He had regained his feet and was tiptoeing toward the bell rope when a warning hiss from Yappi reached him. He turned toward the hole.
“What is it, Yappi?” he whispered.
“Come back! Light coming!”
Surely enough, at that moment a light flashed on the winding steps and began to descend. The professor made a wild dive for the hole and then stopped with a groan. It would take him several moments to worm his way back into the passage, and already it was too late for that. Sackett was coming down the stairs with the lantern, and he was now in plain sight around the last turn.
For an instant the professor remained rooted to the spot as though paralyzed. The leader of the gang was approaching the door, holding the lantern before him, his eyes squinted more than usual as he tried to see into the cell. Yappi had disappeared somewhere, and the professor felt suddenly alone and miserable.
Sackett looked in the dungeon and his eyes fell on the block which had been removed. With a snarling oath he saw the hole in the wall and turned red and angry eyes on the professor. But the old teacher had decided on his course of action.
Without fully realizing why he did it the professor stepped to the bell rope and pulled it with all his strength. The bell in the tower pealed out with a terrific clash, sending the tocsin booming out over the mountain side. Sackett saw the move and a great light swept over him.
“So!” he shouted, above the clanging of the bell. “You’re the one who is ringing that bell!”
Swinging the handle of the lantern over his arm he dived viciously into his pocket for the key to the padlock. As he did so there was the sound of running footsteps over his head and Abel’s voice reached them.
“That bell is ringing again, Sackett!” the mate cried, his voice showing his alarm.