He looked up as the boys and the naval officer entered.
"The engines won't back her out?" he asked in a voice harsh and rough from anxiety.
"No. I'm sorry, Barr, but we're in a mighty bad fix. This submarine cliff must be of a sort of blue clay formation that is common off this coast. We have apparently driven into it so far that nothing short of an earthquake would dislodge us."
"An earthquake?"
"Yes; such a spasm of nature alone can set us free."
"Then we are doomed to remain here."
"Not of necessity; we have still a chance of escape."
"What do you mean?"
"That my plan offers a mere chance."
"Then let us not delay in putting it into execution."