slowed down and the men talked among
themselves.

"They wear British uniforms," said one in a low voice.

"That's no sign they are English," said another.

"Tell 'em to give the countersign," said a third.

Another hail came from the boat.

"Pass the countersign," it said.

"I don't know any countersign," replied Jack, and would have said more,
had not a voice from the other boat interrupted him.

"I thought not; hands up now or you are dead men. Quick!"

Jack made his decision in a moment. Much as he would have liked to fight
it out, he determined upon a wiser course.

"Hands up, Frank," he said quietly. "They've got the drop on us."

He raised his hands in the air.

Not so Frank.

"They won't get me without a fight," declared the lad angrily, and,
raising his voice, he cried:

"Come and get me, if you want me."

At the same moment he raised his revolver and fired.

"Here," cried Jack angrily, "don't be a fool. Give me that gun."

He seized Frank's wrist and wrenched the revolver from his grasp.

The latter turned on his chum angrily.

"What do you mean by that?" he demanded. "Have you turned coward, that
you surrender to a couple of Germans without a fight?"

"I haven't turned crazy," replied Jack quietly. "They are too many for
us; that's all."

The other boat came alongside now and an officer stepped aboard the
boys' craft.

"Your weapons," he said in perfect English.

"Then please step aboard my boat. You shall be taken to Gravesend at
once."

"Gravesend!" echoed Jack. "You couldn't take us to a better place. But
if you are German, why should you take us there?"

"German," repeated the man. "You know we are English. You are the German
spies."

"No such thing," declared Frank, taking a hand in things. "We are
British officers and we thought you were German spies. That's why I
fired at you. We thought you were here to learn the secret of the
vanishing submarines."

"Frank!" cried Jack in warning, but it was too late.

"The vanishing submarines, eh?" repeated the stranger. "So you have
given yourselves away. Who but a German spy would be here seeking word
of the vanishing submarines?"

"But I tell you----" began Jack.

"Silence," thundered the officer. "You have betrayed yourselves, and
that is enough. I give you my word you shall be shot in the morning."

"Oh, I guess not," replied Frank with a laugh. "I guess Lord Hastings
will be able to get us out of this mess."

"Lord Has