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Chapter XV - Hyperbola or Parabola
We may, perhaps, be astonished to find Barbicane and his
companions so little occupied with the future reserved for them
in their metal prison which was bearing them through the
infinity of space. Instead of asking where they were going,
they passed their time making experiments, as if they had been
quietly installed in their own study.
We might answer that men so strong-minded were above such
anxieties-- that they did not trouble themselves about such
trifles-- and that they had something else to do than to
occupy their minds with the future.
The truth was that they were not masters of their projectile;
they could neither check its course, nor alter its direction.
A sailor can change the head of his ship as he pleases; an
aeronaut can give a vertical motion to his balloon. They, on
the contrary, had no power over their vehicle. Every maneuver
was forbidden. Hence the inclination to let things alone, or as
the sailors say, "let her run."
Where did they find themselves at this moment, at eight o'clock in
the morning of the day called upon the earth the 6th of December?
Very certainly in the neighborhood of the moon, and even near
enough for her to look to them like an enormous black screen upon
the firmament. As to the distance which separated them, it was
impossible to estimate it. The projectile, held by some
unaccountable force, had been within four miles of grazing the
satellite's north pole.
But since entering the cone of shadow these last two hours, had
the distance increased or diminished? Every point of mark was
wanting by which to estimate both the direction and the speed of
the projectile.
Perhaps it was rapidly leaving the disc, so that it would soon
quit the pure shadow. Perhaps, again, on the other hand, it
might be nearing it so much that in a short time it might strike
some high point on the invisible hemisphere, which would doubtlessly
have ended the journey much to the detriment of the travelers.
A discussion arose on this subject, and Michel Ardan, always
ready with an explanation, gave it as his opinion that the
projectile, held by the lunar attraction, would end by falling
on the surface of the terrestrial globe like an aerolite.
"First of all, my friend," answered Barbicane, "every aerolite
does not fall to the earth; it is only a small proportion which
do so; and if we had passed into an aerolite, it does not necessarily
follow that we should ever reach the surface of the moon."
"But how if we get near enough?" replied Michel.
"Pure mistake," replied Barbicane. "Have you not seen shooting
stars rush through the sky by thousands at certain seasons?"
"Yes."
"Well, these stars, or rather corpuscles, only shine when they
are heated by gliding over the atmospheric layers. Now, if
they enter the atmosphere, they pass at least within forty
miles of the earth, but they seldom fall upon it. The same with
our projectile. It may approach very near to the moon, and not
yet fall upon it."
"But then," asked Michel, "I shall be curious to know how our
erring vehicle will act in space?"
"I see but two hypotheses," replied Barbicane, after some
moments' reflection.
"What are they?"
"The projectile has the choice between two mathematical curves,
and it will follow one or the other according to the speed with
which it is animated, and which at this moment I cannot estimate."
"Yes," said Nicholl, "it will follow either a parabola or
a hyperbola."
"Just so," replied Barbicane. "With a certain speed it will
assume the parabola, and with a greater the hyperbola."
"I like those grand words," exclaimed Michel Ardan; "one knows
directly what they mean. And pray what is your parabola, if
you please?"
"My friend," answered the captain, "the parabola is a curve of
the second order, the result of the section of a cone
intersected by a plane parallel to one of the sides."
"Ah! ah!" said Michel, in a satisfied tone.
"It is very nearly," continued Nicholl, "the course described by
a bomb launched from a mortar."
"Perfect! And the hyperbola?"
"The hyperbola, Michel, is a curve of the second order, produced
by the intersection of a conic surface and a plane parallel to
its axis, and constitutes two branches separated one from the other,
both tending indefinitely in the two directions."
"Is it possible!" exclaimed Michel Ardan in a serious tone, as
if they had told him of some serious event. "What I particularly
like in your definition of the hyperbola (I was going to say
hyperblague) is that it is still more obscure than the word you
pretend to define."
Nicholl and Barbicane cared little for Michel Ardan's fun.
They were deep in a scientific discussion. What curve would
the projectile follow? was their hobby. One maintained the
hyperbola, the other the parabola. They gave each other reasons
bristling with _x_. Their arguments were couched in language
which made Michel jump. The discussion was hot, and neither
would give up his chosen curve to his adversary.
This scientific dispute lasted so long that it made Michel
very impatient.
"Now, gentlemen cosines, will you cease to throw parabolas and
hyperbolas at each other's heads? I want to understand the only
interesting question in the whole affair. We shall follow one
or the other of these curves? Good. But where will they lead
us to?"
"Nowhere," replied Nicholl.
"How, nowhere?"
"Evidently," said Barbicane, "they are open curves, which may be
prolonged indefinitely."
"Ah, savants!" cried Michel; "and what are either the one or the
other to us from the moment we know that they equally lead us
into infinite space?"
Barbicane and Nicholl could not forbear smiling. They had just
been creating "art for art's sake." Never had so idle a question
been raised at such an inopportune moment. The sinister truth
remained that, whether hyperbolically or parabolically borne away,
the projectile would never again meet either the earth or the moon.
What would become of these bold travelers in the immediate future?
If they did not die of hunger, if they did not die of thirst,
in some days, when the gas failed, they would die from want of air,
unless the cold had killed them first. Still, important as it was
to economize the gas, the excessive lowness of the surrounding
temperature obliged them to consume a certain quantity.
Strictly speaking, they could do without its _light_, but not
without its _heat_. Fortunately the caloric generated by Reiset's
and Regnaut's apparatus raised the temperature of the interior
of the projectile a little, and without much expenditure they
were able to keep it bearable.
But observations had now become very difficult. the dampness of
the projectile was condensed on the windows and congealed immediately.
This cloudiness had to be dispersed continually. In any case
they might hope to be able to discover some phenomena of the
highest interest.
But up to this time the disc remained dumb and dark. It did not
answer the multiplicity of questions put by these ardent minds;
a matter which drew this reflection from Michel, apparently a
just one:
"If ever we begin this journey over again, we shall do well to
choose the time when the moon is at the full."
"Certainly," said Nicholl, "that circumstance will be more favorable.
I allow that the moon, immersed in the sun's rays, will not be
visible during the transit, but instead we should see the earth,
which would be full. And what is more, if we were drawn round the
moon, as at this moment, we should at least have the advantage of
seeing the invisible part of her disc magnificently lit."
"Well said, Nicholl," replied Michel Ardan. "What do you
think, Barbicane?"
"I think this," answered the grave president: "If ever we begin
this journey again, we shall start at the same time and under
the same conditions. Suppose we had attained our end, would it
not have been better to have found continents in broad daylight
than a country plunged in utter darkness? Would not our first
installation have been made under better circumstances?
Yes, evidently. As to the invisible side, we could have visited
it in our exploring expeditions on the lunar globe. So that the
time of the full moon was well chosen. But we ought to have
arrived at the end; and in order to have so arrived, we ought
to have suffered no deviation on the road."
"I have nothing to say to that," answered Michel Ardan.
"Here is, however, a good opportunity lost of observing the
other side of the moon."
But the projectile was now describing in the shadow that
incalculable course which no sight-mark would allow them
to ascertain. Had its direction been altered, either by the
influence of the lunar attraction, or by the action of some
unknown star? Barbicane could not say. But a change had taken
place in the relative position of the vehicle; and Barbicane
verified it about four in the morning.
The change consisted in this, that the base of the projectile
had turned toward the moon's surface, and was so held by a
perpendicular passing through its axis. The attraction, that is
to say the weight, had brought about this alteration. The heaviest
part of the projectile inclined toward the invisible disc as if it
would fall upon it.
Was it falling? Were the travelers attaining that much desired end?
No. And the observation of a sign-point, quite inexplicable in
itself, showed Barbicane that his projectile was not nearing the
moon, and that it had shifted by following an almost concentric curve.
This point of mark was a luminous brightness, which Nicholl
sighted suddenly, on the limit of the horizon formed by the
black disc. This point could not be confounded with a star.
It was a reddish incandescence which increased by degrees, a
decided proof that the projectile was shifting toward it and
not falling normally on the surface of the moon.
"A volcano! it is a volcano in action!" cried Nicholl; "a
disemboweling of the interior fires of the moon! That world is
not quite extinguished."
"Yes, an eruption," replied Barbicane, who was carefully
studying the phenomenon through his night glass. "What should
it be, if not a volcano?"
"But, then," said Michel Ardan, "in order to maintain that
combustion, there must be air. So the atmosphere does surround
that part of the moon."
"Perhaps so," replied Barbicane, "but not necessarily.
The volcano, by the decomposition of certain substances, can
provide its own oxygen, and thus throw flames into space. It seems
to me that the deflagration, by the intense brilliancy of the
substances in combustion, is produced in pure oxygen. We must
not be in a hurry to proclaim the existence of a lunar atmosphere."
The fiery mountain must have been situated about the 45@ south
latitude on the invisible part of the disc; but, to Barbicane's
great displeasure, the curve which the projectile was describing
was taking it far from the point indicated by the eruption.
Thus he could not determine its nature exactly. Half an hour
after being sighted, this luminous point had disappeared behind
the dark horizon; but the verification of this phenomenon was
of considerable consequence in their selenographic studies.
It proved that all heat had not yet disappeared from the bowels
of this globe; and where heat exists, who can affirm that the
vegetable kingdom, nay, even the animal kingdom itself, has not
up to this time resisted all destructive influences? The existence
of this volcano in eruption, unmistakably seen by these earthly
savants, would doubtless give rise to many theories favorable
to the grave question of the habitability of the moon.
Barbicane allowed himself to be carried away by these reflections.
He forgot himself in a deep reverie in which the mysterious
destiny of the lunar world was uppermost. He was seeking to
combine together the facts observed up to that time, when a new
incident recalled him briskly to reality. This incident was more
than a cosmical phenomenon; it was a threatened danger, the
consequence of which might be disastrous in the extreme.
Suddenly, in the midst of the ether, in the profound darkness, an
enormous mass appeared. It was like a moon, but an incandescent
moon whose brilliancy was all the more intolerable as it cut
sharply on the frightful darkness of space. This mass, of a
circular form, threw a light which filled the projectile.
The forms of Barbicane, Nicholl, and Michel Ardan, bathed in
its white sheets, assumed that livid spectral appearance which
physicians produce with the fictitious light of alcohol
impregnated with salt.
"By Jove!" cried Michel Ardan, "we are hideous. What is that
ill-conditioned moon?"
"A meteor," replied Barbicane.
"A meteor burning in space?"
"Yes."
This shooting globe suddenly appearing in shadow at a distance
of at most 200 miles, ought, according to Barbicane, to have a
diameter of 2,000 yards. It advanced at a speed of about one
mile and a half per second. It cut the projectile's path and
must reach it in some minutes. As it approached it grew to
enormous proportions.
Imagine, if possible, the situation of the travelers! It is
impossible to describe it. In spite of their courage, their
_sang-froid_, their carelessness of danger, they were mute,
motionless with stiffened limbs, a prey to frightful terror.
Their projectile, the course of which they could not alter, was
rushing straight on this ignited mass, more intense than the
open mouth of an oven. It seemed as though they were being
precipitated toward an abyss of fire.
Barbicane had seized the hands of his two companions, and all
three looked through their half-open eyelids upon that asteroid
heated to a white heat. If thought was not destroyed within
them, if their brains still worked amid all this awe, they must
have given themselves up for lost.
Two minutes after the sudden appearance of the meteor (to them
two centuries of anguish) the projectile seemed almost about to
strike it, when the globe of fire burst like a bomb, but without
making any noise in that void where sound, which is but the
agitation of the layers of air, could not be generated.
Nicholl uttered a cry, and he and his companions rushed to
the scuttle. What a sight! What pen can describe it?
What palette is rich enough in colors to reproduce so magnificent
a spectacle?
It was like the opening of a crater, like the scattering of an
immense conflagration. Thousands of luminous fragments lit up
and irradiated space with their fires. Every size, every color,
was there intermingled. There were rays of yellow and pale
yellow, red, green, gray-- a crown of fireworks of all colors.
Of the enormous and much-dreaded globe there remained nothing
but these fragments carried in all directions, now become
asteroids in their turn, some flaming like a sword, some
surrounded by a whitish cloud, and others leaving behind them
trains of brilliant cosmical dust.
These incandescent blocks crossed and struck each other,
scattering still smaller fragments, some of which struck
the projectile. Its left scuttle was even cracked by a
violent shock. It seemed to be floating amid a hail of
howitzer shells, the smallest of which might destroy
it instantly.
The light which saturated the ether was so wonderfully intense,
that Michel, drawing Barbicane and Nicholl to his window,
exclaimed, "The invisible moon, visible at last!"
And through a luminous emanation, which lasted some seconds, the
whole three caught a glimpse of that mysterious disc which the eye
of man now saw for the first time. What could they distinguish
at a distance which they could not estimate? Some lengthened
bands along the disc, real clouds formed in the midst of a very
confined atmosphere, from which emerged not only all the mountains,
but also projections of less importance; its circles, its yawning
craters, as capriciously placed as on the visible surface.
Then immense spaces, no longer arid plains, but real seas, oceans,
widely distributed, reflecting on their liquid surface all the
dazzling magic of the fires of space; and, lastly, on the surface
of the continents, large dark masses, looking like immense forests
under the rapid illumination of a brilliance.
Was it an illusion, a mistake, an optical illusion? Could they
give a scientific assent to an observation so superficially obtained?
Dared they pronounce upon the question of its habitability after
so slight a glimpse of the invisible disc?
But the lightnings in space subsided by degrees; its accidental
brilliancy died away; the asteroids dispersed in different
directions and were extinguished in the distance.
The ether returned to its accustomed darkness; the stars, eclipsed
for a moment, again twinkled in the firmament, and the disc, so
hastily discerned, was again buried in impenetrable night.
Content of Chapter XV - Hyperbola or Parabola [Jules Verne's novel: A trip around the Moon]
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