and dangerous too--how'd you ever get up the trail--we
heard it was destroyed."

"There is still a narrow path," said Mr. Jenks. "We came up that--the
lightning and landslide haven't left much of it, though."

Mr. Parker looked quickly up from the rocks at which he was tapping with
his small hammer. "You have terrific lightning up here," he said. "I am
much interested in it, from a scientific standpoint. I predict that some
day the entire mountain will be destroyed by a blast from the sky."

"I hope it won't be right away," spoke one of the men. "Now I guess you
folks had better 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, for the cavern was
too well guarded to attempt to enter it by force--at least just yet.

"Yes, we'll go back," assented Mr. Jenks.

Mr. Parker was tapping away at the rocks. He looked toward the black
mouth of the big cave. On what corresponded to the roof of it, some
distance back from the entrance, he saw a slender metal rod sticking up
into the air.

"May I ask if that's a lightning rod?" he inquired innocently. "If
it is, I should like to ask about its action in a mountain that is so
impregnated with iron ore.

"You may ask until you get tired!" cried the spokesman, again showing
unreasoning anger, "but you'll get no answer from us. Now get away from
here before we do something desperate. You're on private gro