nd
brought forth two celluloid caps; one blue, and one red.

"It's been so long since we've used these Boy Scout signals," he add,
"that I've almost forgotten which color we use for the dash and which
for the dot when we signal in the Morse code."

"The red is the dash," explained. George. "What are you going to do?"

"I'm going to hoist a signal of distress," laughed Sandy.

"Expect it to show through the rocks?"

"I guess it'll show out of any opening we can look out of!" exclaimed
Sandy. "I'm going to put on the red cap and set the light where it'll
shine through the two outer caverns. If any of the boys come within
sight of it, they'll understand the scrape we're in."

"Great head!" exclaimed George. "The boys will be coming back from
Katalla before long, and Will and Ed will naturally be searching for us,
so we're pretty sure to have the signal seen and answered before
morning!"

"That's our only hope!" replied Sandy. "Unless our Boy Scout signal
brings one party or the other, we're likely to starve to death in this
rotten old cavern. Let's see how it works," the boy went on, screwing
the red celluloid cap firmly over the eye of the electric.

After seeing that everything was in order, he switched to the blue cap.
In both cases the light worked perfectly.

"There you are!" he said with a chuckle. "If one of the boys sees the
red light, he'll read it for a Morse dash and if he sees the blue light,
he'll read it for a Morse dot!"

CHAPTER XVIII

THE ROCKS TUMBLE DOWN

After the departure of George and Sandy from the cabin, Will and Ed
decided that the best thing they could do would be to go to bed. They
had been without sleep for many hours, and were thoroughly exhausted.

"I am anxious to know what success George and Sandy have in chasing
Cameron," Will said, as he disrobed in the dark and tumbled into his
bunk, "but I don't see how we can help matters any by sitting up."

No answer came from the bunk occupied by Ed save a prolonged snore, and
Will knew that his companion was already in the land of dreams.

When Will awoke it was broad daylight and the sun was high in the
heavens. Looking at his watch, he was surprised to see that it was after
twelve o'clock. In a moment, he heard Ed stirring in his bunk, and then
the boy sat up, rubbing a pair of sleepy eyes.

"That was a corker!" Will exclaimed.

"Have any of the boys returned?" asked Ed.

"Oh, they're back before this, of course," Wi