. Because of the shallower water
they would have a little more time, perhaps another five minutes before
constricted breathing told them only a few minutes of air remained.

Scotty found a puffer and waved at him, but the fish paid no attention.
Scotty motioned to Rick, then reached out and scratched the creature's
stomach. It began to gulp water until it resembled a balloon. They left
it to return to normal in its own time. On the surface, the puffer would
have gulped air in the same way. They had caught them on lines many
times.

They were past the _Water Witch_ now, Rick estimated. He hooted at
Scotty, then led the way up to a depth of about forty feet. There he
started back along the cliff.

Suddenly he wished he had brought a game bag attached to his belt. The
reef here was alive with shellfish. He identified cowries, whelks, and
some excellent specimens of Triton's horn. They would have to come back
again, to collect some to take home. The biggest problem was getting the
animals out of their shells, unless there were some anthills on the
island. Ants would do the job neatly in a few days.

Scotty hooted, and pointed. Directly ahead was a small shelf. Rick moved
to Scotty's side and saw the dark opening of a cave. Next to the opening
was a small octopus. As they approached he changed color, trying to
imitate the multicolored coral against which he rested.

Rick reached out a hand and the animal retreated, sliding into the mouth
of the cave. Apparently this was his home, because the ledge was
littered with shells from a number of meals.

Now Rick wished for his camera, then smiled inwardly. To satisfy all his
unexpected wishes he would need a sort of underwater trailer to tow his
gear.

Scotty moved close to the octopus and it retreated still further. Both
boys knew the creatures were harmless to divers, and some divers even
handled them. But there were reports of divers being bitten while
playing with octopuses, and they had learned long ago that unnecessary
risks were foolish.

Rick suddenly rocked back as his ears were smitten by sound. A wail
echoed in his head, so intense that it almost hurt. Scotty started, too,
and reached for the ledge in his astonishment.

The octopus peered out of the cave, and the wail came again, buzzing
uncomfortably in their heads. And in that moment, Rick's air gave out.
He pulled the reserve lever and planed to the surface, Scotty close on
his heels.

On the _Water Witch