed each other; those entered craters and came out at the other side. Here, they furrowed annular plateaus, such as _Posidonius_ or _Petavius_. There, they wrinkled whole seas, for instance, _Mare Serenitatis_.

These curious peculiarities of the lunar surface had interested the astronomic mind to a very high degree at their first discovery, and have proved to be very perplexing problems ever since. The first observers do not seem to have noticed them. Neither Hevelius, nor Ca.s.sini, nor La Hire, nor Herschel, makes a single remark regarding their nature.

It was Schroeter, in 1789, who called the attention of scientists to them for the first time. He had only 11 to show, but Lohrmann soon recorded 75 more. Pastorff, Gruithuysen, and particularly Beer and Maedler were still more successful, but Julius Schmidt, the famous astronomer of Athens, has raised their number up to 425, and has even published their names in a catalogue. But counting them is one thing, determining their nature is another. They are not fortifications, certainly: and cannot be ancient beds of dried up rivers, for two very good and sufficient reasons: first, water, even under the most favorable circ.u.mstances on the Moon's surface, could have never ploughed up such vast channels; secondly, these chasms often traverse lofty craters through and through, like an immense railroad cutting.

At these details, Ardan's imagination became unusually excited and of course it was not without some result. It even happened that he hit on an idea that had already suggested itself to Schmidt of Athens.

"Why not consider them," he asked, "to be the simple phenomena of vegetation?"

"What do you mean?" asked Barbican.

"Rows of sugar cane?" suggested M'Nicholl with a snicker.

"Not exactly, my worthy Captain," answered Ardan quietly, "though you were perhaps nearer to the mark than you expected. I don't mean exactly rows of sugar cane, but I do mean vast avenues of trees--poplars, for instance--planted regularly on each side of a great high road."

"Still harping on vegetation!" said the Captain. "Ardan, what a splendid historian was spoiled in you! The less you know about your facts, the readier you are to account for them."

"_Ma foi_," said Ardan simply, "I do only what the greatest of your scientific men do--that is, guess. There is this difference however between us--I call my guesses, guesses, mere conjecture;--they dignify theirs as profound theories or as astounding discoveries!"

"Often the case, friend Ardan, too often the case," said Barbican.

"In the question under consideration, however," continued the Frenchman, "my conjecture has this advantage over some others: it explains why these rills appear and seem to disappear at regular intervals."