Tinker piped up, "Now that you mention it, there's been a rumor about somebody running a still back at the base."

"A still?" Paul snapped.

"An active still," Tinker replied.

"Nothing but rumor," said Wojo. "Where would somebody hide a still?"

Paul had to turn almost sideways to peer around the edge of his helmet and look at Wojo's face. The man avoided his gaze.

"What do you use for ingredients?" he asked.

"Search me," Wojo replied innocently. "I'm no chemist"

"There's plenty of exotic chemicals available," Tinker said, "from the labs and the pharmacy. From what I've heard, they might even be using some of the residual rocket propellants left in the landers' tanks."

"This had better be a joke," Paul muttered. "Making booze and stealing rocket propellants isn't just criminal, it's goddamned dangerous."

"It's a joke," Wojo assured him.

Tinker laughed. "We got you that time, boss boss."

Paul made himself laugh with them. But he was thinking that a drunk could kill a lot of people very suddenly at Moonbase. Better look into this joke when I get back.

It was night and would remain so for seventy-five hours more. Yet the broad rock-strewn plain of Mare Nubium was clearly lit by Earthglow. Once Wojo resumed the driving chore Paul leaned as far back as he could and watched the big blue and white crescent of Earth hanging in the dark cold sky. It was in the gibbous phase, fatter than a half-Earth, glowing warm and beautiful out there.

When the Earth was in its 'new' phase, Paul could trace out the cities and highways from the lights shining in the darkened globe. But now the glare from its daylit side drowned out the night lights.

Anyway, Paul said to himself, we've got work to do. We're not here for the sightseeing.

"There's the spot," Wojo said, slowing the tractor to a stop.

Paul looked at the electronic map on the control panel. The blue dot marking their location was touching the red dot marking the test site.

"Check it out with the GPS signal," Paul said.

"Already did," Wojo answered* 'Last fix we'll get for a while. Feeble-minded little satellite's sinking below the horizon and there won't be another in sight for a couple hours."

Tinker helped them offload the equipment and while he and Paul set up a plastic bubble tent for their quarters, Wojo used the tractor's front blade to dig a trench big enough to hold a full-sized shelter.

"Now we see what these teeny bugs can do," Wojo said. There were three sets of nanomachines, each sealed in an insulated cylindrical container that looked to Paul like a high-tech metallic thermos bottle. Using the tractor's communications system he established a link with Cardenas in San Jose, beaming a signal directly to a commsat in synchronous orbit above the Pacific.

The signal was weak, but Paul had Cardenas on-line as Wojo pried open the first container and gingerly carried it to the trench.

"Feel kinda like Aladdin," Wojo muttered. "Where's the puff of smoke and the genie?"

Cardenas took him seriously. "You won't see anything for at least two hours," she said. "Just drop the container into the trench." Paul could see tension in her face. And excitement.

Tinker spent the next two hours checking out the ambient levels of microwave radiation in the area, setting out a series of pocket-sized detectors on the dusty regolith. Wojo hauled equipment off the tractor and set up their quarters inside the plastic bubble tent.

Paul watched the trench. "Nothing seems to be happening," he said.

Three seconds later Cardenas's streaky image replied, "The nanomachines are reproducing themselves. Everything's going according to the program."

Carrying a portable communicator in his gloved hand, Paul walked over to the edge of the trench. Nothing was stirring. It's going to be a long two hours, he told himself.

Wojo came up beside him. Paul was staring so intently into the empty trench that he only noticed Wojo's presence when he heard the man's labored breathing through his earphones.

"You're out of condition," Paul said.

"Easy thing to do, up here," Wojo admitted.

"Better check with the medical people, let them set up an exercise routine for you." It was a requirement in every employee's contract; if an employee did not follow the medical department's prescribed exercise regimen, it was grounds for return to Earth and perhaps even dismissal from the company.

"Right." There were a thousand ways to evade the exercising, both Wojo and Paul knew.

Tinker joined them. "I'm all finished with my work. Can we go home now?"

Paul ignored him.

At first he wasn't certain he actually saw it. Paul wanted to rub his eyes, but inside the spacesuit and helmet he couldn't. Yet it looked as if a tiny pool of something shiny had formed on the bottom of the trench, right where the opened container was lying. A puddle that looked almost like glassy, shining liquid mercury.

"Am I seeing straight?" Wojo asked.

"Yeah," said Paul. "Look! It's spreading."

A glassy smooth film of titanium was growing across the bottom of the trench. And its sides. Fascinated, Paul watched for hours as the titanium shell slowly arched above the surface of the regolith to form a complete cylinder. Then its ends began to close.

"The next set of bugs is the real test," Cardenas said, looking much happier and more relaxed now.

"The airlock," Paul said. If they can build a whole airlock by themselves, they can build just about anything, he thought Wojo carried the second cylinder to the open doorway of the titanium shelter with a good deal more confidence than he had borne the first.

They took turns going inside the pressurized bubble tent to grab a bite of dinner. Paul could hardly tear himself away from watching an, airlock assemble itself, as if by magic, literally from the ground up.

Now give them a few hours to fill the shelter with oxygen," Cardenas said, positively glowing once the airlock was finished, "and you'll have a complete prefabricated, ready-to-use shelter built entirely out of native materials by my nanomachines."

The three men slept inside the pressurized tent, in their suits. It was uncomfortable. They could not lie down; the best they could do was to lean back against rests they had brought with them, reclining at roughly a forty-five degree angle. If the tent were suddenly ruptured they could snap down their visors and turn on their backpack life support systems in a second or two.

To make it worse, Tinker either would not or could not stop making puns. Paul groaned and Wojo threatened the astronomer's life, but no matter what either of them said, Tink turned it into a maddening pun. They became very elaborate as the men prepared for sleep, climaxing with a pun based on the fact that making bowel movements in a spacesuit is a complex and miserable business.

"What we need is a special container, maybe two pints in capacity," Tink merrily chattered away. "I think I'll enter a class-action suit to force the corporation to supply us with special bottles for manure storage."

"Tink...' Wojo growled menacingly.

Undeterred, the astronomer concluded, "Yes, sir, that's what I'll do. Bring my request to a judge and see if he'll demand ordure in the quart."

Before Wojo could throw anything, Paul said, "Okay, Tink. That's enough. Not another word out of you."

Tinker looked from Paul to Wqjo and back again. The self-satisfied grin on his face faded a little. His eyes lit up as if he had thought of still another pun.

"No!" Paul said sharply, the way he would to a baby he was trying to train. Or a dog.

Tink nodded inside his helmet and pressed an upraised finger to his lips. Wojo, still looking grim, nodded his thanks to Paul.

Paul thought he would be unable to sleep, propped up inside the suit and excited about the nanomachines working away, silent and invisible out there. But he drifted off almost as soon as he closed his eyes, and if he dreamed at all he remembered none of it when he awoke a few hours later, long before his suit's alarm was set to go off.

Wojo was snoring like an asthmatic ox and Tinker was muttering in his sleep. Paul quietly refilled his backpack oxygen supply from the tanks in the tent, then slid his visor down and stepped through the tent's minimal airlock.

The shelter gleamed slightly in the Earthlight, its curved top uncovered as yet by protective dirt. Paul grappled one of the nitrogen tanks from the tractor's back and hauled it to the shelter. He examined the airlock's control panel. It was mechanical rather than electronic; rather crude but a good-enough test of the.nanomachines' abilities. Cardenas had a team working on electronic assemblies, but Greg had wanted to go ahead with this test as quickly as possible and Paul had agreed with him.

He slid the outer hatch open, lugged the nitrogen cylinder inside and then stepped in himself and pulled the hatch closed. A set of four knobs projected from one side of the inner hatch. Paul turned the top one and soon heard the reassuring hiss of gas filling the airlock. Once the sound stopped he took a pressure gauge from his belt. Less than two psi, but holding steady. Oxygen pressure wasn't as high as it should be, not yet, but at least the airlock didn't seem to be leaking.

Is it really oxygen? Paul asked himself. The little portable mass spectrograph was still in the tractor. He'd have to assume the bugs were doing their work properly. For now.

Opening the inner airlock hatch, Paul stepped inside the shelter. In the light from his helmet lamp, the curving walls glistened almost as if they were wet. The pressure gauge held steady. The shelter was airtight. Paul dragged the nitrogen cylinder into the empty shelter and opened its valve. By noon tomorrow we'll be able to sit in here in our shirtsleeves, he thought happily.

"We'll eat lunch in here," he promised himself aloud. Paul and Tink spent the morning hauling equipment into the new shelter, while Wojo worked the tractor, carefully piling up rubble over its curving roof.

At last, a few minutes after noon, the three of them entered the shelter.

For a long moment they simply stood inside the cylindrical space. The walls still glistened as if newborn. The bunks, table and equipment they had carried in looked shiny new, never; used. Tinker held the mass spectrometer in his gloved hands.

"Well?" Paul asked him.

Peering at the readout display, Tinker said, "Seventy-six percent oxygen, twenty-four nitrogen."

"Good enough," Paul said.

"Pressure's just a tad over five psi," Wojo said.

"Okay." Paul slid his visor up and took a deep breath. "It's not the Garden of Eden, but it'll do."

With great relief they peeled themselves out of their spacesuits, although the stench of bodies confined inside the suits for several days was less than pleasant.

"I won't mention yours if you don't mention mine," Wojo said, pinching his nose with forefinger and thumb.

"Okay," Tinker answered happily. "Let's not make a stink about it."

Paul understood how a man could be driven to murder.

They ate lunch in their coveralls at the small table they had carried in, after heating the prepackaged meals in the microwave cooker. Tinker seemed very impressed with the nanomachines' achievement.

"We could build a radio telescope facility on the farside!" he said enthusiastically. "These bugs are going to change everything we do up here!"

Wojo chewed his soyburger thoughtfully, then replied, "Better make sure this shelter really works right before you go prancing off to the farside."

"Oh, you want to work the bugs out of it?" Tinker asked, delightedly.

Wojo looked as if he wanted to spit After lunch Paul checked in with Kris Cardenas to assure her that all was going well. Then he patched through a call to Joanna. She was at home, in her sitting room.

"Are you okay?" were the first words out of Paul's mouth when he saw her stretched out on the chintz-covered chaise longue.

It took three seconds for her to smile. "Of course I'm all right."

"Oh, I thought maybe you didn't feel well."

Again the delay. Then, "Paul, it's seven-thirty in the morning here. I've been trying to call you for more than an hour."

"Call me? Why?"

Joanna's face clouded once Paul's question reached her. "It's Greg... I told him about the baby last night."

"He wasn't pleased, I guess."

"He got hysterical. He frightened me."

Paul felt his insides tensing.

Joanna went on, "He started raving about how we're trying to get rid of him, push him out of the corporation. Lord, he sounded like his father."

"I'm not trying to push him out," Paul said.

Joanna continued, "He said something about getting rid of Brad. As if he did it deliberately."

"Brad?"

Without a pause, she went on, "And he's furious with you. He said he's going to destroy you. He said you'd never come back from the Moon."

Paul saw the anguish in her face. The fear. For which of us? he wondered. Is she scared for me or is she scared that Greg's getting beyond her control?

"Paul, he's violent!"

"He didn't hurt you, did he?"

The three-second lag seemed like an infinity. At last Joanna shook her head wearily. "No, but he was boiling with anger about you. And the baby. It was frightening."

So all Greg's smiles and cooperation were just a front, after all, Paul thought. He said to his wife, "As long as he's not threatening you, it's okay."

"He wants to kill you!" she blurted.

Paul made himself smile reassuringly. "Well, he'll have to wait until I get back for that, won't he? He can't reach me up here."

Joanna nodded, but she still looked fearful.

TEMPO 20(N).

Later that afternoon Paul got two warnings of danger simultaneously.

He had officially'dedicated' their new shelter while they ate lunch, using a sprinkle of water instead of champagne to dub it Tempo 20(N): the twentieth'temporary' shelter erected by Moonbase. The (N) designated that it had been built by nanomachines.