The boys returned the Beaver call but no answer came. At times they thought they heard whispers coming from the dark reaches of the cavern, but they were not quite certain.
"There may be real Beavers in here for all we know!" suggested Will.
"That's all you know about it!" chuckled George. "Beavers only operate in running water."
"Well, isn't that water out there running?" asked Will.
"No jokes now!" replied George. "I've got all I can endure now without standing for any of your alleged witticisms!"
While the boys sat in the boat, occasionally moving it from side to side, a shaft of light appeared directly above the point where the shale had been heaped up. It moved swiftly about for an instant and then dropped out of view. It was a moment before either boy spoke.
"That's some of Tommy's foolishness!" Will declared.
George repeated the Beaver call several times, but no answer came.
"That's a searchlight, anyway!" insisted Will. "And I don't believe these ginks in the mines have electric searchlights to lug around with them!"
Will unshipped an oar and struck the water with the flat of the blade several times, exerting his whole strength.