um had succeeded in hurling Don Melville away from him, and
now the all but exhausted boatbuilder came through the forest with
lumbering steps.

All of a sudden the downed fugitive began to fight, and Jack was forced
to be strenuous.

"Here, let me take him. I'll quiet him," promised Jacob Farnum, grimly.
That gentleman was in a state of mental maze over the sight of what at
first appeared to be two Jack Bensons fighting each other; Yet the
incident gave him evidence that there was something unusual in this
night's appearances. Without any difficulty, now, he separated the
real from the false Jack, and promptly laid hands on the latter.

Don Melville's face was now a sickly white, but he felt that he had to
act on the instant.

"Here, let that fellow go," he ordered, darting up, his eyes blazing.

"Get back there! Stand away! Hands off!" roared the submarine boy,
facing young Melville and sending him back by a blow in the chest.

"Let that fellow go!" insisted Don, angrily. "If you try to hold him,
I won't be responsible for what I do!"

"I can tell you what you'll do, if you try to mix in at all where Mr.
Farnum is busy," retorted Jack, facing his foe with a savage grin.

Nevertheless, Don, espying a stick of wood lying on the ground, snatched
it up, then tried to dart around Captain Jack in order to get at Mr.
Farnum, who was having a rather one-sided struggle with the recent
fugitive.

But Jack stopped Don--stopped him all of a sudden, by rushing at him
and forcing him back up against a tree trunk. Whack! thump! It was
no time for delicacy. Young Benson struck Don two hard blows in the
face, next wrenching the stick away from him.

"The ground's good enough for you--full length!" snapped Jack;
wrathfully. Leaping at the Melville heir once more, he bore that
angered youth to the ground. Had not Don been winded by so much running
he would not have been so easy to handle.

"Now, you stay there," commanded Jack, testily. "I believe you know a
good deal about things that have happened to me to-night, and we've got
to get it all straightened out."

"I've got this one, Jack," called Mr. Farnum, gleefully.

The arrival of the real Jack Benson on the scene, in contrast with the
sham one, had opened the boatbuilder's eyes. He could not fathom, yet,
what it all meant, but he was certain that his hitherto trusted young
captain would be able to explain it all satisfactorily.

The young stranger in bl