Gloom possessed the hearts of Tom and his friends. Not only had their expedition been almost a failure so far, but the young inventor was worried lest the gang might discover and wreck his airship. This would prove a serious loss. Lying there in the semi-darkness the lad imagined all sorts of unpleasant happenings.
At times he dozed off, as did the others. They had become somewhat used to the pain caused by the bonds, for their nerves were numb from the strain and pressure.
Once, as he was lightly sleeping, Tom was awakened by hearing loud voices in the main cave. He looked out, rolling over slightly to get a better view. He saw the man who, once before had run in to give news of an approaching electrical storm.
“Are you fellows all ready?” asked this same man again.
“Yes. Is there another storm coming?”
“Yes, and it's going to be a corker!” was the reply. “It's one of the worst I've ever seen. It's sweeping right up the valley. It'll be here in an hour.”
“That's good. We need a big flash to make all the material we have prepared into diamonds. It's the biggest batch we ever tried. I hope it succeeds, for we're going to leave—” The rest was in so low a tone that Tom could not catch it.
The storm messenger departed. Folwell and Munson busied themselves about the machinery. Tom dozed off again, dimly wondering what had become of Bill Renshaw, and whether the former ghost knew of their plight. The others were asleep, as the young inventor saw by the dim light of a lantern in the cave. Then, he too, shut his eyes.
Tom was suddenly awakened by feeling some one's hands moving about his clothing. At first he thought it was one of the diamond-making gang, who had sneaked in to rob him. “Here! What are you up to?” exclaimed Tom.
“Quiet!” cautioned a voice. “Are you all here?”