noon, when Wesley Dana returned to the yard, Pete was painting the new plank that had been put in.
“What happened?” his father asked Pete.
Pete explained. When he had finished, Mr. Dana paused for a moment.
“You can’t be sure Fannin did it,” he said. “And even if he did, how do you know he did it on purpose?”
Pete felt angry. He wanted to tell his father that Fannin was going to bring trouble to Hidden Harbor. But he knew that his father would say the same thing Nick and Professor Nevins had said.
When the paint on the repairs was dry enough, Pete once more towed the boat across the harbor.
“That was a quick job,” the Professor called out as Pete came drifting in to the beach.
“Nick is pretty good,” Pete agreed.
“And what is your special job?” Nevins asked.
“I am the gas float expert,” Pete said, grinning.
The Professor laughed. “It’s a little late for me to check all my nesting boxes this afternoon. How about your first skin diving lesson?”
“Great!” Pete agreed.
They brought the new gear down to the rowboat. Pete carried the small motor from the tent and fastened it to the stern. He started the motor and turned to the Professor.
“Where to?” he asked.
“Go down past your camp toward Lighthouse Point. We need clear water and a sandy bottom.”
Pete nodded and steered the boat to the west, toward Lighthouse Point.
“This looks pretty good,” the Professor said. “How deep is it?”
Pete stopped the motor, picked up an oar from the bottom of the boat and pushed it down into the water.
“About up to my chest.”
“Fine. Let’s anchor,” the Professor said.
Pete dropped the anchor and, when it caught, stripped down to a pair of swimming trunks. The Professor did the same and they dived into the water.
“All right, Pete,” he said. “Let’s start with the masks.”
Professor Nevins showed Pete how to wet the inside of the glass face piece in the mask. “If you don’t wet it,” he said, “it may steam up when you stay under for a while.” Then he showed Pete how to get a tight fit around the edges, so that no water would get in. After that, Pete swam under water. He was surprised at how clearly he could see.
Next, Pete tried on the rubber swim fins that fitted over his feet.
“They look funny,” he told Professor Nevins, “but they sure help. With them, I could keep up with a fish.”
“Don’t bet on it,” the Professor said, laughing. “But they do add a lot of speed under water.”
Next they put on the belts that were weighted with lead. Hanging on each belt was a bag holding a knife with a cork handle.
“You won’t always need the belt,” the Professor said. “Most of the time the weight of the oxygen tank will keep you under water when you want to stay down. But sometimes you need one, and I thought you should get the feel of it under water.”
With the belt on, Pete found he would settle to the bottom when he went under.
“Now let’s get started on the best part of skin diving—using the oxygen tank.” Professor Nevins reached into the boat and lifted out a tank about two and a half feet long, painted bright yellow. From the pointed end, two rubber tubes came out of the tank and ran to a rubber mouth piece. There was also a round knob set in the top of the tank. Pointing to it, Nevins said, “This controls the flow of air into the mouth piece. You can reach it over your shoulder when you are wearing the tank. That way, you can get more air, or less air, whichever you need.”
He held the tank while Pete slipped his arms through the two canvas straps so that the tank hung on his back. Then the Professor looped the two rubber air tubes over Pete’s head and handed Pete the mouth piece.
“Here, slip this into your mouth. You will find that you can hold it easily with your teeth. Even if you open your jaws a little, it won’t fall out. The rubber front here covers your lips so no water can get into your mouth while you are breathing.”
Pete slipped the mouth piece into his mouth and the Professor gave the handle one turn.
“Breathe in, Pete,” he said. Then, “Are you getting enough oxygen?” Pete took several breaths and shook his his head that he was not.
The Professor gave it another turn. “How’s that? Are you getting enough now?”
Pete nodded and pointed down at the water.
“All right, go ahead. Try it,” the Professor said.
Pete went under. A moment later he came up, choking for air. The Professor burst out laughing.
“It’s not funny.” Pete said.
“Sure, it is. You wouldn’t wait until I told you how to breathe.”
Pete laughed too, this time. “I thought I knew how to breathe!”
“It is a little different with the tank. You have to pull in hard with your mouth, then blow the air out through your nose.”
“Got it. Let me try it again.”
Pete dived and this time he did it right.
For the next half hour Pete practiced. He went out into the harbor for a hundred yards under water, then came to the surface. The Professor made him practice going in a straight line.
“You have to swim with an even stroke, Pete. When you stay under longer, you want to know exactly where your boat is when you come up. If I am in town tomorrow,” Professor Nevins went on, “I will pick up a couple of wrist compasses. Then we can practice doing some map problems under the water.”
Pete thought how useful a compass could be. With it, a man could approach a boat under water without being seen. And when he learned to judge distance under water, he would be able to come up just where he wanted to.
On the way back to camp, Professor Nevins said, “This time the supper is on me.”
After they had eaten and the sun was going down, Pete said, “I know everybody thinks I am off base, the way I feel about Fannin, but there is something fishy about that boat business of his. First of all, why didn’t he rent space down near the main part of town where all the people are?”
“All right, Pete. That’s one point.”
“Next, why is he buzzing around the water in the middle of the night?”
“That is point two, provided it was Fannin.”
“Third,
