ry with a gale of
laughter. "A trifle heavy! Oh, my!"

"You'll find out if I sit on you," Slim threatened, in a belligerent
tone.

"Come now," said Joe, "this isn't making any progress toward capturing
the spy."

"No," Jerry responded, "and that's our first duty, even if it is a
trifle heavy."

"I've warned you," Slim snapped out.

"Quit it now," ordered Joe. "Let's get down to serious business."

"All right," agreed Jerry. "Shake, Slim, just to show there's no hard
feelings."

"Won't do it," Slim muttered.

"Oh, yes, you will," counseled Joe. "Shake hands, the two of you."

Slim's good nature overcame his feigned reluctance, but as Jerry grasped
his hand he gave Jerry a jerk that nearly took him off his feet.

"Now we're square," said Slim, as Jerry rubbed his nearly dislocated
shoulder.

"Well, that pull _was_ a trifle heavy," muttered Jerry, determined to
have the last word.

"Now my plan is this," said Joe, facing the other two seriously. "The
nearer we come to the zone of the German submarines, the more this man
will try to arrange to notify them of our presence, and to do that he
will have to use the wireless somehow. It seems likely that he would
make his effort at night, because then it is easier for him to escape
detection.

"Now if we let Lieutenant Mackinson sleep during the day we could so
divide up the work as for all of us to get some sleep, and then all
could do watch at night.

"The lieutenant could be in the wireless room, and one of us in the
battery room, while the other two did duty outside. If one of us should
hide under that stairway at the upper end of the passage, and the other
in that alcove at the other end, no one could reach the wireless or
battery rooms without our seeing.

"It would be tiresome and monotonous work, all right, but it might
accomplish the result."

"I'm willing," said Jerry, "but you and I will have to do the outside
work. Slim's a trifle heavy to get into either one of those hiding
places."

"Well, I'll cover the battery room," said Slim, ignoring Jerry's
remark.

"Let's see Lieutenant Mackinson, then," suggested Joe, and they went to
find the young officer who was convalescing from his encounter with the
spy. When he had approved the plan they got the O. K. of the captain.

And so it was, four hours later, with the lieutenant in the wireless
room, and Slim in the battery room adjoining, and Joe and Jerry stowed
away in the hiding places selected,