ore 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 mass 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 Ne