"Not as simple as I am," retorted Michel.
"That means, that when our projectile reached the limits of the terrestrial atmosphere it had already lost one-third of its initiatory speed."
"As much as that?"
"Yes, my friend; merely by friction against the atmospheric strata.
You understand that the faster it goes the more resistance it meets with from the air."
"That I admit," answered Michel; "and I understand it, although your x"s and zero"s, and algebraic formula, are rattling in my head like nails in a bag."
"First effects of algebra," replied Barbicane; "and now, to finish, we are going to prove the given number of these different expressions, that is, work out their value."
"Finish me!" replied Michel.
Barbicane took the paper, and began to make his calculations with great rapidity. Nicholl looked over and greedily read the work as it proceeded.
"That"s it! that"s it!" at last he cried.
"Is it clear?" asked Barbicane.
"It is written in letters of fire," said Nicholl.
"Wonderful fellows!" muttered Ardan.
"Do you understand it at last?" asked Barbicane.
"Do I understand it?" cried Ardan; "my head is splitting with it."
"And now," said Nicholl, "to find out the speed of the projectile when it leaves the atmosphere, we have only to calculate that."
The captain, as a practical man equal to all difficulties, began to write with frightful rapidity. Divisions and multiplications grew under his fingers; the figures were like hail on the white page.
Barbicane watched him, while Michel Ardan nursed a growing headache with both hands.
"Very well?" asked Barbicane, after some minutes" silence.
"Well!" replied Nicholl; every calculation made, _v_ zero, that is to say, the speed necessary for the projectile on leaving the atmosphere, to enable it to reach the equal point of attraction, ought to be----"
"Yes?" said Barbicane.
"Twelve thousand yards."
"What!" exclaimed Barbicane, starting; "you say----"
"Twelve thousand yards."
"The devil!" cried the president, making a gesture of despair.
"What is the matter?" asked Michel Ardan, much surprised.
"What is the matter! why, if at this moment our speed had already diminished one-third by friction, the initiatory speed ought to have been----"
"Seventeen thousand yards."
"And the Cambridge Observatory declared that twelve thousand yards was enough at starting; and our projectile, which only started with that speed----"
"Well?" asked Nicholl.
"Well, it will not be enough."
"Good."
"We shall not be able to reach the neutral point."
"The deuce!"
"We shall not even get halfway."
"In the name of the projectile!" exclaimed Michel Ardan, jumping as if it was already on the point of striking the terrestrial globe.
"And we shall fall back upon the earth!"
CHAPTER V
THE COLD OF s.p.a.cE
This revelation came like a thunderbolt. Who could have expected such an error in calculation? Barbicane would not believe it. Nicholl revised his figures: they were exact.
As to the formula which had determined them, they could not suspect its truth; it was evident that an initiatory velocity of seventeen thousand yards in the first second was necessary to enable them to reach the neutral point.
The three friends looked at each other silently. There was no thought of breakfast. Barbicane, with clenched teeth, knitted brows, and hands clasped convulsively, was watching through the window. Nicholl had crossed his arms, and was examining his calculations. Michel Ardan was muttering:
"That is just like these scientific men: they never do anything else.
I would give twenty pistoles if we could fall upon the Cambridge Observatory and crush it, together with the whole lot of dabblers in figures which it contains."
Suddenly a thought struck the captain, which he at once communicated to Barbicane.
"Ah!" said he; "it is seven o"clock in the morning; we have already been gone thirty-two hours; more than half our pa.s.sage is over, and we are not falling that I am aware of."
Barbicane did not answer, but after a rapid glance at the captain, took a pair of compa.s.ses wherewith to measure the angular distance of the terrestrial globe; then from the lower window he took an exact observation, and noticed that the projectile was apparently stationary. Then rising and wiping his forehead, on which large drops of perspiration were standing, he put some figures on paper. Nicholl understood that the president was deducting from the terrestrial diameter the projectile"s distance from the earth. He watched him anxiously.
"No," exclaimed Barbicane, after some moments, "no, we are not falling! no, we are already more than 50,000 leagues from the earth.
We have pa.s.sed the point at which the projectile would have stopped if its speed had only been 12,000 yards at starting. We are still going up."
"That is evident," replied Nicholl; "and we must conclude that our initial speed, under the power of the 400,000 pounds of gun-cotton, must have exceeded the required 12,000 yards.