n sight was wonderful. Over and
over again it would be repeated, as the huge fish circled the vessel;
then it would vanish as suddenly and mysteriously as it had come.

"But s'pose we wounded 'em?" asked Bob hesitatingly the first morning.

"Nonsense!" laughed the captain, taking a quick shot at one of the
flashing bodies a hundred yards away. "In the first place, you're not
likely to score a hit, Bob. In the next place, these are little
twenty-two caliber bullets; unless it happened to penetrate a vital
part, one of these little pellets won't bother a ten or fifteen-foot
porpoise. It might sting him a little, if it penetrated his hide, but
that's all. It'll give you the best kind of shooting practice, too."

Reassured by this speech, the two boys pitched in. There was no lack of
ammunition aboard the _Seamew_, and there seemed to be no lack of
porpoises anxious to serve as moving targets. And, indeed, Mart soon
found that he need spend no worry over leaving wounded fish to flounder
out their lives.

So rapidly did he have to shoot, so quickly did he have to meet the
unexpected risings of the porpoises, that it was several days before he
could begin to come anywhere near the mark. Bob did better, having had
more practice in shooting, and the captain proved himself a past master.
But at no time did any thought of cruelty occur to either of the boys
again, since it proved to be exactly as Captain Hollinger had said, and
they saw no sign of dead or wounded fish in their wake.

"I wouldn't mind shooting a shark," declared Mart one morning to his
chum. "Do you s'pose one of these rifles would kill one?"

"What--twenty-twos? Not much!" and Bob laughed scornfully. "They can
stand an awful lot o' bullets, Mart. I tell you--next time you sight a
shark after us, I'll get a couple o' dad's thirty-thirty rifles and
we'll have some real shooting."

Two days after this, indeed, a shark was attracted under their counter,
and each boy got a shot at him. What effect the bullets had, they never
knew, for the shark turned and disappeared rapidly. Mart had missed, not
allowing for refraction, while Bob's shot had gone true, but they had
learned their lesson. The next time a shark showed up, they hooked him
first, then began target-practice with the heavy rifles.

The shark, while having comparative freedom of action, was forced to
follow the ship, and the two boys pumped bullet after bullet, while the
crew cheered or mocked their e