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Chapter XII. Orographic Details
The course taken by the projectile, as we have before remarked,
was bearing it toward the moon’s northern hemisphere. The
travelers were far from the central point which they would have
struck, had their course not been subject to an irremediable
deviation. It was past midnight; and Barbicane then estimated the
distance at seven hundred and fifty miles, which was a little
greater than the length of the lunar radius, and which would
diminish as it advanced nearer to the North Pole. The projectile
was then not at the altitude of the equator; but across the tenth
parallel, and from that latitude, carefully taken on the map to the
pole, Barbicane and his two companions were able to observe the
moon under the most favorable conditions. Indeed, by means of
glasses, the above-named distance was reduced to little more than
fourteen miles. The telescope of the Rocky Mountains brought the
moon much nearer; but the terrestrial atmosphere singularly
lessened its power. Thus Barbicane, posted in his projectile, with
the glasses to his eyes, could seize upon details which were almost
imperceptible to earthly observers.
“My friends,” said the president, in a serious
voice, “I do not know whither we are going; I do not know if
we shall ever see the terrestrial globe again. Nevertheless, let us
proceed as if our work would one day by useful to our fellow-men.
Let us keep our minds free from every other consideration. We are
astronomers; and this projectile is a room in the Cambridge
University, carried into space. Let us make our
observations!”
This said, work was begun with great exactness; and they
faithfully reproduced the different aspects of the moon, at the
different distances which the projectile reached.
At the time that the projectile was as high as the tenth
parallel, north latitude, it seemed rigidly to follow the twentieth
degree, east longitude. We must here make one important remark with
regard to the map by which they were taking observations. In the
selenographical maps where, on account of the reversing of the
objects by the glasses, the south is above and the north below, it
would seem natural that, on account of that inversion, the east
should be to the left hand, and the west to the right. But it is
not so. If the map were turned upside down, showing the moon as we
see her, the east would be to the left, and the west to the right,
contrary to that which exists on terrestrial maps. The following is
the reason of this anomaly. Observers in the northern hemisphere
(say in Europe) see the moon in the south— according to them.
When they take observations, they turn their backs to the north,
the reverse position to that which they occupy when they study a
terrestrial map. As they turn their backs to the north, the east is
on their left, and the west to their right. To observers in the
southern hemisphere (Patagonia for example), the moon’s west
would be quite to their left, and the east to their right, as the
south is behind them. Such is the reason of the apparent reversing
of these two cardinal points, and we must bear it in mind in order
to be able to follow President Barbicane’s observations.
With the help of Boeer and Moedler’s Mappa Selenographica,
the travelers were able at once to recognize that portion of the
disc enclosed within the field of their glasses.
“What are we looking at, at this moment?” asked
Michel.
“At the northern part of the ‘Sea of
Clouds,’” answered Barbicane. “We are too far off
to recognize its nature. Are these plains composed of arid sand, as
the first astronomer maintained? Or are they nothing but immense
forests, according to M. Warren de la Rue’s opinion, who
gives the moon an atmosphere, though a very low and a very dense
one? That we shall know by and by. We must affirm nothing until we
are in a position to do so.”
This “Sea of Clouds” is rather doubtfully marked out
upon the maps. It is supposed that these vast plains are strewn
with blocks of lava from the neighboring volcanoes on its right,
Ptolemy, Purbach, Arzachel. But the projectile was advancing, and
sensibly nearing it. Soon there appeared the heights which bound
this sea at this northern limit. Before them rose a mountain
radiant with beauty, the top of which seemed lost in an eruption of
solar rays.
“That is—?” asked Michel.
“Copernicus,” replied Barbicane.
“Let us see Copernicus.”
This mount, situated in 9° north latitude and 20° east
longitude, rose to a height of 10,600 feet above the surface of the
moon. It is quite visible from the earth; and astronomers can study
it with ease, particularly during the phase between the last
quarter and the new moon, because then the shadows are thrown
lengthways from east to west, allowing them to measure the
heights.
This Copernicus forms the most important of the radiating
system, situated in the southern hemisphere, according to Tycho
Brahe. It rises isolated like a gigantic lighthouse on that portion
of the “Sea of Clouds,” which is bounded by the
“Sea of Tempests,” thus lighting by its splendid rays
two oceans at a time. It was a sight without an equal, those long
luminous trains, so dazzling in the full moon, and which, passing
the boundary chain on the north, extends to the “Sea of
Rains.” At one o’clock of the terrestrial morning, the
projectile, like a balloon borne into space, overlooked the top of
this superb mount. Barbicane could recognize perfectly its chief
features. Copernicus is comprised in the series of ringed mountains
of the first order, in the division of great circles. Like Kepler
and Aristarchus, which overlook the “Ocean of
Tempests,” sometimes it appeared like a brilliant point
through the cloudy light, and was taken for a volcano in activity.
But it is only an extinct one— like all on that side of the
moon. Its circumference showed a diameter of about twenty-two
leagues. The glasses discovered traces of stratification produced
by successive eruptions, and the neighborhood was strewn with
volcanic remains which still choked some of the craters.
“There exist,” said Barbicane, “several kinds
of circles on the surface of the moon, and it is easy to see that
Copernicus belongs to the radiating class. If we were nearer, we
should see the cones bristling on the inside, which in former times
were so many fiery mouths. A curious arrangement, and one without
an exception on the lunar disc, is that the interior surface of
these circles is the reverse of the exterior, and contrary to the
form taken by terrestrial craters. It follows, then, that the
general curve of the bottom of these circles gives a sphere of a
smaller diameter than that of the moon.”
“And why this peculiar disposition?” asked
Nicholl.
“We do not know,” replied Barbicane.
“What splendid radiation!” said Michel. “One
could hardly see a finer spectacle, I think.”
“What would you say, then,” replied Barbicane,
“if chance should bear us toward the southern
hemisphere?”
“Well, I should say that it was still more
beautiful,” retorted Michel Ardan.
At this moment the projectile hung perpendicularly over the
circle. The circumference of Copernicus formed almost a perfect
circle, and its steep escarpments were clearly defined. They could
even distinguish a second ringed enclosure. Around spread a grayish
plain, of a wild aspect, on which every relief was marked in
yellow. At the bottom of the circle, as if enclosed in a jewel
case, sparkled for one instant two or three eruptive cones, like
enormous dazzling gems. Toward the north the escarpments were
lowered by a depression which would probably have given access to
the interior of the crater.
In passing over the surrounding plains, Barbicane noticed a
great number of less important mountains; and among others a little
ringed one called Guy Lussac, the breadth of which measured twelve
miles.
Toward the south, the plain was very flat, without one
elevation, without one projection. Toward the north, on the
contrary, till where it was bounded by the “Sea of
Storms,” it resembled a liquid surface agitated by a storm,
of which the hills and hollows formed a succession of waves
suddenly congealed. Over the whole of this, and in all directions,
lay the luminous lines, all converging to the summit of
Copernicus.
The travelers discussed the origin of these strange rays; but
they could not determine their nature any more than terrestrial
observers.
“But why,” said Nicholl, “should not these
rays be simply spurs of mountains which reflect more vividly the
light of the sun?”
“No,” replied Barbicane; “if it was so, under
certain conditions of the moon, these ridges would cast shadows,
and they do not cast any.”
And indeed, these rays only appeared when the orb of day was in
opposition to the moon, and disappeared as soon as its rays became
oblique.
“But how have they endeavored to explain these lines of
light?” asked Michel; “for I cannot believe that
savants would ever be stranded for want of an
explanation.”
“Yes,” replied Barbicane; “Herschel has put
forward an opinion, but he did not venture to affirm it.”
“Never mind. What was the opinion?”
“He thought that these rays might be streams of cooled
lava which shone when the sun beat straight upon them. It may be
so; but nothing can be less certain1. Besides, if we pass nearer to
Tycho, we shall be in a better position to find out the cause of
this radiation.”
“Do you know, my friends, what that plain, seen from the
height we are at, resembles?” said Michel.
“No,” replied Nicholl.
“Very well; with all those pieces of lava lengthened like
rockets, it resembles an immense game of spelikans thrown pellmell.
There wants but the hook to pull them out one by one.”
“Do be serious,” said Barbicane.
“Well, let us be serious,” replied Michel quietly;
“and instead of spelikans, let us put bones. This plain,
would then be nothing but an immense cemetery, on which would
repose the mortal remains of thousands of extinct generations. Do
you prefer that high-flown comparison?”
“One is as good as the other,” retorted
Barbicane.
“My word, you are difficult to please,” answered
Michel.
“My worthy friend,” continued the matter-of-fact
Barbicane, “it matters but little what it resembles, when we
do not know what it is.”
“Well answered,” exclaimed Michel. “That will
teach me to reason with savants.”
But the projectile continued to advance with almost uniform
speed around the lunar disc. The travelers, we may easily imagine,
did not dream of taking a moment’s rest. Every minute changed
the landscape which fled from beneath their gaze. About half past
one o’clock in the morning, they caught a glimpse of the tops
of another mountain. Barbicane, consulting his map, recognized
Eratosthenes.
It was a ringed mountain nine thousand feet high, and one of
those circles so numerous on this satellite. With regard to this,
Barbicane related Kepler’s singular opinion on the formation
of circles. According to that celebrated mathematician, these
crater-like cavities had been dug by the hand of man.
“For what purpose?” asked Nicholl.
“For a very natural one,” replied Barbicane.
“The Selenites might have undertaken these immense works and
dug these enormous holes for a refuge and shield from the solar
rays which beat upon them during fifteen consecutive
days.”
“The Selenites are not fools,” said Michel.
“A singular idea,” replied Nicholl; “but it is
probable that Kepler did not know the true dimensions of these
circles, for the digging of them would have been the work of giants
quite impossible for the Selenites.”
“Why? if weight on the moon’s surface is six times
less than on the earth?” said Michel.
“But if the Selenites are six times smaller?”
retorted Nicholl.
“And if there are no Selenites?” added
Barbicane.
This put an end to the discussion.
Soon Eratosthenes disappeared under the horizon without the
projectile being sufficiently near to allow close observation. This
mountain separated the Apennines from the Carpathians. In the lunar
orography they have discerned some chains of mountains, which are
chiefly distributed over the northern hemisphere. Some, however,
occupy certain portions of the southern hemisphere also.
About two o’clock in the morning Barbicane found that they
were above the twentieth lunar parallel. The distance of the
projectile from the moon was not more than six hundred miles.
Barbicane, now perceiving that the projectile was steadily
approaching the lunar disc, did not despair; if not of reaching
her, at least of discovering the secrets of her
configuration.
1The rays that they refer to are in fact ejecta from the creation of the crater by the impact of a meteor.
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