e bell cord,
jangling out a "go ahead" signal to Harry. As the latter touched the
levers a startling crash at the stern of the craft was heard.

The motors spun the shaft around futilely without making headway.

With blanched faces the lads glanced about the craft. Harry's hand
instinctively sought the levers again to turn off the current.

"What's the matter?" called Jimmie from his position.

"I don't know!" declared Harry. "It sounded as if that fellow had tied a
can to us and we'd set it going! What did he do?"

"Let's pump the ballast out and rise straight to the surface," suggested
Ned. "I noticed that he did that. Maybe there's a reason!"

Harry lost no time in acting on this suggestion. The electric pumps were
not long in emptying the ballast tanks. With this weight removed, the
boat quickly shot upward to the surface.

As the conning tower portholes rose above the surface, the boys noticed
that the afternoon was far spent. Darkness already was gathering.

Ned was working frantically at the clamps securing the hatch cover. With
a cry of delight he swung the cover out of position, admitting a cool
breeze. The wind had died down, leaving the surface of the ocean
comparatively smooth. Sufficient breeze was moving, however, to serve the
purpose of airing out the interior of the craft without putting the great
fans into commission. All the boys came to the tiny deck.

Lying but a few fathoms from their port side they discerned the other
submarine. Clearly distinguishable on the sides were the great letters
"U-13" painted in almost exact duplicate of those on their own boat.

"What do you know about that?" was Jimmie's surprised exclamation. "If
that fellow isn't a dead ringer for this ship, I'm a Dutchman!"

"He surely does look a whole lot like us!" agreed Ned.

"I say, Frank," put in Harry eagerly, "is that the fellow that sank the
ship you were on? Can you identify it now?"

Frank shook his head hesitatingly before he answered slowly: "Boys, I
hate to say it, but it looks as like the other as two peas. I would not
like to make an affidavit, but I'm willing to say that it bears a most
remarkable resemblance to that other one, if it is 'other'!"

"Then, I guess we're done for!" despaired Jack. "If that's a German
craft, we may as well hoist the white flag now and surrender!"

"Think they'll take us back to Germany?" asked Ned quizzically.

"I'm sure of it!" declared the boy. "And we won't stand much