"Change in plans. I came straight from Washington to the field and Morrie took off as soon as I arrived. The ship was ready, so we brought it out ourselves, and saved about five hundred bucks in ferry pilot charges." "Everything on the beam in Washington?" Ross asked anxiously.

"Yes, with the help of the association's legal department. Got some papers for each of you to sign. Let's not stand here beating our gums. Ross, you and I start on the shield right away. After we eat."

"Good enough."

Ross and the doctor spent three days on the hard, dirty task of tearing out the fuel system to the tail jets. The nose and belly jets, used only in maneuvering and landing, were left unchanged. These operated on aniline and nitric fuel; Cargraves wanted them left as they were, to get around one disadvantage of atomic propulsion-the relative difficulty in turning the power off and on when needed.

As they worked, they brought each other up to date. Ross told him about the man who had tangled with a dud land mine. Cargraves paid little attention until Ross told him about the crates that had been opened. Cargraves laid down his tools and wiped sweat from his face. "I want the details on that," he stated.

"What's the matter, Doc? Nothing was hurt."

"You figure the dead man had been breaking into the stuff?"

"Well, I thought so until I remembered that the Ranger had said flatly that this bozo was already buzzard meat before our stuff arrived."

Cargraves looked worried and stood up. "Where to, Doc?"

"You go ahead with the job," the scientist answered absently. "I've got to see Art."

Ross started to speak, thought better of it, and went back to work.

"Art," Cargraves started in, "what are you and Morrie doing now?"

"Why, we're going over his astrogation instruments. I'm tracing out the circuits on the acceleration integrator. The gyro on it seems to be off center, by the way."

"It has to be. Take a look in the operation manual. But never mind that. Could you rig an electric-eye circuit around this place?"

"I could if I had the gear."

"Never mind what you might do ‘if'—what can you do with the stuff you've got?"

"Wait a minute, Uncle Don," the younger partner protested. "Tell me what you want to do—I'll tell you if I can wangle it."

"Sorry. I want a prowler circuit around the ship and cabin. Can you do it?"

Art scratched his ear. "Let me see. I'd need photoelectric cells and an ultraviolet light. The rest I can piece together. I've got two light meters in my photo kit; I could rig them for the cells, but I don't know about UV light. If we had a sun lamp, I could filter it. How about an arc? I could jimmy up an arc."

Cargraves shook his head. "Too uncertain. You'd have to stay up all night nursing it. What else can you do?"

"Mmmm... . Well, we could use thermocouples maybe. Then I could use an ordinary floodlight and filter it down to infra-red."

"How long would it take? Whatever you do, it's got to be finished by dark, even if it's only charging the top wire of the fence."

"Then I'd better do just that," Art agreed, "if that—Say!"

"Say what?"

"Instead of giving the fence a real charge and depending on shocking anybody that touches it, I'll just push a volt or two through it and hook it back in through an audio circuit with plenty of gain. I can rig it so that if anybody touches the fence it will howl like a dog. How's that?"

"That's better. I want an alarm right now. Get hold of Morrie and both of you work on it." Cargraves went back to his work, but his mind was not on it. The misgivings which he had felt at the time of the mystery of the missing ‘blunt instrument' were returning. Now more mysteres—his orderly mind disliked mysteries.

He started to leave the rocket about an hour later to see how Art was making out. His route led him through the hold into the pilot compartment. There he found Morrie. His eyebrows went up. "Hi, sport," he said. "I thought you were helping Art."

Morrie looked sheepish. "Oh, that!" he said. "Well, he did say something about it. But I was busy." He indicated the computer, its cover off.

"Did he tell you I wanted you to help him?"

"Well, yes—but he didn't need my help. He can do that sort of work just as well alone."

Cargraves sat down. "Morrie," he said slowly, "I think we had better have a talk. Have you stopped to think who is going to be second-in-command of this expedition?"

Morrie did not answer. Cargraves went on. "It has to be you, of course. You're the other pilot. If anything happens to me the other two will have to obey you. You realize that?"

"Art won't like that." Morrie's voice was a mutter.

"Not as things stand now. Art's got his nose out of joint. You can't blame him—he was disappointed that he didn't get to take pilot training, too."

"But that wasn't my fault."

"No, but you've got to fix it. You've got to behave so that, if the time comes, they'll want to take your orders. This trip is no picnic. There will be times when our lives may depend on instant obedience. I put it to you bluntly, Morrie—if I had had a choice I would have picked Ross for my second-incommand—he's less flighty than you are. But you're it, and you've got to live up to it. Otherwise we don't take off."

"Oh, we've got to take off! We can't give up now!"

"We'll make it. The trouble is, Morrie," he went on, "American boys are brought up loose and easy. That's fine. I like it that way. But there comes a time when loose and easy isn't enough, when you have to be willing to obey, and do it wholeheartedly and without argument. See what I'm driving at?"

"You mean you want me to get on back to the shop and help Art."

"Correct." He swung the boy around and faced him toward the door, slapped him on the back and said, "Now git!"

Morrie "got." He paused at the door and flung back over his shoulder,

"Don't worry about me, Doc. I can straighten out and fly right."

"Roger!" Cargraves decided to have a talk with Art later.

Chapter 6 - DANGER IN THE DESERT

THE SPACE SUITS WERE delivered the next day, causing another break in the work, to Cargraves' annoyance. However, the boys were so excited over this evidence that they were actually preparing to walk on the face of the moon that he decided to let them get used to the suits.

The suits were modified pressurized stratosphere suits, as developed for the air forces. They looked like diving suits, but were less clumsy. The helmets were "goldfish bowls" of Plexiglas, laminated with soft polyvinyl-butyral plastic to make them nearly shatter-proof. There were no heating arrangements. Contrary to popular belief, vacuum of outer space has no temperature; it is neither hot nor cold. Man standing on the airless moon would gain or lose heat only by radiation, or by direct contact with the surface of the moon. As the moon was believed to vary from extreme sub-zero to temperatures hotter than boiling water, Cargraves had ordered thick soles of asbestos for the shoes of the suits and similar pads for the seats of the pants of each suit, so that they could sit down occasionally without burning or freezing. Overgloves of the same material completed the insulation against contact. The suits were so well insulated, as well as air-tight, that body heat more than replaced losses through radiation. Cargraves would have preferred thermostatic control, but such refinements could be left to the pioneers and colonists who would follow after. Each suit had a connection for an oxygen bottle much larger and heavier than the jump bottle of an aviator, a bottle much too heavy to carry on earth but not too heavy for the surface of the moon, where weight is only one-sixth that found on earth.

The early stratosphere suits tended to starfish and become rigid, which made the simplest movements an effort. In trying on his own suit, Cargraves was pleased to find that these suits were easy to move around in, even when he had Ross blow him up until the suit was carrying a pressure of three atmospheres, or about forty-five pounds to the square inch. The constant-volume feature, alleged for the de-Camp joints, appeared to be a reality.