at the critical moment the lad at the helm of the other craft, which
bore the name _Speedaway_, appeared to lose his nerve. He sheered off
and merely grazed the _Curlew's_ side, scraping off a lot of paint.

"Hi, there! What do you mean by doing such a thing?" demanded Jack,
directly the danger of a head-on collision was seen to have been
averted.

The other lad broke into a laugh. It was echoed by the man with him,
whom he had addressed as "pop."

"Just thought I'd see how much you fellows knew about handling a boat,"
he sneered. "It's just as I thought, you're a bunch of scare-cats. You
needn't have been afraid that I couldn't keep the _Speedaway_ out of
danger."

"You risked the lives of us all by running so close," cried Billy
indignantly.

"Never attempt such a thing again," said Jack angrily, "or----"

"Or what, my nervous young friend?" taunted the elderly man.

"Yes," said the lad, with an unpleasant grin, "what will you do?"

"I shall feel sorely tempted to come on board your boat and give you the
same sort of a thrashing I gave you the other day when I found you
tormenting that poor dog," said Jack, referring to the incident Billy
Raynor had already hinted at when he first recognized the occupants of
the _Speedaway_.

"You'll never set foot on my boat," cried Donald Judson, with what he
meant to be dangerous emphasis; but his face had suddenly become very
pale. "You think you got the best of me the other day, but I'll fix you
yet."

The two craft were out of earshot almost by this time, and none of the
three lads on the _Curlew_ thought it worth while to answer Donald
Judson. The millionaire and his son occupied an island not far from the
Pine Island Hotel. A few days before the incident we have just recorded,
Jack, who hated cruelty in any form, had found Donald Judson, who often
visited the hotel to display his extensive assortment of clothes,
amusing himself by torturing a dog. When Jack told him to stop it the
millionaire's son started to fight, and Jack, finding a quarrel forced
upon him, ended it in the quickest way--by knocking the boy flat.

Donald slunk off, swearing to be revenged. But Jack had only laughed at
him and advised him to forget the incident except as a lesson in
kindness to animals. It appeared, however, that, far from forgetting his
humiliation, Donald Judson was determined to avenge it even at the risk
of placing his own life in danger.

"I wonder if he followed us up to