ne. "I
feel kind of foolish. After all, what could happen? That old cowman
pal of yours looks pretty capable."

"He is, too," said Frank. "Just the same, I feel we ought to be
cautious. If Tom's all right when we reach the cave, well and good.
But if he isn't------"

"You're right, kid," said Stone. "I'm no more of a coward than the
next fellow. But if Morales and Von Arnheim by any chance gained the
upper hand and got their clutches on me, I'd hear the birdies sing."

Frank had been thinking rapidly.

"Look here," he said, "isn't there some way we can sneak up there to
find out if matters are all right or not? Suppose Tom has been
overcome. We wouldn't stand much chance approaching the cave by the
regular entrance." He paused and again stared upward. "We've been gone
a considerable time," he said nervously. "You'd think if he were all
right, Tom would have called to find out what is delaying us."

"Tell you what," said Stone, "I've got a little private path to the
top of the cave where the antenna is located. It isn't much more than
a goat track. But we'll have to be goats. Never been up it in the
dark, but I think I can make it. Are you game to follow me?"

"Certainly," said Frank, "if it will be of any advantage for us to do
so."

"Well, there's a fissure through the rock down into the cave. That's
where the Germans that put in the radio plant made their hook-up. We
can listen there, and maybe hear something to guide us."

"Oh, I remember that," said Frank, and added excitedly: "Maybe I could
crawl down into the cave."

"You might be able to, at that," said Stone. "You're pretty slight.
But it would be a ticklish proposition without any rope from above.
Well, if you're on, let's go."

Turning he struck off across the valley, approaching the hill some
distance from the path leading to the cave. Frank followed closely at
his heels. Soon they began mounting upward. The climb in the darkness
became more and more difficult, made more so by the care they
exercised to prevent dislodging stones. They feared the clatter of
these descending to the bottom would betray them.

Once Stone, who was in the lead, slipped and slid backward, clutching
frantically to stay his fall. Fortunately, Frank was well braced at
the moment and was able to stop him. After a rest to regain their
breath and calm their shaking nerves, they resumed the climb.

At length Frank's feet were on level ground and ahead he saw the
outlines of