All Around the Moon

  CHAPTER XVI.

  THE SOUTHERN HEMISPHERE.

  Exceedingly narrow and exceedingly fortunate had been the escape of theProjectile. And from a danger too the most unlikely and the mostunexpected. Who would have ever dreamed of even the possibility of suchan encounter? And was all danger over? The sight of one of these erraticbolides certainly justified the gravest apprehensions of our travellersregarding the existence of others. Worse than the sunken reefs of theSouthern Seas or the snags of the Mississippi, how could the Projectilebe expected to avoid them? Drifting along blindly through the boundlessethereal ocean, _her_ inmates, even if they saw the danger, were totallypowerless to turn her aside. Like a ship without a rudder, like arunaway horse, like a collapsed balloon, like an iceberg in an Atlanticstorm, like a boat in the Niagara rapids, she moved on sullenly,recklessly, mechanically, mayhap into the very jaws of the mostfrightful danger, the bright intelligences within no more able to modifyher motions even by a finger's breadth than they were able to affectMercury's movements around the Sun.

  But did our friends complain of the new perils now looming up beforethem? They never thought of such a thing. On the contrary, they onlyconsidered themselves (after the lapse of a few minutes to calm theirnerves) extremely lucky in having witnessed this fresh glory ofexuberant nature, this transcendent display of fireworks which not onlycast into absolute insignificance anything of the kind they had everseen on Earth, but had actually enabled them by its dazzlingillumination to gaze for a second or two at the Moon's mysteriousinvisible disc. This glorious momentary glance, worth a whole lifetimeof ordinary existence, had revealed to mortal ken her continents, heroceans, her forests. But did it also convince them of the existence ofan atmosphere on her surface whose vivifying molecules would render_life_ possible? This question they had again to leave unanswered--itwill hardly ever be answered in a way quite satisfactory to humancuriosity. Still, infinite was their satisfaction at having hovered evenfor an instant on the very verge of such a great problem's solution.

  It was now half-past three in the afternoon. The Projectile stillpursued its curving but otherwise unknown path over the Moon's invisibleface. Had this path been disturbed by that dangerous meteor? There wasevery reason to fear so--though, disturbance or no disturbance, thecurve it described should still be one strictly in accordance with thelaws of Mechanical Philosophy. Whether it was a parabola or a hyperbola,however, or whether it was disturbed or not, made very little differenceas, in any case, the Projectile was bound to quit pretty soon the coneof the shadow, at a point directly opposite to where it had entered it.This cone could not possibly be of very great extent, considering thevery slight ratio borne by the Moon's diameter when compared with theSun's. Still, to all appearances, the Projectile seemed to be quite asdeeply immersed in the shadow as ever, and there was apparently not theslightest sign of such a state of things coming soon to an end. At whatrate was the Projectile now moving? Hard to say, but certainly notslowly, certainly rapidly enough to be out of the shadow by this time,if describing a curve rigidly parabolic. Was the curve therefore _not_parabolic? Another puzzling problem and sadly bewildering to poorBarbican, who had now almost lost his reason by attempting to clear upquestions that were proving altogether too profound for his overworkedbrains.

  Not that he ever thought of taking rest. Not that his companions thoughtof taking rest. Far from it. With senses as high-strung as ever, theystill watched carefully for every new fact, every unexpected incidentthat might throw some light on the sidereal investigations. Even theirdinner, or what was called so, consisted of only a few bits of bread andmeat, distributed by Ardan at five o'clock, and swallowed mechanically.They did not even turn on the gas full head to see what they wereeating; each man stood solidly at his window, the glass of which theyhad enough to do in keeping free from the rapidly condensing moisture.

  At about half-past five, however, M'Nicholl, who had been gazing forsome time with his telescope in a particular direction, called theattention of his companions to some bright specks of light barelydiscernible in that part of the horizon towards which the Projectile wasevidently moving. His words were hardly uttered when his companionsannounced the same discovery. They could soon all see the glitteringspecks not only becoming more and more numerous, but also graduallyassuming the shape of an extremely slender, but extremely brilliantcrescent. Rapidly more brilliant and more decided in shape the profilegradually grew, till it soon resembled the first faint sketch of the NewMoon that we catch of evenings in the western sky, or rather the firstglimpse we get of her limb as it slowly moves out of eclipse. But it wasinconceivably brighter than either, and was furthermore strangelyrelieved by the pitchy blackness both of sky and Moon. In fact, it soonbecame so brilliant as to dispel in a moment all doubt as to itsparticular nature. No meteor could present such a perfect shape; novolcano, such dazzling splendor.

  "The Sun!" cried Barbican.

  "The Sun?" asked M'Nicholl and Ardan in some astonishment.

  "Yes, dear friends; it is the Sun himself that you now see; thesesummits that you behold him gilding are the mountains that lie on theMoon's southern rim. We are rapidly nearing her south pole."

  "After doubling her north pole!" cried Ardan; "why, we must becircumnavigating her!"

  "Exactly; sailing all around her."

  "Hurrah! Then we're all right at last! There's nothing more to fear fromyour hyperbolas or parabolas or any other of your open curves!"

  "Nothing more, certainly, from an open curve, but every thing from aclosed one."

  "A closed curve! What is it called? And what is the trouble?"

  "An eclipse it is called; and the trouble is that, instead of flying offinto the boundless regions of space, our Projectile will probablydescribe an elliptical orbit around the Moon--"

  --"What!" cried M'Nicholl, in amazement, "and be her satellite forever!"

  "All right and proper," said Ardan; "why shouldn't she have one of herown?"

  "Only, my dear friend," said Barbican to Ardan, "this change of curveinvolves no change in the doom of the Projectile. We are as infalliblylost by an ellipse as by a parabola."

  "Well, there was one thing I never could reconcile myself to in thewhole arrangement," replied Ardan cheerfully; "and that was destructionby an open curve. Safe from that, I could say, 'Fate, do your worst!'Besides, I don't believe in the infallibility of your ellipsic. It mayprove just as unreliable as the hyperbola. And it is no harm to hopethat it may!"

  From present appearances there was very little to justify Ardan's hope.Barbican's theory of the elliptic orbit was unfortunately too wellgrounded to allow a single reasonable doubt to be expressed regardingthe Projectile's fate. It was to gravitate for ever around the Moon--asub-satellite. It was a new born individual in the astral universe, amicrocosm, a little world in itself, containing, however, only threeinhabitants and even these destined to perish pretty soon for want ofair. Our travellers, therefore, had no particular reason for rejoicingover the new destiny reserved for the Projectile in obedience to theinexorable laws of the centripetal and centrifugal forces. They weresoon, it is true, to have the opportunity of beholding once more theilluminated face of the Moon. They might even live long enough to catcha last glimpse of the distant Earth bathed in the glory of the solarrays. They might even have strength enough left to be able to chant onesolemn final eternal adieu to their dear old Mother World, upon whosefeatures their mortal eyes should never again rest in love and longing!Then, what was their Projectile to become? An inert, lifeless, extinctmass, not a particle better than the most defunct asteroid that wandersblindly through the fields of ether. A gloomy fate to look forward to.Yet, instead of grieving over the inevitable, our bold travellersactually felt thrilled with delight at the prospect of even a momentarydeliverance from those gloomy depths of darkness and of once morefinding themselves, even if only for a few hours, in the cheerfulprecincts illuminated by the genial light of the blessed Sun!

  The ring of light, in the meantime, becoming
brighter and brighter,Barbican was not long in discovering and pointing out to his companionsthe different mountains that lay around the Moon's south pole.

  "There is _Leibnitz_ on your right," said he, "and on your left you caneasily see the peaks of _Doerfel_. Belonging rather to the Moon's darkside than to her Earth side, they are visible to terrestrial astronomersonly when she is in her highest northern latitudes. Those faint peaksbeyond them that you can catch with such difficulty must be those of_Newton_ and _Curtius_."

  "How in the world can you tell?" asked Ardan.

  "They are the highest mountains in the circumpolar regions," repliedBarbican. "They have been measured with the greatest care; _Newton_ is23,000 feet high."

  "More or less!" laughed Ardan. "What Delphic oracle says so?"

  "Dear friend," replied Barbican quietly, "the visible mountains of theMoon have been measured so carefully and so accurately that I shouldhardly hesitate in affirming their altitude to be as well known as thatof Mont Blanc, or, at least, as those of the chief peaks in theHimalayahs or the Rocky Mountain Range."

  "I should like to know how people set about it," observed Ardanincredulously.

  "There are several well known methods of approaching this problem,"replied Barbican; "and as these methods, though founded on differentprinciples, bring us constantly to the same result, we may prettysafely conclude that our calculations are right. We have no time, justnow to draw diagrams, but, if I express myself clearly, you will nodoubt easily catch the general principle."

  "Go ahead!" answered Ardan. "Anything but Algebra."

  "We want no Algebra now," said Barbican, "It can't enable us to findprinciples, though it certainly enables us to apply them. Well. The Sunat a certain altitude shines on one side of a mountain and flings ashadow on the other. The length of this shadow is easily found by meansof a telescope, whose object glass is provided with a micrometer. Thisconsists simply of two parallel spider threads, one of which isstationary and the other movable. The Moon's real diameter being knownand occupying a certain space on the object glass, the exact spaceoccupied by the shadow can be easily ascertained by means of the movablethread. This space, compared with the Moon's space, will give us thelength of the shadow. Now, as under the same circumstances a certainheight can cast only a certain shadow, of course a knowledge of the onemust give you that of the other, and _vice versa_. This method, statedroughly, was that followed by Galileo, and, in our own day, by Beer andMaedler, with extraordinary success."

  "I certainly see some sense in this method," said Ardan, "if they tookextraordinary pains to observe correctly. The least carelessness wouldset them wrong, not only by feet but by miles. We have time enough,however, to listen to another method before we get into the full blazeof the glorious old Sol."

  "The other method," interrupted M'Nicholl laying down his telescope torest his eyes, and now joining in the conversation to give himselfsomething to do, "is called that of the _tangent rays_. A solar ray,barely passing the edge of the Moon's surface, is caught on the peak ofa mountain the rest of which lies in shadow. The distance between thisstarry peak and the line separating the light from the darkness, wemeasure carefully by means of our telescope. Then--"

  "I see it at a glance!" interrupted Ardan with lighting eye; "the ray,being a tangent, of course makes right angles with the radius, which isknown: consequently we have two sides and one angle--quite enough tofind the other parts of the triangle. Very ingenious--but now, that Ithink of it--is not this method absolutely impracticable for everymountain except those in the immediate neighborhood of the light andshadow line?"

  "That's a defect easily remedied by patience," explained Barbican--theCaptain, who did not like being interrupted, having withdrawn to histelescope--"As this line is continually changing, in course of time allthe mountains must come near it. A third method--to measure the mountainprofile directly by means of the micrometer--is evidently applicableonly to altitudes lying exactly on the lunar rim."

  "That is clear enough," said Ardan, "and another point is also veryclear. In Full Moon no measurement is possible. When no shadows aremade, none can be measured. Measurements, right or wrong, are possibleonly when the solar rays strike the Moon's surface obliquely with regardto the observer. Am I right, Signor Barbicani, maestro illustrissimo?"

  "Perfectly right," replied Barbican. "You are an apt pupil."

  "Say that again," said Ardan. "I want Mac to hear it."

  Barbican humored him by repeating the observation, but M'Nicholl wouldonly notice it by a grunt of doubtful meaning.

  "Was Galileo tolerably successful in his calculations?" asked Ardan,resuming the conversation.

  Before answering this question, Barbican unrolled the map of the Moon,which a faint light like that of day-break now enabled him to examine.He then went on: "Galileo was wonderfully successful--considering thatthe telescope which he employed was a poor instrument of his ownconstruction, magnifying only thirty times. He gave the lunar mountainsa height of about 26,000 feet--an altitude cut down by Hevelius, butalmost doubled by Riccioli. Herschel was the first to come pretty closeto the truth, but Beer and Maedler, whose _Mappa Selenographica_ nowlies before us, have left really nothing more to be done for lunarastronomy--except, of course, to pay a personal visit to theMoon--which we have tried to do, but I fear with a very poor prospect ofsuccess."

  "Cheer up! cheer up!" cried Ardan. "It's not all over yet by long odds.Who can say what is still in store for us? Another bolide may shunt usoff our ellipse and even send us to the Moon's surface."

  Then seeing Barbican shake his head ominously and his countenance becomemore and more depressed, this true friend tried to brighten him up a bitby feigning to take deep interest in a subject that to him wasabsolutely the driest in the world.

  "Meer and Baedler--I mean Beer and Maedler," he went on, "must havemeasured at least forty or fifty mountains to their satisfaction."

  "Forty or fifty!" exclaimed Barbican. "They measured no fewer than athousand and ninety-five lunar mountains and crater summits with aperfect success. Six of these reach an altitude of upwards of 18,000feet, and twenty-two are more than 15,000 feet high."

  "Which is the highest in the lot?" asked Ardan, keenly relishingBarbican's earnestness.

  "_Doerfel_ in the southern hemisphere, the peak of which I have justpointed out, is the highest of the lunar mountains so far measured,"replied Barbican. "It is nearly 25,000 feet high."

  "Indeed! Five thousand feet lower than Mount Everest--still for a lunarmountain, it is quite a respectable altitude."

  "Respectable! Why it's an enormous altitude, my dear friend, if youcompare it with the Moon's diameter. The Earth's diameter being morethan 3-1/2 times greater than the Moon's, if the Earth's mountains borethe same ratio to those of the Moon, Everest should be more than sixteenmiles high, whereas it is not quite six."

  "How do the general heights of the Himalayahs compare with those of thehighest lunar mountains?" asked Ardan, wondering what would be his nextquestion.

  "Fifteen peaks in the eastern or higher division of the Himalayahs, arehigher than the loftiest lunar peaks," replied Barbican. "Even in thewestern, or lower section of the Himalayahs, some of the peaks exceed_Doerfel_."

  "Which are the chief lunar mountains that exceed Mont Blanc inaltitude?" asked Ardan, bravely suppressing a yawn.

  "The following dozen, ranged, if my memory does not fail me, in theexact order of their respective heights;" replied Barbican, neverwearied in answering such questions: "_Newton_, _Curtius_, _Casatus_,_Rheita_, _Short_, _Huyghens_, _Biancanus_, _Tycho_, _Kircher_,_Clavius_, _Endymion_, and _Catharina_."

  "Now those not quite up to Mont Blanc?" asked Ardan, hardly knowing whatto say.

  "Here they are, about half a dozen of them: _Moretus_, _Theophilus_,_Harpalus_, _Eratosthenes_, _Werner_, and _Piccolomini_," answeredBarbican as ready as a schoolboy reciting his lesson, and pointing themout on the map as quickly as a compositor distributing his type.

  "The next in ran
k?" asked Ardan, astounded at his friend's wonderfulmemory.

  "The next in rank," replied Barbican promptly, "are those about the sizeof the Matterhorn, that is to say about 2-3/4 miles in height. They are_Macrobius_, _Delambre_, and _Conon_. Come," he added, seeing Ardanhesitating and at a loss what other question to ask, "don't you want toknow what lunar mountains are about the same height as the Peak ofTeneriffe? or as AEtna? or as Mount Washington? You need not be afraid ofpuzzling me. I studied up the subject thoroughly, and therefore know allabout it."

  "Oh! I could listen to you with delight all day long!" cried Ardan,enthusiastically, though with some embarrassment, for he felt a twingeof conscience in acting so falsely towards his beloved friend. "The factis," he went on, "such a rational conversation as the present, on suchan absorbing subject, with such a perfect master--"

  "The Sun!" cried M'Nicholl starting up and cheering. "He's cleared thedisc completely, and he's now himself again! Long life to him! Hurrah!"

  "Hurrah!" cried the others quite as enthusiastically (Ardan did not seema bit desirous to finish his sentence).

  They tossed their maps aside and hastened to the window.