"Very good!" declared Captain Jack. "So be it. And your men here, I take it, are of the same mind?"

"We are, sir," said Timothy and Allen in a single voice.

They seemed to have lost all desire to become pirates in reality.

"You may consider yourselves at liberty, then," said Captain Jack, with a wave of his hand. "By the way," this to Frank, "do you know anything of the mechanism of a submarine?"

"A trifle," said Frank quietly. "I neglected to tell you that I hold a lieutenant's commission in the British navy."

"What!" cried Captain Jack, who could scarcely believe his ears.

"Exactly," said Frank, "and as such I have seen considerable active service beneath the sea as well as upon its surface."

"So much the better," declared Captain Jack. "You will be all the more valuable. I need not fear to trust my ship in your hands."

At this moment there came sounds of confusion from above.

"Something wrong," said Captain Jack, and dashed away.