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 advance."
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 painful.
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.