"Then," said Johnson, "according to you, Doctor, this change is impossible?"
"Impossible!"
"And if it should take place?"
"If it did, the equator would be frozen in twenty-four hours!"
"Good! if it were to take place now," said Bell, "people would as likely as not say we had never gone to the Pole."
"Calm yourself, Bell. To return to the immobility of the terrestrial axis, the following is the result: if we were to spend a winter here, we should see the stars describing a circle about us. As for the sun, the day of the vernal equinox, March 23d, it would appear to us (I take no account of refraction) exactly cut in two by the horizon, and would rise gradually in longer and longer curves; but here it is remarkable that when it has once risen it sets no more; it is visible for six months. Then its disk touches the horizon again at the autumnal equinox, September 22d, and as soon as it is set, it is seen no more again all winter."
"You were speaking just now of the flattening of the earth at the poles," said Johnson; "be good enough to explain that, Doctor."
"I will. Since the earth was fluid when first created, you understand that its rotary movement would try to drive part of the mobile ma.s.s to the equator, where the centrifugal force was greater. If the earth had been motionless, it would have remained a perfect sphere; but in consequence of the phenomenon I have just described, it has an ellipsoidal form, and points at the pole are nearer the centre of the earth than points at the equator by about five leagues."
"So," said Johnson, "if our captain wanted to take us to the centre of the earth, we should have five leagues less to go?"
"Exactly, my friend."
"Well, Captain, it"s so much gained! We ought to avail ourselves of it."
But Hatteras did not answer. Evidently he had lost all interest in the conversation, or perhaps he was listening without hearing.
"Well," answered the doctor, "according to certain scientific men, it would be worth while to try this expedition."
"What! really?" exclaimed Johnson.
"But let me finish," answered the doctor. "I will tell you. I must first tell you this flattening of the poles is the cause of the precession of the equinoxes; that is to say, why every year the vernal equinox comes a day sooner than it would if the earth were perfectly round. This comes from the attraction of the sun operating in a different way on the heaped-up land of the equator, which then experiences a retrograde movement. Subsequently it displaces this Pole a little, as I just said. But, independently of this effect, this flattening ought to have a more curious and more personal effect, which we should perceive if we had mathematical sensibility."
"What do you mean?" asked Bell.
"I mean that we are heavier here than at Liverpool."
"Heavier?"
"Yes; ourselves, the dogs, our guns, and instruments!"
"Is it possible?"
"Certainly, and for two reasons: the first is, that we are nearer the centre of the globe, which consequently attracts us more strongly, and this force of gravitation is nothing but weight; the second is, the rotary force, which is nothing at the pole, is very marked at the equator, and objects there have a tendency to fly from the earth: they are less heavy."
"What!" exclaimed Johnson, seriously; "have we not the same weight everywhere?"
"No, Johnson; according to Newton"s law, bodies attract one another directly as their ma.s.ses, and inversely to the square of their distances. Here I weigh more, because I am nearer the centre of attraction; and on another planet I should weigh more or less according to the ma.s.s of the planet."
"What!" said Bell, "in the moon--"
"In the moon my weight, which is two hundred pounds at Liverpool, would be only thirty-two pounds."
"And in the sun?"
"O, in the sun I should weigh more than five thousand pounds!"
"Heavens!" said Bell; "you"d need a derrick to move your legs."
"Probably," answered the doctor, laughing at Bell"s amazement; "but here the difference is imperceptible, and by an equal effort of the muscles Bell would leap as high as on the docks at Liverpool."
"Yes, but in the sun?" urged Bell.
"My friend," answered the doctor, "the upshot of it all is that we are well off where we are, and need not want to go elsewhere."
"You said just now," resumed Altamont, "that perhaps it would be worth while to make a journey to the centre of the world; has such an undertaking ever been thought of?"
"Yes, and this is all I"m going to say about the Pole. There is no point in the world which has given rise to more chimeras and hypotheses. The ancients, in their ignorance, placed the garden of the Hesperides there. In the Middle Ages it was supposed that the earth was upheld on axles placed at the poles, on which it revolved; but when comets were seen moving freely, that idea had to be given up.
Later, there was a French astronomer, Bailly, who said that the lost people mentioned by Plato, the Atlantides, lived here. Finally, it has been a.s.serted in our own time that there was an immense opening at the poles, from which came the Northern Lights, and through which one could reach the inside of the earth; since in the hollow sphere two planets, Pluto and Proserpine, were said to move, and the air was luminous in consequence of the strong pressure it felt."
"That has been maintained?" asked Altamont.
"Yes, it has been written about seriously. Captain Symmes, a countryman of ours, proposed to Sir Humphry Davy, Humboldt, and Arago, to undertake the voyage! But they declined."
"And they did well."
"I think so. Whatever it may be, you see, my friends, that the imagination has busied itself about the Pole, and that sooner or later we must come to the reality."
"At any rate, we shall see for ourselves," said Johnson, who clung to his idea.
"Then, to-morrow we"ll start," said the doctor, smiling at seeing the old sailor but half convinced; "and if there is any opening to the centre of the earth, we shall go there together."
CHAPTER XXV.
MOUNT HATTERAS.
After this solid conversation every one made himself as comfortable as possible in the cavern, and soon fell asleep. Every one, that is, except Hatteras. Why did not this strange man sleep?
Was not the object of his life attained? Had he not accomplished the bold projects which lay so near his heart? Why did not calmness succeed the agitation in his ardent mind? Would not one suppose that, when he had accomplished this end, Hatteras would fall into a sort of dejection, and that his over-stretched nerves would seek repose? After succeeding, it would seem natural that he should be seized with the feeling of sadness, which always follows satisfied desires.
But no. He was only more excited. It was not, however, the thought of returning which agitated him so. Did he wish to go farther? Was there no limit to his ambition, and did he find the world too small, because he had been around it? However this may have been, he could not sleep.
And yet this first night spent at the pole of the world was pleasant and quiet. The island was absolutely uninhabited. There was not a bird in its fire-impregnated atmosphere, not an animal on the soil of cinders, not a fish in its boiling waters. Only afar off the dull murmur of the mountain, from the summit of which arose puffs of hot smoke.
When Bell, Johnson, Altamont, and the doctor awoke, Hatteras was not to be seen near them. Being anxious, they left the cave, and saw the captain standing on a rock. His eyes were fixed on the top of the volcano. He held his instruments in his hands, having evidently been calculating the exact height of the mountain. The doctor went up to him and spoke to him several times before he could rouse him from his revery. At last the captain seemed to understand him.
[Ill.u.s.tration: "They saw the captain standing on a rock."]
"Forward!" said the doctor, who was examining him attentively,--"forward! let us explore our island; we are all ready for our last excursion."