With his arms still wrapped about the German commander, Jack struggled to the rail and leaped into the sea. Down and down he went, never for a moment relaxing his hold on the German. Then they came to the surface.
With a sudden jerk the German freed himself and aimed a heavy blow at Jack. This Jack dodged and sought to regain his hold on his foe. But the German wriggled away and struck out for the submarine.
In the meantime, Captain Griswold of the Ventura had been watching the struggle as his vessel sped away from the scene. There was a strange light in his eyes and he muttered to himself. At last he muttered an imprecation.
"He's a brave boy," he said. "I can't run away and leave him like that."
He brought the head of the vessel around in spite of the protests of some of the passengers, and headed back for the submarine.
"Man the forward gun there!" he cried.
For the Ventura, like other allied ships plying in the seas in those days, carried small guns for defensive purposes. The gun crew sprang to obey this order and the gun was trained on the submarine.
"Fire!" shouted Captain Griswold.
"Crash!"
The gun spoke and a geyser of water was kicked up just beyond the submarine.