CHAPTER XIX

Pearl Diving

“Before we go out, we’re going to have a dry run with the Scubas,” Biff’s uncle announced.

Biff, Derek, and Uncle Charlie were on the beach where the cruiser was anchored.

“Don’t know how much skin diving you’ve done, Derek—you said some—but Biff can tell you that all diving equipment must be carefully and thoroughly checked out before you go down.”

Derek paid sharp attention.

“Don your Scubas,” Charlie ordered.

The boys quickly slipped on face masks, helmets, water lungs, snorkels. Charlie helped them strap their compressed-air tanks on their backs.

Next the boys put on their weight belts. Into a rubber scabbard on each belt went a wickedly sharp knife. There were sharks in these waters. A depth gauge and watch were strapped on each boy’s left wrist.

Charlie inspected each item of diving equipment carefully. He tugged at straps, examined each piece of gear separately.

“Jettison belts!” he called out suddenly.

With a flip of his hand, Biff hit the catch on his weight belt. It dropped to the sand. Derek was a few seconds longer.

“Seconds can count, Derek, if you get into trouble. Try it again.”

Derek slipped his weight belt back on. Charlie shouted the order. Derek hit the catch, and his belt dropped.

“That’s better, Derek. Remember, that belt is what holds you down. If you have to come up fast, you’ve got to get rid of that belt fast.”

“But don’t try to come up too fast, Derek,” Biff said. “Especially if you’re down deep.”

“Biff’s right. A good rule to follow is not to rise to the surface any faster than the escaping air bubbles. Your body has to adjust to the variations in water pressure. All right, let’s go out and try it in the water now.”

They climbed in the dory. Uncle Charlie started the outboard, and they moved offshore about fifty feet.

“Sound for depth, Biff.”

Biff dropped a sounding line overboard. He pulled it up, examined the leads marking off every three feet.

“Thirty feet, Uncle Charlie.”

“Okay. Now you know how to clear your masks.”

Both boys nodded their heads.

“I want to hear you tell me.”

Biff began promptly: “If water seeps into your mask, clouding the glass and obscuring your vision, you roll over on your back—”

“Take it from there, Derek,” Charlie cut in.

“Then—then you blow air out through your nose. The air pressure building up in the mask will force the water out around the edges of the mask.”

“Good. You both know the most important safety feature of skin diving. Okay, over you go.”

The boys slipped their swim fins, or flippers, on their feet and lowered themselves overboard. They sank slowly to the bottom.

At this point, the bottom was smooth, clean white sand. Biff and Derek moved around, using their legs and feet only for propulsion. Biff came up to Derek, circled his thumb and forefinger together, indicating that everything was going smoothly. Derek replied with the “V for Victory” sign. Then they rose to the surface.

When they broke water, Charlie Keene was waiting with another order.

“Down again, and as soon as you touch bottom, jettison your belts.”

Down they went again. Charles Keene was taking no chances on the boys’ safety and ability to skin dive.

Up popped the boys, their wet heads appearing above the water first and looking like strange creatures from the deep. Biff flipped back his face mask.

“Good work, Biff. But you’ve got to go back down and retrieve the weight belts. Here’s a spare. You’d find it tough to get down thirty feet without it.”

Derek climbed aboard the dory while Biff submerged to pick up the belts. He had to make two trips. The weight of three belts would have held him down.

“We might as well start our search off this island first. Good as any.”

The dory sped out to a point Uncle Charlie estimated to be about a mile away. The anchor was tossed overboard. The sounding line showed the water depth at just over forty-five feet.

“I want you to take this spear along with you, Biff.” Uncle Charlie handed his nephew a wicked, lethal-looking weapon. Its tip was needle sharp.

“I doubt you’ll run into any bad fish here. But you might. And don’t, _do not_ use it except in case of extreme danger. If you spear an attacking fish—shark, barracuda or octopus—remember any blood will attract other sharks, and then you’ll be in real trouble.”

Biff took the spear and examined it.

“Each of you take one of these wire baskets. They’re to load the oysters in—if you find any. I’m the puller-up. I’ve a line on each basket. Now get these signals. I want both of you to give me one sharp tug every ten minutes. That will tell me you’re okay. Give two sharp tugs when your basket is filled. I’ll pull the basket up, unload it, and lower it again. Now, in case of emergency, a series of sharp tugs will alert me, and I’ll be right down. Got it? Okay. Over you go.”

The bottom was different this time. Instead of clean, white sand, the bottom was covered with a layer of mud mixed with sand. Biff felt around carefully. Both boys were wearing thick rubber gloves to protect their hands against the sharp, jagged oyster shells.

As Biff was feeling around in the mud, Derek swam over to him. He held a large oyster in front of Biff’s mask. Then he plopped it in his basket.

Biff’s hand touched a large shell. He dug it out and discarded it. It was a clam. He ran into a nest of oysters. He quickly filled his basket and gave the signal to haul up. Minutes later, the basket came down, swaying in the water at the bottom of the line.

The boys worked slowly, carefully, feeling their way. Every so often, a large fish would swim up to them, coming right to the face masks as if to ask, “What are _you_ doing down here?”

Biff kept a sharp check on his watch. He knew his air tank had sufficient air to remain submerged for one hour. It also had a five-minute emergency supply in addition. Biff had no intention of waiting until he had to use the extra air. After being down fifty-five minutes, he signaled Derek. With his forefinger, he pointed upward. Derek got the idea. The boys began their slow ascent.

Rising, looking up toward the surface, they could see the dory outlined above, a fat, cigar-shaped blob.

Breaking water as they surfaced, each boy grabbed the dory’s gunwale. They were both tired. Neither had realized how the water pressure at forty-five feet had sapped their strength. They had been down nearly an hour.

“You don’t know what a tough job diving is until you’ve been down for a good spell,” Charlie said. He leaned over the side and helped the boys into the boat.

They took off their diving equipment.

“Had enough for today, boys?” Biff’s uncle inquired.

“Oh, no. We’ll go down again. After we rest,” Biff replied. “All right with you, Derek?”

Derek nodded his head.

“Actually, I don’t see much point in going back down,” Uncle Charlie said. “We’ve got ten baskets of oysters. We might as well shuck them and see if we find any pearls. If we don’t, then we’ll say good-by to this spot and try another tomorrow.”

“Now I like that idea,” Biff said and stretched out on the narrow seat that ran around the side of the dory.

His uncle upped anchor, and they headed back to their island camp.

They didn’t go into Trinité that day, since they still had the reserve tank of compressed air and enough food for supper. The afternoon was spent at the tedious job of opening oysters. It was slow going. None of the three had the skill of a professional oyster opener.

The job was totally unrewarding.

“Not one pearl.” Biff sighed.

“Not even a single tiny one,” Derek said sadly.

“Now, don’t be downhearted, boys,” Uncle Charlie said, trying to cheer them up. “Can’t expect to hit it the first day.”

“At any rate, we’ve got enough oysters to make a stew. If we had some milk,” Biff said.

“Afraid not, Biff.”

“Yeah. Where are we going to get milk? A seacow, maybe? Wish we’d kept some of them. We could have had an oyster roast.”

“Wrong again, Biff,” Charlie said. “Pearl oysters aren’t edible. These would make you so sick, you wouldn’t be any good for ten days.”

“What a waste!” Biff said, and stretched out on the sand. Every muscle, every bone in his body ached.

All three went to bed that night right after supper.

Biff, having slept heavily, awoke just as dawn broke. He thought he had been awakened by the sound of a boat’s motor. He listened intently. No sound. Biff turned over on his narrow cot, determined to get back to sleep. He was just drifting off when he heard a sound outside the tent, just beyond where his cot touched the inside of the tent wall.

He waited tensely. The sound was only a faint rustle. He saw the side of the tent stretch as if something was crawling underneath it. Biff raised himself on one elbow, ready to sound the alarm.

As he watched, in the faint dawn light, a thick, snake-shaped object slithered up between his cot and the tent’s side.