"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!"