his left arm. But the German had no time to fire again, for Jack was upon
him, pinning his revolver arm to his side.

"Now," said the lad, "I've got you!"

The two wrestled across the deck.

CHAPTER XVI

THE FIGHT ON THE U-87

In the meantime, members of the crew hearing the commotion on deck, rushed
up to see what was going on. Seeing their commander struggling with an
enemy, they hurried across the deck.

Jack saw them coming out of the tail of his eye. It was not time to
hesitate and the lad knew it.

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.

At this point the officer left in command of the submarine seemed to
realize his own danger. He sprang to the conning tower, unmindful of the
fact that his commander was struggling in the water.

"Down, men!" he cried.

But it appeared that the German sailors were made of sterner stuff than
was the officer. They refused to go below until their commander had been
brought safely aboard. In vain the officer pointed out their danger.

Jack struck out after the German commander as the latter swam for the
submarine. The lad was a powerful swimmer and he felt confident he could
overtake the man before help could reach him.

The destroyer Essex had now drawn close. Frank had been afraid to order a
shot at the subm