r at an enormous pressure was used to give the torpedoes a
start, although, of course, they contained the usual machinery within
themselves to drive them through the water after they left the tubes.

There followed a moment of suspense as the compressed air, with a
hissing sound, rushed into the tubes.

Mr. Barr, deadly pale but without a tremor in his voice, announced that
all was ready.

The ensign merely nodded and began to operate a worm gear which swung
the tubes at an acuter angle to the body of the submarine vessel.

"I think we are all right now," he said presently.

"Very well," spoke the inventor, his hand on a lever, "when you say the
word, I'll discharge the torpedoes."

"You might as well do it right now," was the response.

The inventor, with hands that shook, swung the lever back.

There was a hissing sound and a slight tremor as the compressed air shot
the torpedoes from the tubes. Less than a second later, simultaneously
it seemed, the submarine was rocked and swayed by a terrific convulsion.
The boys and their elders were thrown right and left with a force that
almost knocked them senseless.

It was but a few moments after the explosion of the two torpedoes that
Ensign Hargreaves uttered a shout that thrilled them all.

"We're rising!" he cried. "My plan succeeded after all!"

"I think that we ought to give thanks to Providence," said Mr. Barr
reverently. "As the ensign has said, the plan succeeded, but it was
taking one chance in a thousand. Had that cliff not been shaken so as to
release us, we might have perished miserably and left our fate a
mystery."

The boys were in the conning tower by the conclusion of Mr. Barr's
words. The barograph showed them to be rising a hundred feet a minute.
No words were exchanged between the two young Scouts, but each grasped
the other's hand in a firm grip and gazed into the other's eyes. There
was no necessity of speech. Both realized that they had passed through
the gravest peril that even they had experienced in all their
adventurous lives.

When the _Peacemaker_ reached the surface once more, the storm had
subsided. With their hearts full of deep gratitude for the miraculous
chance that had saved their lives, her occupants headed the speedy
diving craft back for the island at top speed. The _Peacemaker_ had been
through the supreme test and had not been found lacking.

"I tell you what, Barr," declared Ensign Hargreaves, as they neared the
famil