be leaving while there's a path left to go down by."
"Might I ask," broke in Mr. Parker, as calmly as though he was lecturing to a class of students, "might I ask if you have noticed any peculiar effect of the lightning up here on the summit of the mountain? Does it fuse and melt rocks, so to speak?"
"What's that?" cried the spokesman, with a sudden flash of anger. The two men looked at each other.
"I wanted to know, merely for scientific reasons, whether the lightning up here ever melted rocks?" repeated Mr. Jenks.
"Well, whether it's for scientific reasons or for any other, I'm not going to answer you!" snapped the man. "It's none of your affair what the lightning does up here. Now you'd all better 'vamoose'—clear out!"
"All right—we'll go," said Tom, quickly, at the same time motioning to Mr. Jenks to agree with him. The eyes of the young inventor were roving about. He saw what looked like a second trail, leading down the mountain, from the far side of the cave. He was convinced now that there was another way to get to it. Possibly they might find it. At any rate nothing more could be done now. They must go back,
