“No,” replied Isaac Coffran, thoughtfully. “We’ll leave that to the working of natural laws. You may be an accessory to the crime, if it pleases you.”
* * *
He went to the center of the cavern, and lifted a wooden slab in the ground. Beneath it was a deep pit, covered by an iron grating, fastened with a padlock.
The purpose of the pit was obvious. It served as a drain for any water that might enter the cavern.
Isaac Coffran unlocked the padlock, and tugged at the iron grating. It was too heavy for him to lift. Birdie Crull assisted.
“Put them in here,” said the old man. “Cut them loose. Let them fight to get out. It won’t do them any good.”
Harry Vincent was lowered first. He was held above the pit. Vernon cut his bonds; then Crull and Jerry dropped him before he could struggle free. He fell into slimy mire at the bottom of the pit. The walls were slimy, too. He could not scale them.
Staggering to his feet, he stood to one side as Marquette came tumbling into the pit. The secret-service man’s bonds had been cut. He and Harry were trapped together.
The grating clanged shut, and the padlock snapped. They could scarcely reach the grating with their hands.
The end of a hose came through the grating. Isaac Coffran’s fiendish scheme was now apparent. He planned to fill the pit with water!