s was the sight, the sailors were terribly apprehensive of
nameless disasters in such monstrous surroundings. It was impossible
for them to understand how the ocean roof could remain suspended
above us like the vault of heaven. The idea of being able to sail down
a tubular ocean, the antechamber of some infernal world, was
incomprehensible. We were traversing sea-built corridors, whose
oscillating floors and roof remained providentially apart to permit us
to explore the mystery beyond.

Mid-day on the 13th of May brought no sight of the sun, but only a
deepening twilight, the dim reflection of the bright sky we had left
behind. The further we sailed into the gulf the less its diameter
grew. When we had penetrated the vast aperture some two hundred and
fifty miles, we found the aerial diameter was reduced to about fifty
miles, thus forming a conical abyss. We were clearly sailing down a
gigantic vortex or gulf of water, and we began to feel a diminishing
gravity the further we approached the central abyss.

The cavernous sea was subject to enormous undulations, or tidal waves,
either the result of storms in the interior of the earth or mighty
adjustments of gravity between the interior and exterior oceans. As we
were lifted up upon the crest of an immense tidal wave several of the
sailors, as well as the lookout, declared they had seen a flash of
light, in the direction of the centre of the earth!

We were all terribly excited at the news, and as the ship was lifted
on the crest of the next wave, we saw clearly an orb of flame that
lighted up the circling undulations of water with the flush of dawn!
We were now between two spectral lights--the faint twilight of the
outer sun and the intermittent dawn of some strange source of light in
the interior of the earth.

The sailors crowded to the top of both masts and stood upon
cross-trees and rigging, wildly anxious to discover the meaning of the
strange light and whatever the view from the next crest of waters
would reveal.

"What do you think is the source of this strange illumination," I
inquired of the captain, "unless it is the radiance of fires in the
centre of the earth?"

"It comes from some definite element of fire," said the professor,
"the nature of which we will soon discover. It certainly does not
belong to the sun, nor can I attribute it to an aurora dependent on
solar agency."

"Possibly," said Professor Rackiron, "we are on the threshold of if
not the