Read All Around the Moon Page 19


  CHAPTER XVIII.

  PUZZLING QUESTIONS.

  It was not until the Projectile had passed a little beyond _Tycho's_immense concavity that Barbican and his friends had a good opportunityfor observing the brilliant streaks sent so wonderfully flying in alldirections from this celebrated mountain as a common centre. Theyexamined them for some time with the closest attention.

  What could be the nature of this radiating aureola? By what geologicalphenomena could this blazing coma have been possibly produced? Suchquestions were the most natural things in the world for Barbican and hiscompanions to propound to themselves, as indeed they have been to everyastronomer from the beginning of time, and probably will be to the end.

  What _did_ they see? What you can see, what anybody can see on a clearnight when the Moon is full--only our friends had all the advantages ofa closer view. From _Tycho_, as a focus, radiated in all directions, asfrom the head of a peeled orange, more than a hundred luminous streaksor channels, edges raised, middle depressed--or perhaps _vice versa_,owing to an optical illusion--some at least twelve miles wide, somefully thirty. In certain directions they ran for a distance of at leastsix hundred miles, and seemed--especially towards the west, northwest,and north--to cover half the southern hemisphere. One of these flashesextended as far as _Neander_ on the 40th meridian; another, curvingaround so as to furrow the _Mare Nectaris_, came to an end on the chainof the _Pyrenees_, after a course of perhaps a little more than sevenhundred miles. On the east, some of them barred with luminous networkthe _Mare Nubium_ and even the _Mare Humorum_.

  The most puzzling feature of these glittering streaks was that they rantheir course directly onward, apparently neither obstructed by valley,crater, or mountain ridge however high. They all started, as saidbefore, from one common focus, _Tycho's_ crater. From this theycertainly all seemed to emanate. Could they be rivers of lava oncevomited from that centre by resistless volcanic agency and afterwardscrystallized into glassy rock? This idea of Herschel's, Barbican had nohesitation in qualifying as exceedingly absurd. Rivers running inperfectly straight lines, across plains, and _up_ as well as _down_mountains!

  "Other astronomers," he continued, "have looked on these streaks as apeculiar kind of _moraines_, that is, long lines of erratic blocksbelched forth with mighty power at the period of _Tycho's_ ownupheaval."

  "How do you like that theory, Barbican," asked the Captain.

  "It's not a particle better than Herschel's," was the reply; "novolcanic action could project rocks to a distance of six or sevenhundred miles, not to talk of laying them down so regularly that wecan't detect a break in them."

  "Happy thought!" cried Ardan suddenly; "it seems to me that I can tellthe cause of these radiating streaks!"

  "Let us hear it," said Barbican.

  "Certainly," was Ardan's reply; "these streaks are all only the parts ofwhat we call a 'star,' as made by a stone striking ice; or by a ball, apane of glass."

  "Not bad," smiled Barbican approvingly; "only where is the hand thatflung the stone or threw the ball?"

  "The hand is hardly necessary," replied Ardan, by no means disconcerted;"but as for the ball, what do you say to a comet?"

  Here M'Nicholl laughed so loud that Ardan was seriously irritated.However, before he could say anything cutting enough to make the Captainmind his manners, Barbican had quickly resumed:

  "Dear friend, let the comets alone, I beg of you; the old astronomersfled to them on all occasions and made them explain every difficulty--"

  --"The comets were all used up long ago--" interrupted M'Nicholl.

  --"Yes," went on Barbican, as serenely as a judge, "comets, they said,had fallen on the surface in meteoric showers and crushed in the cratercavities; comets had dried up the water; comets had whisked off theatmosphere; comets had done everything. All pure assumption! In yourcase, however, friend Michael, no comet whatever is necessary. The shockthat gave rise to your great 'star' may have come from the interiorrather than the exterior. A violent contraction of the lunar crust inthe process of cooling may have given birth to your gigantic 'star'formation."

  "I accept the amendment," said Ardan, now in the best of humor andlooking triumphantly at M'Nicholl.

  "An English scientist," continued Barbican, "Nasmyth by name, isdecidedly of your opinion, especially ever since a little experiment ofhis own has confirmed him in it. He filled a glass globe with water,hermetically sealed it, and then plunged it into a hot bath. Theenclosed water, expanding at a greater rate than the glass, burst thelatter, but, in doing so, it made a vast number of cracks all divergingin every direction from the focus of disruption. Something like this heconceives to have taken place around _Tycho_. As the crust cooled, itcracked. The lava from the interior, oozing out, spread itself on bothsides of the cracks. This certainly explains pretty satisfactorily whythose flat glistening streaks are of much greater width than thefissures through which the lava had at first made its way to thesurface."

  "Well done for an Englishman!" cried Ardan in great spirits.

  "He's no Englishman," said M'Nicholl, glad to have an opportunity ofcoming off with some credit. "He is the famous Scotch engineer whoinvented the steam hammer, the steam ram, and discovered the 'willowleaves' in the Sun's disc."

  "Better and better," said Ardan--"but, powers of Vulcan! What makes itso hot? I'm actually roasting!"

  This observation was hardly necessary to make his companions consciousthat by this time they felt extremely uncomfortable. The heat had becomequite oppressive. Between the natural caloric of the Sun and thereflected caloric of the Moon, the Projectile was fast turning into aregular bake oven. This transition from intense cold to intense heat wasalready about quite as much as they could bear.

  "What shall we do, Barbican?" asked Ardan, seeing that for some time noone else appeared inclined to say a word.

  "Nothing, at least yet awhile, friend Ardan," replied Barbican, "I havebeen watching the thermometer carefully for the last few minutes, and,though we are at present at 38 deg. centigrade, or 100 deg. Fahrenheit, I havenoticed that the mercury is slowly falling. You can also easily remarkfor yourself that the floor of the Projectile is turning away more andmore from the lunar surface. From this I conclude quite confidently, andI see that the Captain agrees with me, that all danger of death fromintense heat, though decidedly alarming ten minutes ago, is over for thepresent and, for some time at least, it may be dismissed from furtherconsideration."

  "I'm not very sorry for it," said Ardan cheerfully; "neither to bebaked like a pie in an oven nor roasted like a fat goose before a fireis the kind of death I should like to die of."

  "Yet from such a death you would suffer no more than your friends theSelenites are exposed to every day of their lives," said the Captain,evidently determined on getting up an argument.

  "I understand the full bearing of your allusion, my dear Captain,"replied Ardan quickly, but not at all in a tone showing that he wasdisposed to second M'Nicholl's expectations.

  He was, in fact, fast losing all his old habits of positivism. Latterlyhe had seen much, but he had reflected more. The deeper he hadreflected, the more inclined he had become to accept the conclusion thatthe less he knew. Hence he had decided that if M'Nicholl wanted anargument it should not be with him. All speculative disputes he shouldhenceforth avoid; he would listen with pleasure to all that could beurged on each side; he might even skirmish a little here and there asthe spirit moved him; but a regular pitched battle on a subject purelyspeculative he was fully determined never again to enter into.

  "Yes, dear Captain," he continued, "that pointed arrow of yours has byno means missed its mark, but I can't deny that my faith is beginning tobe what you call a little 'shaky' in the existence of my friends theSelenites. However, I should like to have your square opinion on thematter. Barbican's also. We have witnessed many strange lunar phenomenalately, closer and clearer than mortal eye ever rested on them before.Has what we have seen confirmed any theory of yours or confounded anyhypothesis? Have
you seen enough to induce you to adopt decidedconclusions? I will put the question formally. Do you, or do you not,think that the Moon resembles the Earth in being the abode of animalsand intelligent beings? Come, answer, _messieurs_. Yes, or no?"

  "I think we can answer your question categorically," replied Barbican,"if you modify its form a little."

  "Put the question any way you please," said Ardan; "only you answer it!I'm not particular about the form."

  "Good," said Barbican; "the question, being a double one, demands adouble answer. First: _Is the Moon inhabitable?_ Second: _Has the Moonever been inhabited?_"

  "That's the way to go about it," said the Captain. "Now then, Ardan,what do _you_ say to the first question? Yes, or no?"

  "I really can't say anything," replied Ardan. "In the presence of suchdistinguished scientists, I'm only a listener, a 'mere looker on inVienna' as the Divine Williams has it. However, for the sake ofargument, suppose I reply in the affirmative, and say that _the Moon isinhabitable_."

  "If you do, I shall most unhesitatingly contradict you," said Barbican,feeling just then in splendid humor for carrying on an argument, not, ofcourse, for the sake of contradicting or conquering or crushing orshowing off or for any other vulgar weakness of lower minds, but for thenoble and indeed the only motive that should impel a philosopher--thatof _enlightening_ and _convincing_, "In taking the negative side,however, or saying that the Moon is not inhabitable, I shall not besatisfied with merely negative arguments. Many words, however, are notrequired. Look at her present condition: her atmosphere dwindled away tothe lowest ebb; her 'seas' dried up or very nearly so; her watersreduced to next to nothing; her vegetation, if existing at all, existingonly on the scantiest scale; her transitions from intense heat tointense cold, as we ourselves can testify, sudden in the extreme; hernights and her days each nearly 360 hours long. With all this positivelyagainst her and nothing at all that we know of positively for her, Ihave very little hesitation in saying that the Moon appears to me to beabsolutely uninhabitable. She seems to me not only unpropitious to thedevelopment of the animal kingdom but actually incapable of sustaininglife at all--that is, in the sense that we usually attach to such aterm."

  "That saving clause is well introduced, friend Barbican," saidM'Nicholl, who, seeing no chance of demolishing Ardan, had not yet madeup his mind as to having another little bout with the President. "Forsurely you would not venture to assert that the Moon is uninhabitable bya race of beings having an organization different from ours?"

  "That question too, Captain," replied Barbican, "though a much moredifficult one, I shall try to answer. First, however, let us see,Captain, if we agree on some fundamental points. How do we detect theexistence of life? Is it not by _movement_? Is not _motion_ its result,no matter what may be its organization?"

  "Well," said the Captain in a drawling way, "I guess we may grant that."

  "Then, dear friends," resumed Barbican, "I must remind you that, thoughwe have had the privilege of observing the lunar continents at adistance of not more than one-third of a mile, we have never yet caughtsight of the first thing moving on her surface. The presence ofhumanity, even of the lowest type, would have revealed itself in someform or other, by boundaries, by buildings, even by ruins. Now what_have_ we seen? Everywhere and always, the geological works of _nature_;nowhere and never, the orderly labors of _man_. Therefore, if anyrepresentatives of animal life exist in the Moon, they must have takenrefuge in those bottomless abysses where our eyes were unable to trackthem. And even this I can't admit. They could not always remain in thesecavities. If there is any atmosphere at all in the Moon, it must befound in her immense low-lying plains. Over those plains her inhabitantsmust have often passed, and on those plains they must in some way orother have left some mark, some trace, some vestige of their existence,were it even only a road. But you both know well that nowhere are anysuch traces visible: therefore, they don't exist; therefore, no lunarinhabitants exist--except, of course, such a race of beings, if we canimagine any such, as could exist without revealing their existence by_movement_."

  "That is to say," broke in Ardan, to give what he conceived a sharperpoint to Barbican's cogent arguments, "such a race of beings as couldexist without existing!"

  "Precisely," said Barbican: "Life without movement, and no life at all,are equivalent expressions."

  "Captain," said Ardan, with all the gravity he could assume, "have youanything more to say before the Moderator of our little Debating Societygives his opinion on the arguments regarding the question before thehouse?"

  "No more at present," said the Captain, biding his time.

  "Then," resumed Ardan, rising with much dignity, "the Committee on LunarExplorations, appointed by the Honorable Baltimore Gun Club, solemnlyassembled in the Projectile belonging to the aforesaid learned andrespectable Society, having carefully weighed all the arguments advancedon each side of the question, and having also carefully considered allthe new facts bearing on the case that have lately come under thepersonal notice of said Committee, unanimously decides negatively on thequestion now before the chair for investigation--namely, 'Is the Mooninhabitable?' Barbican, as chairman of the Committee, I empower you toduly record our solemn decision--_No, the Moon is not inhabitable_."

  Barbican, opening his note-book, made the proper entry among the minutesof the meeting of December 6th.

  "Now then, gentlemen," continued Ardan, "if you are ready for the secondquestion, the necessary complement of the first, we may as well approachit at once. I propound it for discussion in the following form: _Has theMoon ever been inhabited?_ Captain, the Committee would be delighted tohear your remarks on the subject."

  "Gentlemen," began the Captain in reply, "I had formed my opinionregarding the ancient inhabitability of our Satellite long before I everdreamed of testing my theory by anything like our present journey. Iwill now add that all our observations, so far made, have only served toconfirm me in my opinion. I now venture to assert, not only with everykind of probability in my favor but also on what I consider mostexcellent arguments, that the Moon was once inhabited by a race ofbeings possessing an organization similar to our own, that she onceproduced animals anatomically resembling our terrestrial animals, andthat all these living organizations, human and animal, have had theirday, that that day vanished ages and ages ago, and that, consequently,_Life_, extinguished forever, can never again reveal its existence thereunder any form."

  "Is the Chair," asked Ardan, "to infer from the honorable gentleman'sobservations that he considers the Moon to be a world much older thanthe Earth?"

  "Not exactly that," replied the Captain without hesitation; "I rathermean to say that the Moon is a world that grew old more rapidly than theEarth; that it came to maturity earlier; that it ripened quicker, andwas stricken with old age sooner. Owing to the difference of the volumesof the two worlds, the organizing forces of matter must have beencomparatively much more violent in the interior of the Moon than in theinterior of the Earth. The present condition of its surface, as we seeit lying there beneath us at this moment, places this assertion beyondall possibility of doubt. Wrinkled, pitted, knotted, furrowed, scarred,nothing that we can show on Earth resembles it. Moon and Earth werecalled into existence by the Creator probably at the same period oftime. In the first stages of their existence, they do not seem to havebeen anything better than masses of gas. Acted upon by various forcesand various influences, all of course directed by an omnipotentintelligence, these gases by degrees became liquid, and the liquids grewcondensed into solids until solidity could retain its shape. But the twoheavenly bodies, though starting at the same time, developed at a verydifferent ratio. Most undoubtedly, our globe was still gaseous or atmost only liquid, at the period when the Moon, already hardened bycooling, began to become inhabitable."

  "_Most undoubtedly_ is good!" observed Ardan admiringly.

  "At this period," continued the learned Captain, "an atmospheresurrounded her. The waters, shut in by this gaseous envelope, could
nolonger evaporate. Under the combined influences of air, water, light,and solar heat as well as internal heat, vegetation began to overspreadthe continents by this time ready to receive it, and most undoubtedly--Imean--a--incontestably--it was at this epoch that _life_ manifesteditself on the lunar surface. I say _incontestably_ advisedly, for Naturenever exhausts herself in producing useless things, and therefore aworld, so wonderfully inhabitable, _must_ of necessity have hadinhabitants."

  "I like _of necessity_ too," said Ardan, who could never keep still; "Ialways did, when I felt my arguments to be what you call a littleshaky."

  "But, my dear Captain," here observed Barbican, "have you taken intoconsideration some of the peculiarities of our Satellite which aredecidedly opposed to the development of vegetable and animal existence?Those nights and days, for instance, 354 hours long?"

  "I have considered them all," answered the brave Captain. "Days andnights of such an enormous length would at the present time, I grant,give rise to variations in temperature altogether intolerable to anyordinary organization. But things were quite different in the eraalluded to. At that time, the atmosphere enveloped the Moon in a gaseousmantle, and the vapors took the shape of clouds. By the screen thusformed by the hand of nature, the heat of the solar rays was temperedand the nocturnal radiation retarded. Light too, as well as heat, couldbe modified, tempered, and _genialized_ if I may use the expression, bythe air. This produced a healthy counterpoise of forces, which, now thatthe atmosphere has completely disappeared, of course exists no longer.Besides--friend Ardan, you will excuse me for telling you something new,something that will surprise you--"

  --"Surprise me, my dear boy, fire away surprising me!" cried Ardan. "Ilike dearly to be surprised. All I regret is that you scientists havesurprised me so much already that I shall never have a good, hearty,genuine surprise again!"

  --"I am most firmly convinced," continued the Captain, hardly waitingfor Ardan to finish, "that, at the period of the Moon's occupancy byliving creatures, her days and nights were by no means 354 hours long."

  "Well! if anything could surprise me," said Ardan quickly, "such anassertion as that most certainly would. On what does the honorablegentleman base his _most firm conviction_?"

  "We know," replied the Captain, "that the reason of the Moon's presentlong day and night is the exact equality of the periods of her rotationon her axis and of her revolution around the Earth. When she has turnedonce around the Earth, she has turned once around herself. Consequently,her back is turned to the Sun during one-half of the month; and her faceduring the other half. Now, I don't believe that this state of thingsexisted at the period referred to."

  "The gentleman does not believe!" exclaimed Ardan. "The Chair must beexcused for reminding the honorable gentleman that it can not accept hisincredulity as a sound and valid argument. These two movements havecertainly equal periods now; why not always?"

  "For the simple reason that this equality of periods is due altogetherto the influence of terrestrial attraction," replied the ready Captain."This attraction at present, I grant, is so great that it actuallydisables the Moon from revolving on herself; consequently she mustalways keep the same face turned towards the Earth. But who can assertthat this attraction was powerful enough to exert the same influence atthe epoch when the Earth herself was only a fluid substance? In fact,who can even assert that the Moon has always been the Earth'ssatellite?"

  "Ah, who indeed?" exclaimed Ardan. "And who can assert that the Moon didnot exist long before the Earth was called into being at all? In fact,who can assert that the Earth itself is not a great piece broken off theMoon? Nothing like asking absurd questions! I've often found thempassing for the best kind of arguments!"

  "Friend Ardan," interposed Barbican, who noticed that the Captain was alittle too disconcerted to give a ready reply; "Friend Ardan, I must sayyou are not quite wrong in showing how certain methods of reasoning,legitimate enough in themselves, may be easily abused by being carriedtoo far. I think, however, that the Captain might maintain his positionwithout having recourse to speculations altogether too gigantic forordinary intellect. By simply admitting the insufficiency of theprimordeal attraction to preserve a perfect balance between themovements of the lunar rotation and revolution, we can easily see howthe nights and days could once succeed each other on the Moon exactly asthey do at present on the Earth."

  "Nothing can be clearer!" resumed the brave Captain, once more rushingto the charge. "Besides, even without this alternation of days andnights, life on the lunar surface was quite possible."

  "Of course it was possible," said Ardan; "everything is possible exceptwhat contradicts itself. It is possible too that every possibility is afact; therefore, it _is_ a fact. However," he added, not wishing topress the Captain's weak points too closely, "let all these logicalniceties pass for the present. Now that you have established theexistence of your humanity in the Moon, the Chair would respectfully askhow it has all so completely disappeared?"

  "It disappeared completely thousands, perhaps millions, of years ago,"replied the unabashed Captain. "It perished from the physicalimpossibility of living any longer in a world where the atmosphere hadbecome by degrees too rare to be able to perform its functions as thegreat resuscitating medium of dependent existences. What took place onthe Moon is only what is to take place some day or other on the Earth,when it is sufficiently cooled off."

  "Cooled off?"

  "Yes," replied the Captain as confidently and with as little hesitationas if he was explaining some of the details of his great machine-shop inPhiladelphia; "You see, according as the internal fire near the surfacewas extinguished or was withdrawn towards the centre, the lunar shellnaturally cooled off. The logical consequences, of course, thengradually took place: extinction of organized beings; and thenextinction of vegetation. The atmosphere, in the meantime, becamethinner and thinner--partly drawn off with the water evaporated by theterrestrial attraction, and partly sinking with the solid water into thecrust-cracks caused by cooling. With the disappearance of air capable ofrespiration, and of water capable of motion, the Moon, of course, becameuninhabitable. From that day it became the abode of death, as completelyas it is at the present moment."

  "That is the fate in store for our Earth?"

  "In all probability."

  "And when is it to befall us?"

  "Just as soon as the crust becomes cold enough to be uninhabitable."

  "Perhaps your philosophership has taken the trouble to calculate howmany years it will take our unfortunate _Terra Mater_ to cool off?"

  "Well; I have."

  "And you can rely on your figures?"

  "Implicitly."

  "Why not tell it at once then to a fellow that's dying of impatience toknow all about it? Captain, the Chair considers you one of the mosttantalizing creatures in existence!"

  "If you only listen, you will hear," replied M'Nicholl quietly. "Bycareful observations, extended through a series of many years, men havebeen able to discover the average loss of temperature endured by theEarth in a century. Taking this as the ground work of theircalculations, they have ascertained that our Earth shall become anuninhabitable planet in about--"

  "Don't cut her life too short! Be merciful!" cried Ardan in a pleadingtone half in earnest. "Come, a good long day, your Honor! A good longday!"

  "The planet that we call the Earth," continued the Captain, as grave asa judge, "will become uninhabitable to human beings, after a lapse of400 thousand years from the present time."

  "Hurrah!" cried Ardan, much relieved. "_Vive la Science!_ Henceforward,what miscreant will persist in saying that the Savants are good fornothing? Proudly pointing to this calculation, can't they exclaim to alldefamers: 'Silence, croakers! Our services are invaluable! Haven't weinsured the Earth for 400 thousand years?' Again I say _vive laScience!_"

  "Ardan," began the Captain with some asperity, "the foundations onwhich Science has raised--"

  "I'm half converted already," interrupted Ardan in a cheery
tone; "I doreally believe that Science is not altogether unmitigated homebogue!_Vive_--"

  --"But what has all this to do with the question under discussion?"interrupted Barbican, desirous to keep his friends from losing theirtempers in idle disputation.

  "True!" said Ardan. "The Chair, thankful for being called to order,would respectfully remind the house that the question before it is: _Hasthe Moon been inhabited?_ Affirmative has been heard. Negative is calledon to reply. Mr. Barbican has the _parole_."

  But Mr. Barbican was unwilling just then to enter too deeply into suchan exceedingly difficult subject. "The probabilities," he contentedhimself with saying, "would appear to be in favor of the Captain'sspeculations. But we must never forget that they _are_speculations--nothing more. Not the slightest evidence has yet beenproduced that the Moon is anything else than 'a dead and useless wasteof extinct volcanoes.' No signs of cities, no signs of buildings, noteven of ruins, none of anything that could be reasonably ascribed to thelabors of intelligent creatures. No sign of change of any kind has beenestablished. As for the agreement between the Moon's rotation and herrevolution, which compels her to keep the same face constantly turnedtowards the Earth, we don't know that it has not existed from thebeginning. As for what is called the effect of volcanic agency upon hersurface, we don't know that her peculiar blistered appearance may nothave been brought about altogether by the bubbling and spitting thatblisters molten iron when cooling and contracting. Some close observershave even ventured to account for her craters by saying they were due topelting showers of meteoric rain. Then again as to her atmosphere--whyshould she have lost her atmosphere? Why should it sink into craters?Atmosphere is gas, great in volume, small in matter; where would therebe room for it? Solidified by the intense cold? Possibly in the nighttime. But would not the heat of the long day be great enough to thaw itback again? The same trouble attends the alleged disappearance of thewater. Swallowed up in the cavernous cracks, it is said. But why arethere cracks? Cooling is not always attended by cracking. Water coolswithout cracking; cannon balls cool without cracking. Too much stresshas been laid on the great difference between the _nucleus_ and the_crust_: it is really impossible to say where one ends and the otherbegins. In fact, no theory explains satisfactorily anything regardingthe present state of the Moon's surface. In fact, from the day thatGalileo compared her clustering craters to 'eyes on a peacock's tail' tothe present time, we must acknowledge that we know nothing more than wecan actually see, not one particle more of the Moon's history than ourtelescopes reveal to our corporal eyes!"

  "In the lucid opinion of the honorable and learned gentleman who spokelast," said Ardan, "the Chair is compelled to concur. Therefore, as tothe second question before the house for deliberation, _Has the Moonbeen ever inhabited?_ the Chair gets out of its difficulty, as a Scotchjury does when it has not evidence enough either way, by returning asolemn verdict of _Not Proven!_"

  "And with this conclusion," said Barbican, hastily rising, "of a subjecton which, to tell the truth, we are unable as yet to throw any lightworth speaking of, let us be satisfied for the present. Another questionof greater moment to us just now is: where are we? It seems to me thatwe are increasing our distance from the Moon very decidedly and veryrapidly."

  It was easy to see that he was quite right in this observation. TheProjectile, still following a northerly course and therefore approachingthe lunar equator, was certainly getting farther and farther from theMoon. Even at 30 deg. S., only ten degrees farther north than the latitudeof _Tycho_, the travellers had considerable difficulty, comparatively,in observing the details of _Pitatus_, a walled mountain on the southshores of the _Mare Nubium_. In the "sea" itself, over which they nowfloated, they could see very little, but far to the left, on the 20thparallel, they could discern the vast crater of _Bullialdus_, 9,000feet deep. On the right, they had just caught a glimpse of _Purbach_, adepressed valley almost square in shape with a round crater in thecentre, when Ardan suddenly cried out:

  "A Railroad!"

  And, sure enough, right under them, a little northeast of _Purbach_, thetravellers easily distinguished a long line straight and black, reallynot unlike a railroad cutting through a low hilly country.

  This, Barbican explained, was of course no railway, but a steep cliff,at least 1,000 feet high, casting a very deep shadow, and probably theresult of the caving in of the surface on the eastern edge.

  Then they saw the immense crater of _Arzachel_ and in its midst a conemountain shining with dazzling splendor. A little north of this, theycould detect the outlines of another crater, _Alphonse_, at least 70miles in diameter. Close to it they could easily distinguish the immensecrater or, as some observers call it, Ramparted Plain, _Ptolemy_, sowell known to lunar astronomers, occupying, as it does, such a favorableposition near the centre of the Moon, and having a diameter fully, inone direction at least, 120 miles long.

  The travellers were now in about the same latitude as that at which theyhad at first approached the Moon, and it was here that they began mostunquestionably to leave her. They looked and looked, readjusting theirglasses, but the details were becoming more and more difficult to catch.The reliefs grew more and more blurred and the outlines dimmer anddimmer. Even the great mountain profiles began to fade away, thedazzling colors to grow duller, the jet black shadows greyer, and thegeneral effect mistier.

  At last, the distance had become so great that, of this lunar world sowonderful, so fantastic, so weird, so mysterious, our travellers bydegrees lost even the consciousness, and their sensations, lately sovivid, grew fainter and fainter, until finally they resembled those of aman who is suddenly awakened from a peculiarly strange and impressivedream.