Greatly puzzled, the lads searched the interior again and again. Not a
place large enough to accommodate even a dog was omitted. The towers
were mere shells, with here and there a huge beam of wood, all that was
left of the different floors.

A door opening upon the lake was found, but it had been impassable for
years. Masses of _débris_, encumbering the castle, were moved about, but
nothing was discovered until finally the giant, Sumo, while delving into
the darkest corner of the most remote apartment, suddenly stepped into a
hole, and narrowly saved himself by grasping at the edge.

His cries brought the whole party helter-skelter into the room. A torch
of resinous pine was lighted, and the mystery revealed. The hole was the
jagged entrance to a tunnel, the bottom of which was dimly visible in
the rays cast by the flickering light.

“It is a secret exit from the castle,” cried Nattie. “Quick! bring other
torches; we must follow at once.”

“I thought we would find something of the kind,” remarked Mori, no less
excited. “All these old _shiros_ have such outlets. It is fortunate we
have found this so easily. The other party cannot be very far in

There was much running about, but finally a start was made with an ample
supply of torches. Sumo was the only native that could be induced to
accompany the lads, the others hanging back in superstitious terror.

Word was left with one of the _’rikisha_ men to hold the police at the
castle until word arrived, then Nattie and Mori eagerly descended into
the cavity, Sumo bringing up the rear with the sticks of pine and his
ancient sword.

A few crumbling steps led to the bottom, which was about twelve or
thirteen feet from the floor. A little heap of dust at the lower level
bore the imprints of several feet. It was proof enough that the
fugitives had entered the tunnel.

A couple of yards from the entrance the excavation made a sharp descent.
The floor was thick with slime, and moisture dripped from overhead. The
tunnel became smaller and smaller and traces of masonry were found.

“We are passing under the moat,” said Mori, elevating his torch. “Ugh!
what a dreadful place this is.”

Nattie made no reply. He walked ahead steadily, and ever kept his eyes
in advance, as if eager to catch sight of the fugitives. Huge rats
peered at the party from sheltered nooks, or darted across their path,
as if careless of molestation. The silence was intense; the solitude

Presently the air became foul. It was thick and heavy with an odor like
that of a tomb. On turning a corner they suddenly came upon a row of
human skeletons stretched out in an orderly manner upon the floor. It
was a ghastly spectacle, and brought a terrified cry from Sumo. He
stopped and appeared unwilling to cross the bones.

“Come on, or remain alone,” said Nattie, grimly.

The giant porter promptly followed them, but his huge frame shook with
superstitious fear. At the end of five minutes, a brief halt was made.
The tunnel was filled with a dark, moldy air, difficult to breathe.
Gasping and coughing, Mori turned an inquiring eye to his friend.

“We must not turn back,” replied the lad. “They passed through here, and
we can also. Come; we are losing time. See, the torches are burning out.
If we do not hasten we will be left in darkness.”

The very possibility of such a dread occurrence sent the trio on almost
at a run. To be left in darkness in the tunnel, with its ghastly
tenants, was terrifying to contemplate. Sumo magnified the horrors a
hundredfold through his ignorance, and his plight was pitiful to see.

On, on; the torches flickering; grotesque shadows surrounding them; the
atmosphere becoming more dank and difficult to breathe with each passing
moment. Huge rodents pattering before, their sharp, piercing eyes
gleaming like the optics of fleeing demons; a dripping of water here and
puddles of foul scum there.

Only one thing strengthened the little party as they sped along, and
that was the knowledge that other humans had passed through the same
horrors but a few brief moments before.

“How much farther?” gasped Mori, for the tenth time.

“How much farther?” echoed Sumo, with a groan.

“Heart up,” replied Nattie, redoubling his speed. “We must be almost
there. Don’t give up. Remember Ralph and the others took the same
journey. Are they more brave than we?”

“You are right, my boy. We must persist; the end cannot be far away.”

They had already traveled a distance at least equal to two city blocks.
The tunnel had made various turns, but as yet they had not encountered
any side excavations. This was fortunate, as it permitted them to
continue ahead without any doubt as to the proper passage.

Presently, to the unspeakable delight of all three, the air became less

“We are almost there,” cried Nattie, cheerily. “Courage, courage!”

It was time. The torches, mere pine slivers, had burned away until only
a few inches remained. They had started with an ample supply, but while
passing the ghastly array of skeletons, Sumo had dropped the reserve
bundle in his terror.

Suddenly the one carried by Mori gave out; then Nattie’s gave a feeble
splutter and expired. Presently, however, the floor in the tunnel began
to brighten, and finally, on turning a corner, a feeble speck of light
became perceptible in the distance.

“The end, thank God!” shouted Mori.

The echoes of his voice had hardly died away when a most dreadful thing
happened. Without the slightest warning to herald its approach there
came a terrific rending shock. It seemed as if the very bowels of the
earth had collapsed in one great crash.

Nattie and Mori and Sumo were thrown to the ground with violent force,
and there they lay mercifully deprived of consciousness, while around
them the walls and roof and floor of the tunnel heaved and pitched in
the throes of an earthquake.

The disturbance only lasted a moment, but it was some time before the
little party recovered. Nattie was the first to stagger to his feet.
The torch had gone out, leaving an impenetrable darkness. The welcoming
light–the light proclaiming the exit from the tunnel–had disappeared.

The lad was bewildered, almost daft, and small wonder. He lurched about
until at last he stumbled and fell across Mori. The shock brought the
young Japanese to his senses. Then Sumo scrambled to his feet.

Panic-stricken, they started to run. Slipping, staggering, sorely
bruising themselves against the sides of the passage, they fled in
overwhelming terror. A yard, ten yards, a hundred yards, and then they
brought up with a crash against an impenetrable barrier of rock and

The exit was closed!