"All right. Rick, we still don't know for sure, do we? About the people in the houseboat?"

"Not for sure. But we have a pretty good idea. How else would Dad get drugged?"

"Mightn't they have given him a sedative?" Jan asked. "That would have the same effect."

Rick hadn't thought of that. He admitted it was possible.

"I wish the radio trick had worked," Barby said sadly. "I wish we had some way of getting a radio on the houseboat. Then we could listen in on everything they said."

"No way of doing it," Rick said. He was very tired. "Forget it for now and let's all turn in. We can talk some more in the morning."

Steve Ames phoned at five o'clock in the morning. Rick had been sleeping lightly, his rest broken by nightmares that he couldn't remember when he awoke. He got to the phone in the hall. "Just a minute," he said. "Let me get downstairs to the switch."

The entire family was close on his heels as he went into the library.

He threw the scrambler switch, then asked anxiously, "Yes, Steve?"

"Just had word, Rick, so I called in spite of the hour. Your father is safe inside the compound at Los Alamos. He's all right. And just as a precaution, he'll spend most of his time in a shielded area where no radio signal can penetrate. Now go on back to bed and get some sleep."

Rick thanked him gratefully. Los Alamos! That was one of the two main atomic energy weapons laboratories. No place in the United States was more closely guarded. Now he could be sure his father was safe as anyone could be.

He repeated the conversation to his anxious family. "Now," he said, echoing Steve's advice, "let's get back to bed. Perhaps we can really sleep for a change."

He did sleep. It was nearly noon before he awoke. He got up sleepily and found Scotty had just barely preceded him and was now taking a shower.

Downstairs, things were apparently normal. Mrs. Brant and Mrs.

Morrison were at work on lunch, but since an hour was too long to wait, Rick had a bowl of cereal and a gla.s.s of milk. He was careful not to choose Crummies. Scotty settled for three doughnuts and milk.

"Where are the girls?" Rick asked. "Still asleep?"

"They've gone swimming," Mrs. Morrison replied. "They should be back soon, though. They've been gone over an hour."

"I could use a swim myself," Rick admitted.

"Not me," Scotty said. "Wait until afternoon and I'll join you. That cold water would shock me into a state of galloping goose pimples the way I feel now."

Rick had forgotten how cold the water was. "Okay. We'll wait. Let's go over to the lab and take down the lights. I want to clean up the trash cans, too."

They walked leisurely over to the laboratory and stopped for a moment to chat with Joe Blake. Then, before starting on the lights, they walked around behind the lab building.

The laboratories were built on a promontory that sloped inland toward Pirate's Field, which was just above sea level. The raised area ran around the seaward side of the island, so that the Brant house was on high land, too. On the north side, the land sloped down toward the boat landing.

Rick stood on the edge of the low cliff and looked for Barby and Jan.

They weren't in sight.

"They must be using lungs," Scotty said. "Watch for bubbles."

No bubbles were visible, either. Rick checked carefully and began to worry. It was a calm day with little wave action, and the bubbles from the lungs should have been clearly visible. Surely they wouldn't swim so far the bubbles couldn't be seen on a day like this.

"Let's check," Rick said.

The boys hurried to the room where the Scuba equipment was kept. Two lungs and the blue and white equipment were gone. So was the cart. A quick look at Pirate's Cove showed no cart in sight.

Where could they have gone? The boys hurried to the front of the lab building again and found Joe Blake still getting a bit of sunshine.

"Did you see the girls?" Rick asked hurriedly.

Joe nodded. He motioned across the island. "They came and got aqualungs and hauled the cart across to the north side. They're probably swimming over there."

Rick doubted it. He doubted it very much. The currents on the north side kept the bottom stirred up and visibility was too poor for diving.

Without the need of exchanging a word, Rick and Scotty were suddenly running. As they pa.s.sed the house Rick had a sudden thought. He went in and ran up the stairs to his room, grabbed his radio unit and turned it on.

"Barby!" he called frantically. "Barby!"

There was no answer. Tucking the unit into his pocket, he ran out and joined Scotty again. If Barby had her set she wasn't using it.

"Come on." He led the way to the boat cove and stopped short. The speedboat was there, and so was the Scuba cart, but the rowboat wasn't. Anxiously he scanned the water. There was no sign of the girls.

Where were they? Where? The thought struck him. He remembered Barby's comment of the night before.

_Had they gone to the houseboat?_

CHAPTER XVII

Pointer to Disaster

Scotty ran to the speedboat and yelled, "Come on!"

"Wait!" Rick called. "Let's not go barging off without knowing what we're doing."

Scotty turned, puzzled. "What do you mean?"

"The girls have some kind of plan, and we don't know what it is. If we go barging around in the speedboat, we might throw a monkey wrench into the works."

"But we can't just stand here and do nothing," Scotty said desperately.

"We won't. Go get the plane warmed up and wait for me."

Rick hurried into the house and ran up the stairs to Barby's room.

Working fast, he went through the dresser, then through the shelves in her closet. Not finding what he wanted, he paused to look around in case he might have overlooked a possibility.

He didn't know where girls kept things, and he suspected that sometimes the places weren't the same as boys might pick. But he could see no possible place that he hadn't searched.