He knelt at the rim of the circular opening and looked into the depths of the pit, Tommy following suit. The feeble ray of the flashlight was lost in the blackness below.
"Say, Frank," whispered Tommy, "turn off the flash. I think I saw a light down there."
And, with the snapping of the catch, there came darkness. But, miles below them, it seemed, there was a tiny pin-point of brilliance—an eery green light that was like a wavering phosphorescence of will-o'-the-wisp. For a moment it shone and was gone. Then came the dreadful vibration they had experienced in the hall of the house—the whistling scream that grew louder and louder until it seemed they must be deafened. The penetrating wail rose from the depths of the pit, and the vibration was all around them, in the damp rock floor on which they knelt, and in the very air of the cavern. Hastily Frank snapped on the light of his flash.
"Oh boy!" he whispered. "Leland is certainly up to something down there and no mistake! How're we going to get down?"
"Get down?" asked Tommy. "You don't want to go down there, do you?"
"Sure thing. We're this far now and, by George, we're going to find out all there is to learn."
"How deep do you suppose it is?"
"Pretty deep, Tommy. But we can get an idea by dropping a stone and counting the seconds until it strikes."
