the main shrouds of the wrecked ship. When the
man reached a position level with their craft he began making signs and
motions. In his hand he flourished a knife.

"Looks rather bad for us!" commented Jack.

"Don't you get him?" asked Jimmie impatiently. "He understands our
predicament and intends to help us! He motioned out that he is going to
climb the rigging until he can find the rope. Then he'll slide down it
until he lands on our stern. If we'll agree not to start the engines
while he's there, he'll cut the rope. But we must be ready at the ballast
tanks to let the vessel settle slowly to the deck of the ship, so he can
get off and clear the line from the propeller!"

"I don't believe it!" stated Jack. "I think he meant to cut the line as
soon as he gets to it and let us settle down slowly. What would be the
sense of his riding around the ocean seated on the stern of a disabled
submarine? He's got too much sense for that!"

"Maybe you're right!" admitted Jimmie. "Let's float the boat on an even
keel and see. I'm going to dress again!"

Even as the lad hastened to put on his clothes the boys felt a sudden dip
made by the submarine. Gradually they descended.

"Hurrah, he did it!" exultantly cried Ned. "Now, where has he gone? I do
hope he'll free the propeller wheel at once!"

"We could rise to the surface even if the propeller is stuck!" declared
Harry. "I can pump the ballast all out of the tanks!"

"But if we do that we'll have to dive overboard to clear the wheel!"
protested Frank. "I know that water is good and cold!"

"Wait a minute, boys, and see what the fellow does," cautioned Ned.
"Maybe he wants to help us, so it wouldn't be nice to run away!"

"Here he is, now!" cried Jack from his position near a porthole. "He's
looking through the glass, and making motions again!"

"I know what he wants!" declared Harry. "He's making motions for us to
unscrew a pipe! He wants us to let in a lot of the ocean!"

"Wait a minute, Harry!" put in Ned. "He's walking toward his own boat.
Let's see what he's going to do!"

In a short time their rescuer had reached the side of his own vessel. He
stepped into an open door in the side and disappeared.

"An air lock!" cried Ned. "Did you see that, boys?"

"Just like the little old Sea Lion we used in the China Sea!"

"Here he comes again with a line!" announced Harry. "Now what?"

The boys heard a hammering and thumping near one of the sea cocks.

CHAPTER