“Give it up,” answered Frank. “They have disappeared, but that is as much as I know.”

“Perhaps they are laying for us.”

But, although they waited a long time, not a sound could they hear save those sounds made by themselves.

“I am going ahead,” declared Merriwell.

“We may run into them.”

“Got to chance it, old man. That might be better than to have them run away from us. Come on.”

“I’m with you.”

Keeping close together, they crept forward slowly, not knowing but they might be attacked at any moment.

Of a sudden, Frank gave a gasp and cry. Harry tried to grasp his companion, and then he found himself slipping, sliding, falling.

Down they went, getting hold of each other, but being unable to stop their descent. It was impossible to see anything there in that frightful darkness, and that made their peril seem awful indeed.