Jack sat down. Frank did likewise.

"That settles that," said Jack, briefly. "Now we had better get away from here. We haven't any too much time."

Frank, without a word, took his place at the wheel.

"Feel fit?" asked Jack.

Frank nodded, though he felt terribly faint.

"Sure you can make it?" Jack continued.

"Yes," replied Frank.

"Well, I just wanted to know," said Jack, "because here comes a German torpedo boat."

Frank was startled. He turned in his seat, and there, not a mile and a half away, was a ship of war. She was flying the German flag and was making directly for the spot where the British hydroplane rested.

"By George! Won't we ever get out of this?" the lad muttered.