by Jules Verne
CHAPTER VI
QUESTION AND ANSWER
On the 4th of December, when the travelers awoke afterfifty-four hours' journey, the chronometer marked five o'clockof the terrestrial morning. In time it was just over fivehours and forty minutes, half of that assigned to their sojournin the projectile; but they had already accomplished nearlyseven-tenths of the way. This peculiarity was due to theirregularly decreasing speed.
Now when they observed the earth through the lower window,it looked like nothing more than a dark spot, drowned in thesolar rays. No more crescent, no more cloudy light! The nextday, at midnight, the earth would be _new_, at the very momentwhen the moon would be full. Above, the orb of night was nearingthe line followed by the projectile, so as to meet it at thegiven hour. All around the black vault was studded with brilliantpoints, which seemed to move slowly; but, at the great distancethey were from them, their relative size did not seem to change.The sun and stars appeared exactly as they do to us upon earth.As to the moon, she was considerably larger; but the travelers'glasses, not very powerful, did not allow them as yet to makeany useful observations upon her surface, or reconnoiter hertopographically or geologically.
Thus the time passed in never-ending conversations all aboutthe moon. Each one brought forward his own contingent ofparticular facts; Barbicane and Nicholl always serious, MichelArdan always enthusiastic. The projectile, its situation,its direction, incidents which might happen, the precautionsnecessitated by their fall on to the moon, were inexhaustiblematters of conjecture.
As they were breakfasting, a question of Michel's, relating tothe projectile, provoked rather a curious answer from Barbicane,which is worth repeating. Michel, supposing it to be roughlystopped, while still under its formidable initial speed, wishedto know what the consequences of the stoppage would have been.
"But," said Barbicane, "I do not see how it could have been stopped."
"But let us suppose so," said Michel.
"It is an impossible supposition," said the practical Barbicane;"unless that impulsive force had failed; but even then its speedwould diminish by degrees, and it would not have stopped suddenly."
"Admit that it had struck a body in space."
"What body?"
"Why that enormous meteor which we met."
"Then," said Nicholl, "the projectile would have been brokeninto a thousand pieces, and we with it."
"More than that," replied Barbicane; "we should have been burnedto death."
"Burned?" exclaimed Michel, "by Jove! I am sorry it did nothappen, `just to see.'"
"And you would have seen," replied Barbicane. "It is known nowthat heat is only a modification of motion. When water iswarmed-- that is to say, when heat is added to it--its particlesare set in motion."
"Well," said michel, "that is an ingenious theory!"
"And a true one, my worthy friend; for it explains everyphenomenon of caloric. Heat is but the motion of atoms, asimple oscillation of the particles of a body. When they applythe brake to a train, the train comes to a stop; but whatbecomes of the motion which it had previously possessed? It istransformed into heat, and the brake becomes hot. Why do theygrease the axles of the wheels? To prevent their heating,because this heat would be generated by the motion which is thuslost by transformation."
"Yes, I understand," replied Michel, "perfectly. For example,when I have run a long time, when I am swimming, when I amperspiring in large drops, why am I obliged to stop?Simply because my motion is changed into heat."
Barbicane could not help smiling at Michel's reply; then,returning to his theory, said:
"Thus, in case of a shock, it would have been with ourprojectile as with a ball which falls in a burning state afterhaving struck the metal plate; it is its motion which is turnedinto heat. Consequently I affirm that, if our projectile hadstruck the meteor, its speed thus suddenly checked would haveraised a heat great enough to turn it into vapor instantaneously."
"Then," asked Nicholl, "what would happen if the earth's motionwere to stop suddenly?"
"Her temperature would be raised to such a pitch," saidBarbicane, "that she would be at once reduced to vapor."
"Well," said Michel, "that is a way of ending the earth whichwill greatly simplify things."
"And if the earth fell upon the sun?" asked Nicholl.
"According to calculation," replied Barbicane, "the fall woulddevelop a heat equal to that produced by 16,000 globes of coal,each equal in bulk to our terrestrial globe."
"Good additional heat for the sun," replied Michel Ardan, "ofwhich the inhabitants of Uranus or Neptune would doubtless notcomplain; they must be perished with cold on their planets."
"Thus, my friends," said Barbicane, "all motion suddenly stoppedproduces heat. And this theory allows us to infer that the heatof the solar disc is fed by a hail of meteors fallingincessantly on its surface. They have even calculated----"
"Oh, dear!" murmured Michel, "the figures are coming."
"They have even calculated," continued the imperturbable Barbicane,"that the shock of each meteor on the sun ought to produce a heatequal to that of 4,000 masses of coal of an equal bulk."
"And what is the solar heat?" asked Michel.
"It is equal to that produced by the combustion of a stratum ofcoal surrounding the sun to a depth of forty-seven miles."
"And that heat----"
"Would be able to boil two billions nine hundred millions ofcubic myriameters [2] of water."
[2] The myriameter is equal to rather more than 10,936cubic yards English.
"And it does not roast us!" exclaimed Michel.
"No," replied Barbicane, "because the terrestrial atmosphereabsorbs four-tenths of the solar heat; besides, the quantity ofheat intercepted by the earth is but a billionth part of theentire radiation."
"I see that all is for the best," said Michel, "and that thisatmosphere is a useful invention; for it not only allows us tobreathe, but it prevents us from roasting."
"Yes!" said Nicholl, "unfortunately, it will not be the same inthe moon."
"Bah!" said Michel, always hopeful. "If there are inhabitants,they must breathe. If there are no longer any, they must haveleft enough oxygen for three people, if only at the bottom ofravines, where its own weight will cause it to accumulate, andwe will not climb the mountains; that is all." And Michel,rising, went to look at the lunar disc, which shone withintolerable brilliancy.
"By Jove!" said he, "it must be hot up there!"
"Without considering," replied Nicholl, "that the day lasts 360 hours!"
"And to compensate that," said Barbicane, "the nights have thesame length; and as heat is restored by radiation, theirtemperature can only be that of the planetary space."
"A pretty country, that!" exclaimed Michel. "Never mind!I wish I was there! Ah! my dear comrades, it will be rathercurious to have the earth for our moon, to see it rise on thehorizon, to recognize the shape of its continents, and to sayto oneself, `There is America, there is Europe;' then to followit when it is about to lose itself in the sun's rays! By thebye, Barbicane, have the Selenites eclipses?"
"Yes, eclipses of the sun," replied Barbicane, "when the centersof the three orbs are on a line, the earth being in the middle.But they are only partial, during which the earth, cast like ascreen upon the solar disc, allows the greater portion to be seen."
"And why," asked Nicholl, "is there no total eclipse? Does notthe cone of the shadow cast by the earth extend beyond the moon?"
"Yes, if we do not take into consideration the refractionproduced by the terrestrial atmosphere. No, if we take thatrefraction into consideration. Thus let bethe horizontal parallel, and _p_ the apparent semidiameter----"
"Oh!" said Michel. "Do speak plainly, you man of algebra!"
"Very well, replied Barbicane; "in popular language the meandistance from the moon to the earth being sixty terrestrialradii, the length of the cone of the shadow, on account ofrefraction, is reduced to less than forty-two radii.The r
esult is that when there are eclipses, the moon findsitself beyond the cone of pure shadow, and that the sun sendsher its rays, not only from its edges, but also from its center."
"Then," said Michel, in a merry tone, "why are there eclipses,when there ought not to be any?"
"Simply because the solar rays are weakened by this refraction,and the atmosphere through which they pass extinguished thegreater part of them!"
"That reason satisfies me," replied Michel. "Besides we shallsee when we get there. Now, tell me, Barbicane, do you believethat the moon is an old comet?"
"There's an idea!"
"Yes," replied Michel, with an amiable swagger, "I have a fewideas of that sort."
"But that idea does not spring from Michel," answered Nicholl.
"Well, then, I am a plagiarist."
"No doubt about it. According to the ancients, the Arcadianspretend that their ancestors inhabited the earth before the moonbecame her satellite. Starting from this fact, some scientificmen have seen in the moon a comet whose orbit will one day bringit so near to the earth that it will be held there by its attraction."
"Is there any truth in this hypothesis?" asked Michel.
"None whatever," said Barbicane, "and the proof is, that themoon has preserved no trace of the gaseous envelope which alwaysaccompanies comets."
"But," continued Nicholl, "Before becoming the earth's satellite,could not the moon, when in her perihelion, pass so near the sunas by evaporation to get rid of all those gaseous substances?"
"It is possible, friend Nicholl, but not probable."
"Why not?"
"Because-- Faith I do not know."
"Ah!" exclaimed Michel, "what hundred of volumes we might makeof all that we do not know!"
"Ah! indeed. What time is it?" asked Barbicane.
"Three o'clock," answered Nicholl.
"How time goes," said Michel, "in the conversation of scientificmen such as we are! Certainly, I feel I know too much! I feelthat I am becoming a well!"
Saying which, Michel hoisted himself to the roof of the projectile,"to observe the moon better," he pretended. During this time hiscompanions were watching through the lower glass. Nothing new to note!
When Michel Ardan came down, he went to the side scuttle; andsuddenly they heard an exclamation of surprise!
"What is it?" asked Barbicane.
The president approached the window, and saw a sort of flattenedsack floating some yards from the projectile. This objectseemed as motionless as the projectile, and was consequentlyanimated with the same ascending movement.
"What is that machine?" continued Michel Ardan. "Is it one ofthe bodies which our projectile keeps within its attraction, andwhich will accompany it to the moon?"
"What astonishes me," said Nicholl, "is that the specific weightof the body, which is certainly less than that of theprojectile, allows it to keep so perfectly on a level with it."
"Nicholl," replied Barbicane, after a moment's reflection, "I donot know what the object it, but I do know why it maintains our level."
"And why?"
"Because we are floating in space, my dear captain, and in spacebodies fall or move (which is the same thing) with equal speedwhatever be their weight or form; it is the air, which by itsresistance creates these differences in weight. When you createa vacuum in a tube, the objects you send through it, grains ofdust or grains of lead, fall with the same rapidity. Here inspace is the same cause and the same effect."
"Just so," said Nicholl, "and everything we throw out of theprojectile will accompany it until it reaches the moon."
"Ah! fools that we are!" exclaimed Michel.
"Why that expletive?" asked Barbicane.
"Because we might have filled the projectile with useful objects,books, instruments, tools, etc. We could have thrown them allout, and all would have followed in our train. But happy thought!Why cannot we walk outside like the meteor? Why cannot we launchinto space through the scuttle? What enjoyment it would be tofeel oneself thus suspended in ether, more favored than the birdswho must use their wings to keep themselves up!"
"Granted," said Barbicane, "but how to breathe?"
"Hang the air, to fail so inopportunely!"
"But if it did not fail, Michel, your density being less thanthat of the projectile, you would soon be left behind."
"Then we must remain in our car?"
"We must!"
"Ah!" exclaimed Michel, in a load voice.
"What is the matter," asked Nicholl.
"I know, I guess, what this pretended meteor is! It is noasteroid which is accompanying us! It is not a piece of a planet."
"What is it then?" asked Barbicane.
"It is our unfortunate dog! It is Diana's husband!"
Indeed, this deformed, unrecognizable object, reduced tonothing, was the body of Satellite, flattened like a bagpipewithout wind, and ever mounting, mounting!
