"We picked him up, but he didn't know a thing. The barber paid him in free haircuts to keep track of people coming and going from the fourth floor. That's all. He didn't know why."

Joe Blake came in the door. "Motor whaleboat coming, Steve. Shall we take the prisoners to the landing?"

"Yes, Joe. Please."

Barby looked at Steve speculatively. "How about the houseboat?"

"Well, how about it? Haven't you seen enough of it?"

Barby smiled. "It would be very nice, if it were only another color.

What will happen to it?"

"A coastguardman will be after it tomorrow. It will be impounded for a while. After that it may be sold for public auction, or it may revert to the owner's estate. It depends on the court."

Barby looked a little disappointed. "Oh, well, we don't really need a houseboat, anyway."

The group broke up as Joe and his partner walked the prisoners across the island to the landing. In a short time the motor whaleboat was speeding to the horizon where a cutter waited.

Rick took a last look. That just about closed the case. The remaining details probably would never be known to the Spindrift group.

"Can't anything be done for Dr. Marks and the other scientists?" he asked Parnell Winston.

Winston shook his head. "No, Rick. We're afraid to tamper, for fear of making things worse. But I neglected to tell you one very important item. The first scientist stricken is becoming rational again, or at least we hope so. Yesterday he asked for food. A short time later he picked up a pencil and paper and began to work out an equation, one connected with the project. Apparently the equation was the last thing he had been working on when the mind reader struck. So we hope and believe that nature is healing the damage. There is no evidence of tissue destruction, so perhaps complete recovery is possible. It's a question of waiting and watching."

Within two weeks Rick had an opportunity to see for himself, because the two scientists from Washington joined the Spindrift group. They were fully recovered, with only vague memories of the period when their minds were not functioning. And Dr. Marks was reported well on the way to normalcy.

The project was almost at an end, with only a few final checks needed on the critical equations. The Morrisons had already set a day for their departure--to Barby's great unhappiness.

As Barby said at dinner one night, "I didn't realize how lonely it gets sometimes without another girl on the island. Until Jan came, that is. Now she's going, and I wish she weren't."

"I'd love to stay," Jan said. "Really I would."

Hartson Brant arrived in time to hear the last exchange. He had left the table briefly to take a phone call. "I'm afraid it's going to be pretty quiet on Spindrift," he agreed. "It looks as though we'll be losing Rick and Scotty for a while!"

Barby wailed, "Not again! Why can't they stay home for a while?"

Rick and Scotty had looked up with quick interest at the scientist's words.

"We've been home for weeks," Rick replied. His eyes were on the slip of paper in his father's hand. "Dad, what is it? Where are we going?"

"Read it aloud," Hartson Brant suggested. He handed Rick the slip.

Rick scanned it quickly. It was a telegram that his father had taken over the phone. Rick's pulse quickened. Dr. Gordon, who had been at work on a secret rocket project in the far west, had wired:

ARRIVING TOMORROW. NEED RICK AND SCOTTY FOR SPECIAL WORK.

URGE THEY BE READY TO DEPART IN THREE DAYS EQUIPPED FOR EXTENDED STAY AT DESERT BASE.

Rick's eyes met Scotty's as he finished reading. "Desert base," he repeated.

Scotty grinned his delight. "John Gordon's rocket base is in the desert. He must want us there."

"But why?" Barby demanded. "You're not rocket experts. Why, even when we had the moon rocket here, you didn't work on the rocket itself."

That was perfectly true. Rick shrugged. "You know as much as we do, Sis."

Hartson Brant stirred his coffee thoughtfully. "I have a hunch," he said. "From the tone of the wire, I suspect John is in some kind of difficulty. Surely he doesn't want you as technicians, but it's not beyond the bounds of possibility that he needs a little detective work done."

It made sense to Rick. But what kind of detective work could he and Scotty do at a highly guarded and secret government base? He fought down the impulse to run up to his room and start packing. Gordon had said in three days. There was plenty of time. Except that Rick knew he'd be dizzy with wondering until John Gordon gave them more information.

The Morrisons rose to the occasion beautifully. "We wouldn't want Barby to be without any companions of her own age here," Mrs. Morrison said quickly. "If it's all right, I'm sure we can let Jan remain until the boys return."

The girls beamed without saying a word, then they broke into excited chatter. Rick and Scotty retired to the front porch and grinned at each other.

"If Dad is right, this is going to be plenty of fun," Scotty said happily. "I've always wanted to get close to the big rockets."

"We'll find out," Rick said. "And if John Gordon has a mystery, we're the pair who can solve it for him."

Later, Rick's words returned to him under the most unusual and terrifying circ.u.mstances of his entire life. The story of the project that led to Rick's greatest adventure will be told in the next Rick Brant Science-Adventure mystery.

_The_ RICK BRANT SCIENCE-ADVENTURE _Stories_

BY JOHN BLAINE

THE ROCKET'S SHADOW

THE LOST CITY

SEA GOLD

100 FATHOMS UNDER

THE WHISPERING BOX MYSTERY

THE PHANTOM SHARK

SMUGGLERS' REEF

THE CAVES OF FEAR

STAIRWAY TO DANGER

THE GOLDEN SKULL

THE WAILING OCTOPUS