ge were continued we would
find ourselves swallowed up in a vast polar gulf leading to God knows
what infernal regions.

The terror inspired by the professor's words was plainly visible on
every face.

"Let us turn back!" shouted some of the sailors.

"My opinion," said the captain, "is that we have entered a polar
depression; it is impossible to think that the earth is a hollow shell
into which we may sail so easily as this."

"If I might venture a remark," said Pilot Rowe, "I think Professor
Starbottle is right. If the earth is a hollow shell having a
subterranean ocean, we can sail thereon bottom upward and masts
downward, just as easily as we sail on the surface of the ocean here."

"I believe an interior ocean an impossibility," said the captain.

"You're right, sorr," said the master-at-arms, "for what would keep
the ship sticking to the wather upside down?"

[Illustration: THE TERROR INSPIRED BY THE PROFESSOR'S WORDS WAS
PLAINLY VISIBLE ON EVERY FACE.]

"I don't say that the earth is absolutely a hollow sphere," said the
professor, "but I do say this, we are now sailing into a polar abyss,
and if the sun disappears at noon to-day it will be because we have
sailed far enough into the gulf to put the ocean over which we have
sailed between us and that luminary. If the sun disappears at noon,
depend upon it we will never reach the pole, which will forever remain
only the ideal axis of the earth."

"Do you mean to say," I inquired, "that what men have called the pole
is only the mouth of an enormous cavern, perhaps the vestibule of a
subterranean world?"

"That is precisely the theory I advance to account for this strange
ending of our voyage," said the professor.

The murmurs of excitement among the men again broke out into wild
cries of "Turn back the ship!"

I encouraged the men to calm themselves. "As long as the ship is in no
immediate danger," said I, "we can wait till noonday and see if the
professor's opinion is supported by the behavior of the sun. If so, we
will then hold a council of all hands and decide on what course to
follow. Depart to your respective posts of duty until mid-day, when we
will decide on such action as will be for the good of all."

The men, terribly frightened, dispersed, leaving Captain Wallace,
First Officer Renwick, Professors Starbottle, Goldrock, and Rackiron,
the doctor and myself together.

Dreadful as was the thought of quietly sinking into a polar gulf from
w