"Well, if your gun will do that to a whale, what will it do to an
elephant?" asked Mr. Durban one morning, when they were within a
day's steaming of their port. "I'm afraid it's almost too strong,
Tom. It will leave nothing--not even the tusks to pick up."

"Oh, I can regulate the power," declared the lad. "I used full force
on the whale, just to see what it would do. It was the first tine
I'd tried it on anything alive. I can so regulate the charge that it
will kill even an elephant, and leave scarcely a mark on the beast."

"I'd like to see it done," remarked the old. hunter.

"I'll show you, if we sight any sharks," promised Tom. He was able
to keep his word for that afternoon a school of the ugly fish
followed the steamer for the sake of the food scraps thrown
overboard. Tom took his position in the stern, and gave an
exhibition of shooting with his electric gun that satisfied even Mr.
Durban, exacting as he was.

For the lad, by using his heaviest charges, destroyed the largest
sharks so that they seemed to instantly disappear in the water, and
from that he toned down the current until he could kill some of the
monsters so easily and quickly that they seemed to float motionless
on the surface, yet there was no life left in them once the electric
charge touched them.

"We'll use the light charges when we're killing elephants for their
tusks," said Tom, "and the heavy ones when we're in danger from a
rush of the beasts."