She was an excellent swimmer, almost as good as
Barby. But she had never had experience with mask, fins, and snorkel,
so lessons in the use of those were required before she could graduate
to the aqualungs.

"Let's go," Rick said.

In a short time the four had changed to swimming suits and were
testing the water off Pirate's Beach. It was cold, but not unbearable.
Once they were accustomed to it, Rick picked up the instructions where
he had left off the day before. Jan was using Barby's mask, snorkel,
and fins. They would get her some of her own on the first trip to
Whiteside.

Barby had borrowed her father's equipment. The mask wasn't a perfect
fit, but she was experienced enough not to mind a little leakage. The
snorkel was all right, since no fit was involved, but the fins were
ludicrous on her small feet. She had stuffed cotton in the toes to
make them tight enough to wear, but that made the fins hard to
control.

"Follow the leader!" Rick called. "I'll lead, Jan next, Scotty next,
and Barby bring up the rear."

That was so Scotty would be instantly aware of any trouble Jan got
into. Barby could swim as well as either of the boys and needed no
watching.

Rick started by going straight out, watching the bottom through his
mask. When he got to about the fifteen-foot depth, he bent at the
waist and threw his legs upward. He slid smoothly into the water,
rolling on his back to watch Jan. She imitated his movements
perfectly, and he turned back, satisfied. She was graceful as a seal
in the water. It wouldn't take much to make a first-class diver out
of her.

Rick went to the bottom and moved along, doing underwater acrobatics
and touching a rock here and there. Then he turned over on his back
again and started upward, eyes on Jan. She followed. He led the way
back to the beach.

As the group emerged from the water and lifted their masks, Rick
looked at Scotty. His pal nodded. "She'll do. She followed you like a
shadow."

"Good. All right, Jan. Next step is clearing your mask of water. The
principle is easy. Just remember that gas is lighter than liquid. Your
breath is lighter than the water. So you hold the top of your mask and
blow it full of air, which forces the water out the bottom. Watch."

He demonstrated a few times, then Jan tried it. She caught on easily.

The instruction continued, until at the end of two hours, Rick took
all of Jan's equipment and threw it into twelve feet of water. "Now,"
he