All Around the Moon by Jules Verne (beach books TXT) 📗
- Author: Jules Verne
Book online «All Around the Moon by Jules Verne (beach books TXT) 📗». Author Jules Verne
"Nothing is clearer, Ardan."
"You too, Captain! Then of course I must give in gracefully, and declare that the sun at noon-day is not more palpably evident than the sense of Barbican's formula."
"You asked for Algebra, you know," observed Barbican.
"Rock crystal is nothing to it!"
"The fact is, Barbican," said the Captain, who had been looking over the paper, "you have worked the thing out very well. You have the integral equation of the living forces, and I have no doubt it will give us the result sought for."
"Yes, but I should like to understand it, you know," cried Ardan: "I would give ten years of the Captain's life to understand it!"
"Listen then," said Barbican. "Half of v prime squared less v squared, is the formula giving us the half variation of the living force."
"Mac pretends he understands all that!"
"You need not be a Solomon to do it," said the Captain. "All these signs that you appear to consider so cabalistic form a language the clearest, the shortest, and the most logical, for all those who can read it."
"You pretend, Captain, that, by means of these hieroglyphics, far more incomprehensible than the sacred Ibis of the Egyptians, you can discover the velocity at which the Projectile should start?"
"Most undoubtedly," replied the Captain, "and, by the same formula I can even tell you the rate of our velocity at any particular point of our journey."
"You can?"
"I can."
"Then you're just as deep a one as our President."
"No, Ardan; not at all. The really difficult part of the question Barbican has done. That is, to make out such an equation as takes into account all the conditions of the problem. After that, it's a simple affair of Arithmetic, requiring only a knowledge of the four rules to work it out."
"Very simple," observed Ardan, who always got muddled at any kind of a difficult sum in addition.
"Captain," said Barbican, "you could have found the formulas too, if you tried."
"I don't know about that," was the Captain's reply, "but I do know that this formula is wonderfully come at."
"Now, Ardan, listen a moment," said Barbican, "and you will see what sense there is in all these letters."
"I listen," sighed Ardan with the resignation of a martyr.
"d is the distance from the centre of the Earth to the centre of the Moon, for it is from the centres that we must calculate the attractions."
"That I comprehend."
"r is the radius of the Earth."
"That I comprehend."
"m is the mass or volume of the Earth; m prime that of the Moon. We must take the mass of the two attracting bodies into consideration, since attraction is in direct proportion to their masses."
"That I comprehend."
"g is the gravity or the velocity acquired at the end of a second by a body falling towards the centre of the Earth. Clear?"
"That I comprehend."
"Now I represent by x the varying distance that separates the Projectile from the centre of the Earth, and by v prime its velocity at that distance."
"That I comprehend."
"Finally, v is its velocity when quitting our atmosphere."
"Yes," chimed in the Captain, "it is for this point, you see, that the velocity had to be calculated, because we know already that the initial velocity is exactly the three halves of the velocity when the Projectile quits the atmosphere."
"That I don't comprehend," cried the Frenchman, energetically.
"It's simple enough, however," said Barbican.
"Not so simple as a simpleton," replied the Frenchman.
"The Captain merely means," said Barbican, "that at the instant the Projectile quitted the terrestrial atmosphere it had already lost a third of its initial velocity."
"So much as a third?"
"Yes, by friction against the atmospheric layers: the quicker its motion, the greater resistance it encountered."
"That of course I admit, but your v squared and your v prime squared rattle in my head like nails in a box!"
"The usual effect of Algebra on one who is a stranger to it; to finish you, our next step is to express numerically the value of these several symbols. Now some of them are already known, and some are to be calculated."
"Hand the latter over to me," said the Captain.
"First," continued Barbican: "r, the Earth's radius is, in the latitude of Florida, about 3,921 miles. d, the distance from the centre of the Earth to the centre of the Moon is 56 terrestrial radii, which the Captain calculates to be...?"
"To be," cried M'Nicholl working rapidly with his pencil, "219,572 miles, the moment the Moon is in her perigee, or nearest point to the Earth."
"Very well," continued Barbican. "Now m prime over m, that is the ratio of the Moon's mass to that of the Earth is about the 1/81. g gravity being at Florida about 32-1/4 feet, of course g x r must be—how much, Captain?"
"38,465 miles," replied M'Nicholl.
"Now then?" asked Ardan.
MY HEAD IS SPLITTING WITH IT.
"Now then," replied Barbican, "the expression having numerical values, I am trying to find v, that is to say, the initial velocity which the Projectile must possess in order to reach the point where the two attractions neutralize each other. Here the velocity being null, v prime becomes zero, and x the required distance of this neutral point must be represented by the nine-tenths of d, the distance between the two centres."
"I have a vague kind of idea that it must be so," said Ardan.
"I shall, therefore, have the following result;" continued Barbican, figuring up; "x being nine-tenths of d, and v prime being zero, my formula becomes:—
The Captain read it off rapidly.
"Right! that's correct!" he cried.
"You think so?" asked Barbican.
"As true as Euclid!" exclaimed M'Nicholl.
"Wonderful fellows," murmured the Frenchman, smiling with admiration.
"You understand now, Ardan, don't you?" asked Barbican.
"Don't I though?" exclaimed Ardan, "why my head is splitting with it!"
"Therefore," continued Barbican,
"And now," exclaimed M'Nicholl, sharpening his pencil; "in order to obtain the velocity of the Projectile when leaving the atmosphere, we have only to make a slight calculation."
The Captain, who before clerking on a Mississippi steamboat had been professor of Mathematics in an Indiana university, felt quite at home at the work. He rained figures from his pencil with a velocity that would have made Marston stare. Page after page was filled with his multiplications and divisions, while Barbican looked quietly on, and Ardan impatiently stroked his head and ears to keep down a rising head-ache.
"Well?" at last asked Barbican, seeing the Captain stop and throw a somewhat hasty glance over his work.
"Well," answered M'Nicholl slowly but confidently, "the calculation is made, I think correctly; and v, that is, the velocity of the Projectile when quitting the atmosphere, sufficient to carry it to the neutral point, should be at least ..."
"How much?" asked Barbican, eagerly.
"Should be at least 11,972 yards the first second."
"What!" cried Barbican, jumping off his seat. "How much did you say?"
"11,972 yards the first second it quits the atmosphere."
"Oh, malediction!" cried Barbican, with a gesture of terrible despair.
"What's the matter?" asked Ardan, very much surprised.
"Enough is the matter!" answered Barbican excitedly. "This velocity having been diminished by a third, our initial velocity should have been at least ..."
"17,958 yards the first second!" cried M'Nicholl, rapidly flourishing his pencil.
"But the Cambridge Observatory having declared that 12,000 yards the first second were sufficient, our Projectile started with no greater velocity!"
"Well?" asked M'Nicholl.
"Well, such a velocity will never do!"
"How??""How!!" cried the Captain and Ardan in one voice.
"We can never reach the neutral point!"
"Thunder and lightning"
"Fire and Fury!"
"We can't get even halfway!"
"Heaven and Earth!"
"Mille noms d'un boulet!" cried Ardan, wildly gesticulating.
"And we shall fall back to the Earth!"
"Oh!"
"Ah!"
They could say no more. This fearful revelation took them like a stroke of apoplexy.
CHAPTER V. THE COLDS OF SPACE.How could they imagine that the Observatory men had committed such a blunder? Barbican would not believe it possible. He made the Captain go over his calculation again and again; but no flaw was to be found in it. He himself carefully examined it, figure after figure, but he could find nothing wrong. They both took up the formula and subjected it to the strongest tests; but it was invulnerable. There was no denying the fact. The Cambridge professors had undoubtedly blundered in saying that an initial velocity of 12,000 yards a second would be enough to carry them to the neutral point. A velocity of nearly 18,000 yards would be the very lowest required for such a purpose. They had simply forgotten to allow a third for friction.
The three friends kept profound silence for some time. Breakfast now was the last thing thought of. Barbican, with teeth grating, fingers clutching, and eye-brows closely contracting, gazed grimly through the window. The Captain, as a last resource, once more examined his calculations, earnestly hoping to find a figure wrong. Ardan could neither sit, stand nor lie still for a second, though he tried all three. His silence, of course, did not last long.
"Ha! ha! ha!" he laughed bitterly. "Precious scientific men! Villainous old hombogues! The whole set not worth a straw! I hope to gracious, since we must fall, that we shall drop down plumb on Cambridge Observatory, and not leave a single one of the miserable old women, called professors, alive in the premises!"
A certain expression in Ardan's angry exclamation had struck the Captain like a shot, and set his temples throbbing violently.
"Must fall!" he exclaimed, starting up suddenly. "Let us see about that! It is now seven o'clock in the morning. We must have, therefore, been at least thirty-two hours on the road, and more than half of our passage is already made. If we are going to fall at all, we must be falling now! I'm certain we're not, but, Barbican, you have to find it out!"
Barbican caught the idea like lightning, and, seizing a compass, he began through the floor window to measure the visual angle of the distant Earth. The apparent immobility of the Projectile allowed him to do this with great exactness. Then laying aside the instrument, and wiping off the thick drops of sweat that bedewed his forehead, he began jotting down some figures on a piece of paper. The Captain looked on with keen interest; he knew very well that Barbican was calculating their distance from the Earth by the apparent measure of the terrestrial diameter, and he eyed him anxiously.
Pretty soon his friends saw a color stealing into Barbican's pale face, and a triumphant light glittering in his eye.
"No, my brave boys!" he exclaimed at last throwing down his pencil, "we're not falling! Far from it, we are at present more than 150 thousand miles from the Earth!"
"Hurrah!""Bravo!" cried M'Nicholl and Ardan, in a breath.
"We have passed the point where we should have stopped if we had had no more initial velocity than the Cambridge men allowed us!"
"Hurrah! hurrah!"
"Bravo, Bravissimo!"
"And we're still going up!"
"Glory, glory, hallelujah!" sang M'Nicholl, in the highest excitement.
"Vive ce cher Barbican!" cried Ardan, bursting into French as usual whenever his feelings had the better of him.
"Of course we're marching on!" continued M'Nicholl, "and I know the reason why, too. Those 400,000 pounds of gun-cotton gave us greater initial velocity than we had expected!"
"You're right, Captain!" added Barbican; "besides, you must not forget that, by getting rid of the water, the Projectile was relieved of considerable weight!"
"Correct again!" cried the Captain. "I had not thought of that!"
"Therefore, my brave boys," continued Barbican, with some excitement; "away with melancholy! We're all right!"
"Yes; everything is lovely and the goose hangs high!" cried the Captain, who on grand occasions was not above a little slang.
"Talking of goose reminds me of breakfast," cried Ardan; "I assure you, my fright has not taken away my appetite!"
"Yes," continued Barbican. "Captain, you're quite right. Our initial velocity very fortunately was
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