He reached back and laid a restraining hand on Joe's arm, indicating that he was to remain at the mouth of the inner chamber and keep watch. Joe realized his intention and remained where he was. Frank then continued.
Cautiously, he groped about in the darkness, moving slowly forward. At length his hand fell upon an outstretched arm, then a shoulder which stirred slightly.
He bent forward and shook the sleeper.
"Chet!" he whispered.
The other boy moved and began to sit up. The chains jangled.
"Quiet!" whispered Frank, fearing that his chum might be alarmed at this sudden and surprising awakening and make some sound.
"Who is it?" whispered the other.
"It's me—Frank. I've come to help you get free."
From the darkness he heard a gasp of surprise, but it was quickly silenced.
"I'll waken Biff," replied Chet. Frank had merely guessed at this being Chet Morton whom he had awakened, and found that his guess had been correct.