"Americans!" was the cry that carried across the water. "Man the forward gun there!"
"Fire, men!" cried Jack in a loud voice. "Sweep the deck with your rifles. Don't let 'em bring that gun to bear."
There was a crash of rifles as Jack's command was obeyed. Nevertheless the Germans succeeded in training their rapid-firer, and it crashed out a moment later. A veritable hail of bullets flew over Jack's men.
At a quick command from the lads, the boats drew farther apart, thus making the task of the enemy more difficult. Then they closed in on the submarine from both sides.
Harsh German cries and imprecations were wafted to the ears of the British as the boats drew closer.
"Submerge!" shouted a voice.
"Quick, or we shall be too late," Jack roared.
The men at the oars exerted themselves to further efforts. Then Jack caught another cry from the submarine.
"We can't submerge. The tanks are still broken."
"Good!" said Jack to himself. "Now I see what the trouble is. Faster," he cried to his men.