“Oh, these English can’t shoot,” Jack heard the commander say at last.  “However, I guess we have delayed long enough.  Inside with you, gentlemen.”

Two of the Germans descended through the conning tower.  This left four on the deck of the submarine besides the commander.  These, too, moved toward the conning tower.

“Guess it’s time to get busy,” Jack muttered.

With a single movement he leaped to the rail of the Ventura, and with a second hurled himself to the deck of the submarine, landing in the midst of the startled Germans.

At the same moment, Captain Griswold, on the Ventura, signalled his engine room for full speed ahead in accordance with Jack’s instructions.

The reason for this was obvious.  First, it would take the steamer out of the way of the torpedoes already trained on her, which would not be launched without a command from one of the enemy officers, and, second, it would draw the Ventura away so as to present the submarine as a clear target for the guns of the approaching Essex.

Jack, on the deck of the submarine, recovered himself before the German officers could get over their surprise.  He sprang to his feet and waded into them, striking out right and left.

Two men went staggering across the narrow deck and toppled into the sea.  The others reached for their revolvers.  Before they could fire, however, Jack sprang forward quickly and floored one of the enemy with a smashing blow.  This left the commander and one other officer on deck.

The commander fired at Jack, but in his haste the bullet went wild.  Jack hurled himself forward, and the men gave ground.  One, retreating, lost his balance and went staggering across the deck and fell overboard.

Only the commander of the submarine now faced Jack, and he covered the lad with a revolver.

“Hands up!” he said.

For answer Jack smiled slightly, and took a quick step forward.

“Crack!” the German’s revolver spoke sharply, and Jack felt a hot pain in 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.