fugal motion, and wherever we are on the interior
surface we swing round our circle of latitude in twenty-four hours,
and thus men, ship, and ocean are held up against the interior vault
like a boy being able to hold water in a vertical position at the
bottom of the pail he swings round him at the end of a cord."

"Don't you think, professor," I inquired, "we will become heavier as
we approach the region of greatest motion under the equator?"

"I don't think so," he replied, "for the ocean around the poles has
naturally gravitated to the internal as well as to the external
equator, to restore the equilibrium of gravity. The reason why a man
does not weigh less on the external equator than at the poles,
although flying around at the rate of a thousand miles an hour, is
that the deeper ocean, that is, the extra twenty-six miles that the
earth is thicker on the equator, counterbalances by its attraction
the loss of weight due to the rapid centrifugal motion, and so
preserves in all objects on the earth a uniform weight."

"The whole thing," said Flathootly, "is as clear as mud. I'm glad to
know, sorr, I haven't lost me entire constitution at all evints, an'
if I can only carry home what weight I've got lift I'll make a fortune
in a dime museum."

CHAPTER IX.

AFLOAT ON THE INTERIOR OCEAN.

As the _Polar King_ sped southward over the interior sea the wonders
of the strange world we had discovered began to dawn upon us. The
colossal vault rose more and more above us and the sun threw his mild
and vertical rays directly upon ship and sea, producing a most
delightful climate. The ocean had a temperature of 75 degrees Fahr.
and the air 85 degrees. We were absolutely sailing upside down to an
inhabitant of the outer sphere, yet we seemed to ourselves to be
sailing naturally erect on the sea with the sun above us.

Our first experience in the internal sphere was that of a sudden
storm. The sun grew dark and appeared like a disc of sombre gold. The
ocean was lashed by a furious hurricane into incredible mountains of
water. Every crest of the waves seemed a mass of yellow flame. The
internal heavens were rent open with gulfs of sulphur-colored fire,
while the thunder reverberated with terrible concussions. The ship
would spin upon the water as though every wave were a whirlpool. A
golden-yellow phosphorescence covered the ocean. The water boiled in
maddening eddies of lemon-colored seas, while from the hurricane dec