"But it is a dangerous one!"
"Never mind that. Nothing could be more serious than our present predicament."
"Very well then, we will try out my idea. It's our last chance."
"Our last chance!" The words sounded to the boys almost like a requiem. Plainly enough, whatever Ensign Hargreaves' plan might be, there were dangers attached to it, and no light dangers, either, to judge from his grave tones. Eagerly they awaited his next words.
"My plan is nothing more nor less than this," he said; "I propose to create an earthquake."
"To create an earthquake!" Mr. Barr echoed the words, staring at the ensign as if he thought he had gone suddenly insane.
"Precisely. I intend to produce by artificial means an eruption which will destroy enough of this cliff to set us free, or else blow the Peacemaker herself into atoms."
Mr. Barr buried his head in his hands. Skillful inventor and scientific expert though he was, the last words of the naval officer had sapped even his iron courage.
"Is there no other way?"
"No other way. It's a gamble for our lives."