Stephen Demerest looked at the textured sky. He kept looking at it and found the blue opaque and revolting.

Unwarily, he had looked at the Sun, for there was nothing to blank it out automatically, and then he had snatched his eyes away in panic. He wasn't blinded; just a few afterimages. Even the Sun was washed out.

Involuntarily, he thought of Ajax's prayer in Homer's Iliad. They were fighting over the body of Patroclus in the mist and Ajax said, "O Father Zeus, save the Achaeans out of this mist! Make the sky clean, grant us to see with our eyes! Kill us in the light, since it is thy pleasure to kill us!"

Demerest thought: Kill us in the light-

Kill us in the clear light on the Moon, where the sky is black and soft, where the stars shine brightly, where the cleanliness and purity of vacuum make all things sharp.

-  Not in this low-clinging, fuzzy blue.

He shuddered. It was an actual physical shudder that shook his lanky body, and he was annoyed. He was going to die. He was sure of it. And it wouldn't be under the blue, either, come to think of it, but under the black-but a different black.

It was as though in answer to that thought that the ferry pilot, short, swarthy, crisp-haired, came up.to him and said, "Ready for the black, Mr. Demerest?"

Demerest nodded. He towered over the other as he did over most of the men of Earth. They were thick, all of them, and took their short, low steps with ease. He himself had to feel his footsteps, guide them through the air; even the impalpable bond that held him to the ground was textured.

"I'm ready," he said. He took a deep breath and deliberately repeated his earlier glance at the Sun. It was low in the morning sky, washed out by dusty air, and he knew it wouldn't blind him. He didn't think he would ever see it again.

He had never seen a bathyscaphe before. Despite everything, he tended to think of it in terms of prototypes, an oblong balloon with a spherical gondola beneath. It was as though he persisted in thinking of space flight in terms of tons of fuel spewed backward in fire, and an irregular module feeling its way, spiderlike, toward the Lunar surface.

The bathyscaphe was not like the image in his thoughts at all. Under its skin, it might still be buoyant bag and gondola, but it was all engineered sleekness now.

"My name is Javan," said the ferry pilot. "Omar Javan."

"Javan?"

"Queer name to you? I'm Iranian by descent; Earthman by persuasion. Once you get down there, there are no nationalities." He grinned and his complexion grew darker against the even whiteness of his teeth. "If you don't mind, we'll be starting in a minute. You'll be my only passenger, so I guess you carry weight."

"Yes," said Demerest dryly. "At least a hundred pounds more than I'm used to."

"You're from the Moon? I thought you had a queer walk on you. I hope it's not uncomfortable."

"It's not exactly comfortable,,but I manage. We exercise for this."

"Well, come on board." He stood aside and let Demerest walk down the gangplank. "I wouldn't go to the Moon myself."

"You go to Ocean-Deep."

"About fifty times so far. That's different."

Demerest got on board. It was cramped, but he didn't mind that. It might be a space module except that it was more-well, textured. There was that word again. There was the clear feeling everywhere that mass didn't matter. Mass was held up; it didn't have to be hurled up.

They were still on the surface. The blue sky could be seen greenishly through the clear thick glass. Javan said, "You don't have to be strapped in. There's no acceleration. Smooth as oil, the whole thing. It won't take long; just about an hour. You can't smoke."

"I don't smoke," said Demerest.

"I hope you don't have claustrophobia."

"Moon-men don't have claustrophobia."

"All that open-"

"Not in our cavern. We live in a"-he groped for the phrase -"a Lunar-Deep, a hundred feet deep."

"A hundred feet!" The pilot seemed amused, but he didn't smile. "We're slipping down now."

The interior of the gondola was fitted into angles but here and there a section of wall beyond the instruments showed its basic sphericity. To Javan, the instruments seemed to be an extension of his arms; his eyes and hands moved over them lightly, almost lovingly.

"We're all checked out," he said, "but I like a last-minute look-over; we'll be facing a thousand atmospheres down there." His finger touched a contact, and the round door closed massively inward and pressed against the beveled rim it met.

"The higher the pressure, the tighter that will hold," said Javan. "Take your last look at sunlight, Mr. Demerest."

The light still shone through the thick glass of the window. It was wavering now; there was water between the Sun and them now.

"The last look?" said Demerest.

Javan snickered. "Not the last look. I mean for the trip...I suppose you've never been, on a bathyscaphe before."

"No, I haven't. Have many?"

"Very few," admitted Javan. "But don't worry. It's just an underwater balloon. We've introduced a million improvements since the first bathyscaphe. It's nuclear-powered now and we can move freely by water jet up to certain limits, but cut it down to basics and it's still a spherical gondola under buoyancy tanks. And it's still towed out to sea by a mother ship because it needs what power it carries too badly to waste it on surface travel. Ready?"

"Ready."

The supporting cable of the mother ship flicked away and the bathyscaphe settled lower; then lower still, as sea water fed into the buoyancy tanks. For a few moments, caught in surface currents, it swayed, and then there was nothing. The bathyscaphe sank slowly through a deepening green.

Javan relaxed. He said, "John Bergen is head of Ocean-Deep. You're going to see him?"

"That's right."

"He's a nice guy. His wife's with him."

"She is?"

"Oh, sure. They have women down there. There's a bunch down there, fifty people. "Some stay for months."

Demerest put his finger on the narrow, nearly invisible seam where door met wall. He took it away and looked at it. He said, "It's oily."

"Silicone, really. The pressure squeezes some out. It's supposed to...Don't worry. Everything's automatic. Everything's fail-safe. The first sign of malfunction, any malfunction at all, our ballast is released and up we go."

"You mean nothing's ever happened to these bathyscaphes?"

"What can happen?" The pilot looked sideways at his passenger. "Once you get too deep for sperm whales, nothing can go wrong."

"Sperm whales?" Demerest's thin face creased in a frown.

"Sure, they dive as deep as half a mile. If they hit a bathyscaphe-well, the walls of the buoyancy chambers aren't particularly strong. They don't have to be, you know. They're open to the sea and when the gasoline, which supplies the buoyancy, compresses, sea water enters."

It was dark now. Demerest found his gaze fastened to the viewport. It was light inside the gondola, but it was dark in that window. And it was not the darkness of space; it was a thick darkness.

Demerest said sharply, "Let's get this straight, Mr. Javan. You are not equipped to withstand the attack of a sperm whale. Presumably you are not equipped to withstand the attack of a giant squid. Have there been any actual incidents of that sort?"

"Well, it's like this-"

"No games, please, and don't try ragging the greenhorn. I am asking out of professional curiosity. I am head safety engineer at Luna City and I am asking what precautions this bathyscaphe can take against possible collision with large creatures."

Javan looked embarrassed. He muttered, "Actually, there have been no incidents."

"Are any expected? Even as a remote possibility?"

"Anything is remotely possible. But actually sperm whales are too intelligent to monkey with us and giant squid are too shy."

"Can they see us?"

"Yes, of course. We're lit up."

"Do you have floodlights?"

"We're already past the large-animal range, but we have them, and I'll turn them on for you."

Through the black of the window there suddenly appeared a snow-storm, an inverted upward-falling snowstorm. The blackness had come alive with stars in three-dimensional array and all moving upward.

Demerest said, "What's that?"

"Just crud. Organic matter. Small creatures. They float, don't move much, and they catch the light. We're going down past them. They seem to be going up in consequence."

Demerest's sense of perspective adjusted itself and he said, "Aren't we dropping too quickly?"

"No, we're not. If we were, I could use the nuclear engines, if I wanted to waste power; or I could drop some ballast. I'll be doing that later, but for now everything is fine. Relax, Mr. Demerest. The snow thins as we dive and we're not likely to see much in the way of spectacular life forms. There are small angler fish and such but they avoid us."

Demerest said, "How many do you take down at a time?"

"I've had as many as four passengers in this gondola, but that's crowded. We can put two bathyscaphes in tandem and carry ten, but that's clumsy. What we really need are trains of gondolas, heavier on the nukes-the nuclear engines-and lighter on the buoyancy. Stuff like that is on the drawing board, they tell me. Of course, they've been telling me that for years."

"There are plans for large-scale expansion of Ocean-Deep, then?"

"Sure, why not? We've got cities on the continental shelves, why not on the deep-sea bottom? The way I look at it, Mr. Demerest, where man can go, he will go and he should go. The Earth is ours to populate and we will populate it. All we need to make the deep sea habitable are completely maneuverable 'scaphes. The buoyancy chambers slow us, weaken us, and complicate the engineering."

"But they also save you, don't they? If everything goes wrong at once, the gasoline you carry will still float you to the surface-. What would do that for you if your nuclear engines go wrong and you had no buoyancy?"

"If it comes to that, you can't expect to eliminate the chances of accident altogether, not even fatal ones."

"I know that very well," said Demerest feelingly.

Javan stiffened. The tone of his voice changed. "Sorry. Didn't mean anything by that. Tough about that accident."

"Yes," said Demerest. Fifteen men and five women had died. One of the individuals listed among the "men " had been fourteen years old. It had been pinned down to human failure. What could a head safety engineer say after that?

"Yes," he said.

A pall dropped between the two men, a pall as thick and as turgid as the pressurized sea water outside. How could one allow for panic and for distraction and for depression all at once? There were the Moon-Blues-stupid name-but they struck men at inconvenient times. It wasn't always noticeable when the Moon-Blues came but it made men torpid and slow to react.

How many times had a meteorite come along and been averted or smothered or successfully absorbed? How many times had a Moonquake done damage and been held in check? How many times had human failure been backed up and compensated for? How many times had accidents not happened?

But you don't payoff on accidents not happening. There were twenty dead-

Javan said (how many long minutes later?), "There are the lights of Ocean-Deep!"

Demerest could not make them out at first. He didn't know where to look. Twice before, luminescent creatures had flicked past the windows at a distance and with the floodlights off again, Demerest had thought them the first sign of Ocean-Deep. Now he saw nothing.

"Down there," said Javan, without pointing. He was busy now, slowing the drop and edging the 'scaphe sideways.

Demerest could hear the distant sighing of the water jets, steam-driven, with the steam formed by the heat of momentary bursts of fusion power.

Demerest thought dimly: Deuterium is their fuel and it's all around them. Water is their exhaust and it's all around them.

Javan was dropping some of his ballast, too, and began a kind of distant chatter. "The ballast used to be steel pellets and they were dropped by electromagnetic controls. Anywhere up to fifty tons of it were used in each trip. Conservationists worried about spreading rusting steel over the ocean floor, so we switched to metal nodules that are dredged up from the continental shelf. We put a thin layer of iron over them so they can still be electromagnetically handled and the ocean bottom gets nothing that wasn't sub-ocean to begin with. Cheaper, too...But when we get out real nuclear 'scaphes, we won't need ballast at all."

Demerest scarcely heard him. Ocean-Deep could be seen now. Javan had turned on the floodlights and far below was the muddy floor of the Puerto Rican Trench. Resting on that floor like a cluster of equally muddy pearls was the spherical conglomerate of Ocean-Deep.

Each unit was a sphere such as the one in which Demerest was now sinking toward contact, but much larger, and as Ocean-Deep expanded-expanded-expanded, new spheres were added.

Demerest thought: They're only five and a half miles from home, not a quarter of a million.

"How are we going to get through?" asked Demerest.

The 'scaphe had made contact. Demerest heard the dull sound of metal against metal but then for minutes there had been nothing more than a kind of occasional scrape as Javan bent over his instruments in rapt concentration.

"Don't worry about that," Javan said at last, in belated answer. "There's no problem. The delay now is only because I have to make sure we fit tightly. There's an electromagnet joint that holds at every point of a perfect circle. When the instruments read correctly, that means we fit over the entrance door."

"Which then opens?"

"It would if there were air on the other side, but there isn't. There's sea water, and that has to be driven out. Then we enter."

Demerest did not miss this point. He had come here on this, the last day of his life, to give that same life meaning and he intended to miss nothing.

He said, "Why the added step? Why not keep the air lock, if that's what it is, a real air lock, and have air in it at an times?"

"They tell me it's a matter of safety," said Javan. "Your specialty. The interface has equal pressure on both sides at all times, except when men are moving across. This door is the weakest point of the whole system, because it opens and closes; it has joints; it has seams. You know what I mean?"

"I do," murmured Demerest. There was a logical flaw here and that meant there was a possible chink through which-but later.

He said, "Why are we waiting now?"

"The lock is being emptied. The water is being forced out."

"By air."

"Hell, no. They can't afford to waste air like that. It would take a thousand atmospheres to empty the chamber of its water, and filling the chamber with air at that density, even temporarily, is more air than they can afford to expend. Steam is what does it."

"Of course. Yes."

Javan said cheerfully, "You heat the water. No pressure in the world can stop water from turning to steam at a temperature of more than 374 C. And the steam forces the sea water out through a one-way valve."

"Another weak point," said Demerest. "I suppose so. It's never failed yet. The water in the lock is being pushed out now. When hot steam starts bubbling out the valve, the process automatically stops and the lock is fun of overheated steam."

"And then?"

"And then we have a whole ocean to cool it with. The temperature drops and the steam condenses. Once that happens, ordinary air can be let in at a pressure of one atmosphere and then the door opens."

"How long must we wait?"

"Not long. If there were anything wrong, there'd be sirens sounding. At least, so they say. I never heard one in action."

There was silence for a few minutes, and then there was a sudden sharp clap and a simultaneous jerk.

Javan said, "Sorry, I should have warned you. I'm so used to it I forgot. When the door opens, a thousand atmospheres of pressure on the other side forces us hard against the metal of Ocean-Deep. No electromagnetic force can hold us hard enough to prevent that last hundredth-of-an-inch slam."

Demerest unclenched his fist and released his breath. He said, "Is everything all right?"

"The walls didn't crack, if that's what you mean. It sounds like doom, though, doesn't it? It sounds even worse when I've got to leave and the air lock fills up again. Be prepared for that."

But Demerest was suddenly weary. Let's get on with it, he thought. I don't want to drag it out. He said, "Do we go through now?"

"We go through."

The opening in the 'scaphe wall was round and small; even smaller than the one through which they had originally entered. Javan went through it sinuously, muttering that it always made him feel like a cork in a bottle.

Demerest had not smiled since he entered the 'scaphe. Nor did he really smile now, but a comer of his mouth quirked as he thought that a skinny Moon-man would have no trouble.

He went through also, feeling Javan's hands firmly at his waist, helping him through.

Javan said, "It's dark in here. No point in introducing an additional weakness by wiring for lighting. But that's why flashlights were invented."

Demerest found himself on a perforated walk, its stainless metallic surface gleaming dully. And through the perforations he could make out the wavering surface of water.

He said, "The chamber hasn't been emptied."

"You can't do any better, Mr. Demerest. If you're going to use steam to empty it, you're left with that steam, and to get the pressures necessary to do the emptying that steam must be compressed to a~ut one-third the density of liquid water. When it condenses, the chamber remains one-third full of water-but it's water at just one-atmosphere pressure... Come on, Mr. Demerest."

John Bergen's face wasn't entirely unknown to Demerest. Recognition was immediate. Bergen, as head of Ocean-Deep for nearly a decade now, was a familiar face on the TV screens of Earth-just as the leaders of Luna City had become familiar.

Demerest had seen the head of Ocean-Deep both flat and in three dimensions, in black-and-white and in color. Seeing him in life added little.

Like Javan, Bergen was short and thickset; opposite in structure to the traditional (already traditional?) Lunar pattern of physiology. He was fairer than Javan by a good deal and his face was noticeably asymmetrical, with his somewhat thick nose leaning just a little to the right.

He was not handsome. No Moon-man would think he was, but then Bergen smiled and there was a sunniness about it as he held out his large hand.

Demerest placed his own thin one within, steeling himself for a hard grip, but it did not come. Bergen took the hand and let it go, then said, "I'm glad you're here. We don't have much in the way of luxury, nothing that will make our hospitality stand out, we can't even declare a holiday in your honor-but the spirit is there. Welcome!"

"Thank you," said Demerest softly. He remained unsmiling now, too. He was facing the enemy and he knew it. Surely Bergen must know it also and, since he did, that smile of his was hypocrisy.

And at that moment a clang like metal against metal sounded deafeningly and the chamber shuddered. Demerest leaped back and staggered against the wall.

Bergen did not budge. He said quietly, "That was the bathyscaphe unhitching and the waterclap of the air lock filling. Javan ought to have warned you."

Demerest panted and tried to make his racing heart slow. He said, "Javan did warn me. I was caught by surprise anyway."

Bergen said, "Well, it won't happen again for a while. We don't often have visitors, you know. We're not equipped for it and so we fight off all kinds of big wheels who think a trip down here would be good for their careers. Politicians of all kinds, chiefly. Your own case is different of course."

Is it? thought Demerest. It had been hard enough to get permission to make the trip down. His superiors back at Luna City had not approved in the first place and had scouted the idea that a diplomatic interchange would be of any use. ("Diplomatic interchange" was what they had called it.) And when he had overborne them, there had been Ocean-Deep's own reluctance to receive him.

It had been sheer persistence alone that had made his present visit possible. In what way then was Demerest's case different?

Bergen said, "I suppose you have your junketing problems on Luna City, too?"

"Very little," said Demerest. "Your average politician isn't as anxious to travel a half-million-mile round trip as he is to travel a ten-mile one."

"I can see that," agreed Bergen, "and it's more expensive out to the Moon, of course...In a way, this is the first meeting of inner and outer space. No Ocean-man has ever gone to the Moon as far as I know and you're the first Moonman to visit a sub-sea station of any kind. No Moon-man has ever been to one of the settlements on the continental shelf."

"It's a historic meeting, then," said Demerest, and tried to keep the sarcasm out of his voice.

If any leaked through, Bergen showed no sign. He rolled up his sleeves as though to emphasize his attitude of informality (or the fact that they were very busy, so that there would be little time for visitors?) and said, "Do you want coffee? I assume you've eaten. Would you like to rest before I show you around? Do you want to wash up, for that matter, as they say euphemistically?"

For a moment, curiosity stirred in Demerest; yet not entirely aimless curiosity. Everything involving the interface of Ocean-Deep with the outside world could be of importance. He said, "How are sanitary facilities handled here?"

"It's cycled mostly; as it is on the Moon, I imagine. We can eject if we want to or have to. Man has a bad record of fouling the environment, but as the only deep-sea station, what we eject does no perceptible damage. Adds organic matter." He laughed.

Demerest filed that away, too. Matter was ejected; there was therefore ejection tubes. Their workings might be of interest and he, as a safety engineer, had a right to be interested.

"No, he said, "I don't need anything at the moment. If you're busy-"

"That's all right. We're always busy, but I'm the least busy, if you see what I mean. Suppose I show you around. We've got over fifty units here, each as big as this one, some bigger-"

Demerest looked about. Again, as in the 'scaphe, there were angles everywhere, but beyond the furnishings and equipment there were signs of the inevitable spherical outer wall. Fifty of them!

"Built up," went on Bergen, "over a generation of effort. The unit we're standing in is actually the oldest and there's been some talk of demolishing and replacing it. Some of the men say we're ready for second-generation units, but I'm not sure. It would be expensive-everything's expensive down here-and getting money out of the Planetary Project Council is always a depressing experience."

Demerest felt his nostrils flare involuntarily and a spasm of anger shot through him. It was a thrust; surely. Luna City's miserable record with the PPC must be well known to Bergen.

But Bergen went on, unnoticing. "I'm a traditionalist, too-just a little bit. This is the first deep-sea unit ever constructed. The first two people to remain overnight on the floor of an ocean trench slept here with nothing else beyond this bare sphere except for a miserable portable fusion unit to work the escape hatch. I mean the air lock, but we called it the escape hatch to begin with-and just enough controls for the purpose. Reguera and Tremont, those were the men. They never made a second trip to the bottom, either; stayed Topside forever after. Well, well, they served their purpose and both are dead now. And here we are with fifty people and with six months as the usual tour of duty. I've spent only two weeks Topside in the last year and a half."

He motioned vigorously to Demerest to follow him, slid open a door which moved evenly into a recess, and took him into the next unit. Demerest paused to examine the opening. There were no seams that he could notice between the adjacent units.

Bergen noted the other's pause and said, "When we add on our units, they're welded under pressure into the equivalent of a single piece of metal and then reinforced. We can't take chances, as I'm sure you understand, since I have been given to understand that you're the head safe-"

Demerest cut him off. "Yes," he said. "We on the Moon admire your safety record."

Bergen shrugged. "We've been lucky. Our sympathy, by the way, on the rotten break you fellows had. I mean that fatal-"

Demerest cut him off again. "Yes."

Bergen, the Moon-man decided, was either a naturally voluble man or else was eager to drown him in words and get rid of him.

"The units," said Bergen, "are arranged in a highly branched chain-three-dimensional actually. We have a map we can show you, if you're interested. Most of the end units represent living-sleeping quarters. For privacy, you know. The working units tend to be corridors as well, which is one of the embarrassments of having to live down here.

"This is our library; part of it, anyway. Not big, but it's got our records, too, on carefully indexed and computed microfilm, so that for its kind it's not only the biggest in the world, but the best and the only. And we have a special computer to handle the references to meet our needs exactly. It collects, selects, coordinates, weighs, then gives us the gist.

"We have another library, too, book films and even some printed volumes. But that's for amusement."

A voice broke in on Bergen's cheerful flow. "John? May I interrupt?"

Demerest started; the voice had come from behind him. Bergen said, "Annette! I was going to get you. This is Stephen Demerest of Luna City. Mr. Demerest, may I introduce my wife, Annette?"

Demerest had turned. He said stiffly, a little mechanically, "I'm pleased to meet you, Mrs. Bergen." But he was staring at her waistline.

Annette Bergen seemed in her early thirties. Her brown hair was combed simply and she wore no makeup. Attractive, not beautiful, Demerest 'noted vaguely. But his eyes kept returning to that waistline.

She shrugged a little. "Yes, I'm pregnant, Mr. Demerest. I'm due in about two months."

"Pardon me," Demerest muttered. "So rude of me...I didn't-" He faded off and felt as though the blow had been a physical one. He hadn't expected women, though he didn't know why. He knew there would have to be women in Ocean-Deep. And the ferry pilot had said Bergen's wife was with him.

He stammered as he spoke. "How many women are there in Ocean-Deep, Mr. Bergen?"

"Nine at the moment," said Bergen. "All wives. We look forward to a time when we can have the normal ratio of one to one, but we still need workers and researchers primarily, and unless women have important qualifications of some sort-"

"They all have important qualifications of some sort, dear," said Mrs. Bergen. "You could keep the men for longer duty if-"

"My wife," said Bergen, laughing, "is a convinced feminist but is not above using sex as an excuse to enforce equality. I keep telling her that that is the feminine way of doing it and not the feminist way, and she keeps saying-Well, that's why she's pregnant. You think it's love, sex mania, yearning for motherhood? Nothing of the sort. She's going to have a baby down here to make a philosophical point."

Annette said coolly, "Why not? Either this is going to be home for humanity or it isn't going to be. If it is, then we're going to have babies here, that's all. I want a baby born in Ocean-Deep. There are babies born in Luna City, aren't there, Mr. Demerest?"

Demerest took a deep breath. "I was born in Luna City, Mrs. Bergen."

"And well she knew it, " muttered Bergen.

"And you are in your late twenties, I think?" she said.

"I am twenty-nine," said Demerest.

"And well she knew that, too," said Bergen with a short laugh. "You can bet she looked up all possible data on you when she heard you were coming."

"That is quite beside the point," said Annette. "The point is that for twenty-nine years at least children have been born in Luna City and no children have been born in Ocean-Deep."

"Luna City, my dear," said Bergen, "is longer-established. It is over half a century old; we are not yet twenty."

"Twenty years is quite enough. It takes a baby nine months."

Demerest interposed, "Are there any children in Ocean-Deep?"

"No," said Bergen. "No. Someday, though."

"In two months, anyway," said Annette Bergen positively.

The tension grew inside Demerest and when they returned to the unit in which he had first met Bergen, he was glad to sit down and accept a cup of coffee.

"We'll eat soon," said Bergen matter-of-factly. "I hope you don't mind sitting here meanwhile. As the prime unit, it isn't used for much except, of course, for the reception of vessels, an item I don't expect will interrupt us for a while. We can talk, if you wish."

"I do wish," said Demerest.

"I hope I'm welcome to join in," said Annette.

Demerest looked at her doubtfully, but Bergen said to him, "You'll have to agree. She's fascinated by you and by Moon-men generally. She thinks they're-uh-you're a new breed, and I think that when she's quite through being a Deep-woman she wants to be a Moon-woman:'

"I just want to get a word in edgewise, John, and when I get that in, I'd like to hear what Mr. Demerest has to say. What do you think of us, Mr. Demerest?"

Demerest said cautiously, "I've asked to come here, Mrs. Bergen, because I'm a safety engineer. Ocean-Deep has an enviable safety record-"

"Not one fatality in almost twenty years," said Bergen cheerfully. "Only one death by accident in the C-shelf settlements and none in transit by either sub or 'scaphe. I wish I could say, though, that this was the result of wisdom and care on our part. We do our best, of course, but the breaks have been with us-"

"John," said Annette, "I really wish you'd let Mr. Demerest speak."

"As a safety engineer," said Demerest, "I can't afford to believe in luck and breaks. We cannot stop Moon-quakes or large meteroites out at Luna City, but we are designed to minimize the effects even of those. There are no excuses or there should be none for human failure. We have not avoided that on Luna City; our record recently has been"-his voice dropped-"bad. While humans are imperfect, as we all know, machinery should be designed to take that imperfection into account. We lost twenty men and women-"

"I know. Still, Luna City has a population of nearly one thousand, doesn't it? Your survival isn't in danger."

"The people on Luna City number nine hundred and seventy-two, including myself, but our survival is in danger. We depend on Earth for essentials. That need not always be so; it wouldn't be so right now if the Planetary Project Council could resist the temptation toward pygmy economies-"

"There, at least, Mr. Demerest," said Bergen, "we see eye to eye. We are not self-supporting either, and we could be. What's more, we can't grow much beyond our present level unless nuclear 'scaphes are built. As long as we keep that buoyancy principle, we are limited. Transportation between Deep and Top is slow; slow for men; slower still for materiel and supplies. I've been pushing, Mr. Demerest, for-"

"Yes, and you'll be getting it now, Mr. Bergen, won't you?"

"I hope so, but what makes you so sure?"

"Mr. Bergen, let's not play around. You know very well that Earth is committed to spending a fixed amount of money on expansion projects-on programs designed to expand the human habitat-and that it is not a terribly large amount. Earth's population is not going to lavish resources in an effort to expand either outer space or inner space if it thinks this will cut into the comfort and convenience of Earth's prime habitat, the land surface of the planet." Annette broke in. "You make it sound callous of Earthmen, Mr. Demerest, and that's unfair.. It's only human, isn't it, to want to be secure? Earth is overpopulated and it is only slowly reversing the havoc inflicted on the planet by the Mad Twentieth. Surely man's original home must come first, ahead of either Luna City or Ocean-Deep. Heavens, Ocean-Deep is almost home to me, but I can't want to see it flourish at the expense of Earth's land."

"It's not an either-or, Mrs. Bergen," said Demerest earnestly. "If the ocean and outer space are firmly, honestly, and intelligently exploited, it can only redound to Earth's benefit. A small investment will be lost but a large one will redeem itself with profit."

Bergen held up his hand. "Yes, I know. You don't have to argue with me on that point. You'd be trying to convert the converted. Come, let's eat. I tell you what. We'll eat here. If you'll stay with us overnight, or several days for that matter-you're quite welcome-there will be ample time to meet everybody. Perhaps you'd rather take it easy for a while, though."

"Much rather," said Demerest. "Actually, I want to stay here...I would like to ask, by the way, why I met so few people when we went through the units."

"No mystery," said Bergen genially. "At any given time, some fifteen of our men are asleep and perhaps fifteen more are watching films or playing chess or, if their wives are with them-"

"Yes, John," said Annette.

"-And it's customary not to disturb them. The quarters are constricted and what privacy a man can have is cherished. A few are out at sea; three right now, I think. That leaves a dozen or so at work in here and you met them."

"I'll get lunch," said Annette, rising.

She smiled and stepped through the door, which closed automatically behind her.

Bergen looked after her. "That's a concession. She's playing woman for your sake. Ordinarily, it would be just as likely for me to get the lunch. The choice is not defined by sex but by the striking of random lightning."

Demerest said, "The doors between units, it seems to me, are of dangerously limited strength."

"Are they?"

"If an accident happened, and one unit was punctured-"

"No meteorites down here," said Bergen, smiling.

"Oh yes, wrong word. If there were a leak of any sort, for any reason, then could a unit or a group of units be sealed off against the full pressure of the ocean?"

"You mean, in the way that Luna City can have its component units automatically sealed off in case of meteorite puncture in order to limit damage to a single unit."

"Yes," said Demerest with a faint bitterness. "As did not happen recently."

"In theory, we could do that, but the chances of accident are much less down here. As I said, there are no meteorites and, what's more, there are no currents to speak of. Even an earthquake centered immediately below us would not be damaging since we make no fixed or solid contact with the ground beneath and are cushioned by the ocean itself against the shocks. So we can afford to gamble on no massive influx."

"Yet if one happened?"

"Then we could be helpless. You see, it is not so easy to seal off component units here. On the Moon, there is a pressure differentia] of just one atmosphere; one atmosphere inside and the zero atmosphere of vacuum outside. A thin seal is enough. Here at Ocean-Deep the pressure differential is roughly a thousand atmospheres. To secure absolute safety against that differentia] would take a great deal of money and you know what you said about getting money out of PPC. So we gamble and so far we've been lucky."

"And we haven't," said Demerest.

Bergen looked uncomfortable, but Annette distracted both by coming in with lunch at this moment.

She said, "I hope, Mr. Demerest, that you're prepared for Spartan fare. All our food in Ocean-Deep is prepackaged and requires only heating. We specialize in blandness and nonsurprise here, and the non-surprise of the day is a bland chicken a la king, with carrots, boiled potatoes, a piece of something that looks like a brownie for dessert, and, of course, all the coffee you can drink. "

Demerest rose to take his tray and tried to smile. "It sounds very like Moon fare, Mrs. Bergen, and I was brought up on that. We grow our own micro-organismic food. It is patriotic to eat that but not particularly enjoyable. We hope to keep improving it, though."

"I'm sure you will improve it...

Demerest said, as he ate with a slow and methodical chewing, "I hate to ride my specialty, but how secure are you against mishaps in your air-lock entry?"

"It is the weakest point of Ocean-Deep," said Bergen. He had finished eating, well ahead of the other two, and was half through with his first cup of coffee. "But there's got to be an interface, right? The entry is as automatic as we can make it and as fail-safe. Number one: there has to be contact at every point about the outer lock before the fusion generator begins to heat the water within the lock. What's more, the contact has to be metallic and of a metal with just the magnetic permeability we use on our 'scaphes. Presumably a rock or some mythical deep-sea monster might drop down and make contact at just the right places; but if so, nothing happens.

"Then, too, the outer door doesn't open until the steam has pushed the water out and then condensed; in other words, not till both pressure and temperature have dropped below a certain point. At the moment the outer door begins to open, a relatively slight increase in internal pressure, as by water entry, will close it again."

Demerest said, "But then, once men have passed through the lock, the inner door closes behind them and sea water must be allowed into the lock again. Can you do that gradually against the full pressure of the ocean outside?"

"Not very." Bergen smiled. "It doesn't pay to fight the ocean too hard. You have to roll with the punch. We slow it down to about one-tenth free entry but even so it comes in like a rifle shot-louder, a thunderclap, or waterclap, if you prefer. The inner door can hold it, though, and it is not subjected to the strain very often. Well, wait, you heard the waterclap when we first met, when Javan's 'scaphe took off again. Remember?"

"I remember," said Demerest. "But here is something I don't understand. You keep the lock filled with ocean at high pressure at all times to keep the outer door without strain. But that keeps the inner door at full strain. Somewhere there has to be strain."

"Yes, indeed. But if the outer door, with a thousand-atmosphere differential on its two sides, breaks down, the full ocean in all its millions of cubic miles tries to enter and that would be the end of all. If the inner door is the one under strain and it gives, then it will be messy indeed, but the only water that enters Ocean-Deep will be the very limited quantity in the lock and its pressure will drop at once. We will have plenty of time for repair, for the outer door will certainly hold a long time."

"But if both go simultaneously-"

"Then we are through." Bergen shrugged. "I need not tell you that neither absolute certainty nor absolute safety exists. You have to live with some risk and the chance of double and simultaneous failure is so microscopically small that it can be lived with easily."

"If all your mechanical contrivances fail-"

"They fail safe," said Bergen stubbornly.

Demerest nodded. He finished the last of his chicken. Mrs. Bergen was already beginning to clean up. "You'll pardon my questions, Mr. Bergen, I hope."

"You're welcome to ask. I wasn't informed, actually, as to the precise nature of your mission here. 'Fact finding' is a weasel phrase. However, I assume there is keen distress on the Moon over the recent disaster and as safety engineer you rightly feel the responsibility of correcting whatever shortcomings exist and would be interested in learning, if possible, from the system used in Ocean-Deep."

"Exactly. But, see here, if all your automatic contrivances fail safe for some reason, for any reason, you would be alive, but all your escape-hatch mechanisms would be sealed permanently shut. You would be trapped inside Ocean-Deep and would exchange a slow death for a fast one."

"It's not likely to happen but we'd hope we could make repairs before our air supply gave out. Besides we do have a manual backup system."

"Oh?"

"Certainly. When Ocean-Deep was first established and this was the only unit-the one we're sitting in now-manual controls were all we had. That was unsafe, if you like. There they are, right behind you-covered with friable plastic."

"In emergency, break glass," muttered Demerest, inspecting the covered setup.

"Pardon me?"

"Just a phrase commonly used in ancient fire-fighting systems...Well, do the manuals still work, or has the system been covered with your friable plastic for twenty years to the point where it has all decayed into uselessness with no one noticing?"

"Not at all. It's periodically checked, as all our equipment is. That's not my job personally, but I know it is done. If any electrical or electronic circuit is out of its normal working condition, lights flash, signals sound, everything happens but a nuclear blast.,..You know, Mr. Demerest, we are as curious about Luna City as you are about Ocean-Deep. I presume you would be willing to invite one of our young men-"

"How about a young woman?" interposed Annette at once.

"I am sure you mean yourself, dear," said Bergen, "to which

I can only answer that you are determined to have a baby here and to keep it here for a period of time after birth, and that effectively eliminates you from consideration."

Demerest said stiffly, "We hope you will send men to Luna City. We are anxious to have you understand our problems."

"Yes, a mutual exchange of problems and of weeping on each other's shoulders might be of great comfort to all. For instance, you have one advantage on Luna City that I wish we could have. With low gravity and a low pressure differential, you can make your caverns take on any irregular and angular fashion that appeals to your aesthetic sense or is required for convenience. Down here we're restricted to the sphere, at least for the foreseeable future, and our designers develop a hatred for the spherical that surpasses belief. Actually it isn't funny. It breaks them down. They eventually resign rather than continue to work spherically."

Bergen shook his head and leaned his chair back against a microfilm cabinet. "You know," he continued, "when William Beebe built the first deep-set chamber in history in the 1930s-it was just a gondola suspended from a mother ship by a half-mile cable, with no buoyancy chambers and no engines, and if the cable broke, good night, only it never did...Anyway, what was I saying? Oh, when Beebe built his first deep-sea chamber, he was going to make it cylindrical; you know, so a man would fit in it comfortably. After all, a man is essentially a tall, skinny cylinder. However, a friend of his argued him out of that and into a sphere on the very sensible grounds that a sphere would resist pressure more efficiently than any other possible shape. You know who that friend was?"

"No, I'm afraid I don't."

"The man who was President of the United States at the time of Beebe's descents-Franklin D. Roosevelt. All these spheres you see down here are the great-grandchildren of Roosevelt's suggestion."

Demerest considered that briefly but made no comment. He returned to the earlier topic. "We would particularly like someone from Ocean-Deep," he said, "to visit Luna City because it might lead to a great enough understanding of the need, on Ocean-Deep's part, for a course of action that might involve considerable self-sacrifice."

"Oh?" Bergen's chair came down flat-leggedly on all fours. "How's that?"

"Ocean-Deep is a marvelous achievement; I wish to detract nothing from that. I can see where it will become greater still, a wonder of the world. Still-"

"Still?"

"Still, the oceans are only a part of the Earth; a major part, but only a part. The deep sea is only part of the ocean. It is inner space indeed; it works inward, narrowing constantly to a point."

"I think," broke in Annette, looking rather grim, "that you're about to make a comparison with Luna City."

"Indeed I am," said Demerest. "Luna City represents outer space, widening to infinity. There is nowhere to go down here in the long run; everywhere to go out there."

"We don't judge by size and volume alone, Mr. Demerest," said Bergen. "The ocean is only a small part of Earth, true, but for that very reason it is intimately connected with over five billion human beings. Ocean-Deep is experimental but the settlements on the continental shelf already deserve the name of cities. Ocean-Deep offers mankind the chance of exploiting the whole planet-"

"Of polluting the whole planet," broke in Demerest excitedly. "Of raping it, of ending it. The concentration of human effort to Earth itself is unhealthy and even fatal if it isn't balanced by a turning outward to the frontier."

"There is nothing at the frontier," said Annette, snapping out the words. "The Moon is dead, all the other worlds out there are dead. If there are live worlds among the stars, light-years away, they can't be reached. This ocean is living."

"The Moon is living, too, Mrs. Bergen, and if Ocean-Deep allows it, the Moon will become an independent world. We Moon-men will then see to it that other worlds are reached and made alive and, if mankind but has patience, we will reach the stars. We! We! It is only we Moon-men, used to space, used to a world in a cavern, used to an engineered environment, who could endure life in a spaceship that may have to travel centuries to reach the stars."

"Wait, wait, Demerest," said Bergen, holding up his hand. "Back up! What do you mean, if Ocean-Deep allows it? What have we to do with it?"

"You're competing with us, Mr. Bergen. The Planetary Project Commission will swing your way, give you more, give us less, because in the short term, as your wife says, the ocean is alive and the Moon, except for a thousand men, is not; because you are a half-dozen miles away and we a quarter of a million; because you can be reached in an hour and we only in three days. And because you have an ideal safety record and we have had-misfortunes."

"The last, surely, is trivial. Accidents can happen any time, anywhere."

"But the trivial can be used," said Demerest angrily. "It can be made to manipulate emotions. To people who don't see the purpose and the importance of space exploration, the death of Moon-men in,accidents is proof enough that the Moon is dangerous, that its colonization is a useless fantasy. Why not? It's their excuse for saving money and they can then salve their consciences by investing part of it in Ocean-Deep instead. That's why I said the accident on the Moon had threatened the survival of Luna City even though it killed only twenty people out of nearly a thousand."

"I don't accept your argument. There has been enough money for both for a score of years."

"Not enough money. That's exactly it. Not enough investment to make the Moon self-supporting in all these years, and then they use that lack of self-support against us. Not enough investment to make Ocean-Deep self-supporting either... But now they can give you enough if they cut us out altogether."

"Do you think that will happen?"

"I'm almost sure it will, unless Ocean-Deep shows a statesmanlike concern for man's future."

"How?"

"By refusing to accept additional funds. By not competing with Luna City. By putting the good of the whole race ahead of self-interest."

"Surely you don't expect us to dismantle-"

"You won't have to. Don't you see? Join us in explaining that Luna City is essential, that space exploration is the hope of mankind; that you will wait, retrench, if necessary."

Bergen looked at his wife and raised his eyebrows. She shook her head angrily. Bergen said, "You have a rather romantic view of the PPC, I think. Even if I made noble, self-sacrificing speeches, who's to say they would listen? There's a great deal more involved in the matter of Ocean-Deep than my opinion and my statements. There are economic considerations and public feeling. Why don't you relax, Mr. Demerest? Luna City won't come to an end. You'll receive funds, I'm sure of it. I tell you, I'm sure of it. Now let's break this up"

"No, I've got to convince you one way or another that I'm serious. If necessary, Ocean-Deep must come to a halt unless the PPC can supply ample funds for both."

Bergen said, "Is this some sort of official mission, Mr. Demerest? Are you speaking for Luna City officially, or just for yourself?"

"Just for myself, but maybe that's enough, Mr. Bergen."

"I don't think it is. I'm sorry, but this is turning out to be unpleasant. I suggest that, after all, you had better return Topside on the first available 'scaphe."

"Not yet! Not yet!" Demerest looked about wildly, then rose unsteadily and put his back against the wall. He was a little too tall for the room and he became conscious of life receding. One more step and he would have gone too far to back out.

He had told them back on the Moon that there would be no use talking, no use negotiating. It was dog-eat-dog for the available funds and Luna City's destiny must not be aborted; not for Ocean-Deep; not -for Earth; no, not for all of Earth, since mankind and the Universe came even before the Earth. Man must outgrow his womb and

Demerest could hear his own ragged breathing and the inner turmoil of his whirling thoughts. The other two were looking at him with what seemed concern. Annette rose and said, "Are you ill, Mr. Demerest?"

"I am not ill. Sit down. I'm a safety engineer and I want to teach you about safety. Sit down, Mrs. Bergen."

"Sit down, Annette," said Bergen. "I'll take care of him." He rose and took a step forward.

But Demerest said, "No. Don't you move either. I have something right here. You're too naive concerning human dangers, Mr. Bergen. You guard against the sea and against mechanical failure and you don't search your human visitors, do you? I have a weapon, Bergen."

Now that it was out and he had taken the final step, from which there was no returning, for he was now dead whatever he did, he was quite calm.

Annette said, "Oh, John," and grasped her husband's arm. "He's-"

Bergen stepped in front of her. "A weapon? Is that what that thing is? Now slowly, Demerest, slowly. There's nothing to get hot over. If you want to talk, we will talk. What is that?"

"Nothing dramatic. A portable laser beam."

"But what do you want to do with it?"

"Destroy Ocean-Deep."

"But you can't, Demerest. You know you can't. There's only so much energy you can pack into your fist and any laser you can hold can't pump enough heat to penetrate the walls."

"I know that. This packs more energy than you think. It's Moon-made and there are some advantages to manufacturing the energy unit in a vacuum. But you're right. Even so, it's designed only for small jobs and requires frequent recharging. So I don't intend to try to cut through a foot-plus of alloy steel...But it will do the job indirectly. For one thing, it will keep you two quiet. There's enough energy in my fist to kill two people."

"You wouldn't kill us," said Bergen evenly. "You have no reason."

"If by that," said Demerest, "you imply that I am an unreasoning being to be somehow made to understand my madness, forget it. I have every reason to kill you and I will kill you. By laser beam if I have to, though I would rather not.".

"What good will killing us do you? Make me understand. Is it that I have refused to sacrifice Ocean-Deep funds? I couldn't do anything else. I'm not really the one to make the decision. And if you kill me, that won't help you force the decision in your direction, will it? In fact, quite the contrary. If a Moon-man is a murderer, how will that reflect on Luna City? Consider human emotions on Earth."

There was just an edge of shrillness in Annette's voice as she joined in. "Don't you see there will be people who will say that Solar radiation on the Moon has dangerous effects? That the genetic engineering which has reorganized your bones and muscles has affected mental stability? Consider the word 'lunatic,' Mr. Demerest. Men once believed the Moon brought madness."

"I am not mad, Mrs. Bergen."

"It doesn't matter," said Bergen, following his wife's lead smoothly. "Men will say that you were; that all Moon-men are; and Luna City will be closed down and the Moon itself closed to all further exploration, perhaps forever. Is that what you want?"

"That might happen if they thought I killed you, but they won't. It will be an accident." With his left elbow, Demerest broke the plastic that covered the manual controls.

"I know units of this sort," he said. "I know exactly how it works. Logically, breaking that plastic should set up a warning flash-after all, it might be broken by accident-and then someone would be here to investigate, or, better yet, the controls should lock until deliberately released to make sure the break w~ not merely accidental."

He paused, then said, "But I'm sure no one will come; that no warning has taken place. Your manual system is not failsafe because in your heart you were sure it would never be used."

"What do you plan to do?" said Bergen.

He was tense and Demerest watched his knees carefully, and said, "If you try to jump toward me, I'll shoot at once, and then keep right on with what I'm doing."

"I think maybe you're giving me nothing to lose."

"You'll lose time. Let me go right on without interference and you'll have some minutes to keep on talking. You may even be able to talk me out of it. There's my proposal. Don't interfere with me and I will give you your chance to argue."

"But what do you plan to do?"

"This," said Demerest. He did not have to look. His left hand snaked out and closed a contact. "The fusion unit will now pump heat into the air lock and the steam will empty it. It will take a few minutes. When it's done, I'm sure one of those little red-glass buttons will light."

"Are you going to-"

Demerest said, "Why do you ask? You know that I must be intending, having gone this far, to Rood Ocean-Deep?"

"But why? Damn it, why?"

"Because it will be marked down as an accident. Because your safety record will be spoiled. Because it will be a complete catastrophe and will wipe you out. And PPC will then turn from you, and the glamor of Ocean-Deep will be gone. We will get the funds; we will continue. If I could bring that to pass in some other way, I would, but the needs of Luna City are the needs of mankind and those are paramount."

"You will die, too," Annette managed to say.

"Of course. Once I am forced to do something like this, would I want to live? I'm not a murderer."

"But you will be. If you flood this unit, you will flood all of Ocean-Deep and kill everyone in it-and doom those who are out in their subs to slower death. Fifty men and women -an unborn child-"

"That is not my fault," said Demerest, in clear pain. "I did not expect to find a pregnant woman here, but now that I have, I can't stop because of that."

"But you must stop," said Bergen. "Your plan won't work unless what happens can be shown to be an accident. They'll find you with a beam emitter in your hand and with the manual controls clearly tampered with. Do you think they won't deduce the truth from that?"

Demerest was feeling very tired. "Mr. Bergen, you sound desperate. Listen-When the outer door opens, water under a thousand atmospheres of pressure will enter. It will be a massive battering ram that will destroy and mangle everything in its path. The walls of the Ocean-Deep units will remain but everything inside will be twisted beyond recognition. Human beings will be mangled into shredded tissue and splintered bone and death will be instantaneous and unfelt. Even if I were to burn you to death with the laser there would be nothing left to show it had been done, so I won't hesitate, you see. This manual unit will be smashed anyway; anything I can do will be erased by the water."

"But the beam emitter, the laser gun. Even damaged, it will be recognizable," said Annette.

"We use such things on the Moon, Mrs. Bergen. It is a common tool; it is the optical analogue of a jackknife. I could kill you with a jackknife, you know, but one would not deduce that a man carrying a jackknife, or even holding one with the blade open, was necessarily planning murder. He might be whittling. Besides, a Moon-made laser is not a projectile gun. It doesn't have to withstand.an internal explosion. It is made of thin metal, mechanically weak. After it is smashed by the waterclap I doubt that it will make much sense as an object."

Demerest did not have to think to make these statements. He had worked them out within himself through months of self-debate back on the Moon.

"In fact," he went on, "how will the investigators ever know what happened in here? They will send 'scaphes down to inspect what is left of Ocean-Deep, but how can they get inside without first pumping the water out? They will, in effect, have to build a new Ocean-Deep and that would take-how long? Perhaps, given public reluctance to waste money, they might never do it at all and content themselves with dropping a laurel wreath on the dead walls of the dead Ocean-Deep."

Bergen said, "The men on Luna City will know what you have done. Surely one of them will have a conscience. The truth will be known."

"One truth," said Demerest, "is that I am not a fool. No one on Luna City knows what I planned to do or will suspect what I have done. They sent me down here to negotiate cooperation on the matter of financial grants. I was to argue and nothing more. There's not even a laser-beam emitter missing up there. I put this one together myself out of scrapped parts...And it works. I've tested it."

Annette said slowly, "You haven't thought it through. Do you know what you're doing?"

"I've thought it through. I know what I'm doing...And I know also that you are both conscious of the lit signal. I'm aware of it. The air lock is empty and time's up, I'm afraid."

Rapidly, holding his beam emitter tensely high, he closed another contact. A circular part of the unit wall cracked into a thin crescent and rolled smoothly away.

Out of the corner of his eye, Demerest saw the gaping darkness, but he did not look. A dankly salt vapor issued from it; a queer odor of dead steam. He even imagined he could: hear the flopping sound of the gathered water at the bottom of the lock.

Demerest said, "In a rational manual unit, the outer door ought to be frozen shut now. With the inner door open, nothing ought to make the outer door open. I suspect, though, that the manuals were put together too quickly at first for that precaution to have been taken, and it was replaced too quickly for that precaution to have been added. And if I need further evidence of that, you wouldn't be sitting there so tensely if you knew the outer door wouldn't open. I need touch one more contact and the waterclap will come. We will feel nothing. "

Annette said, "Don't push it just yet. I have one more thing to say. You said we would have time to persuade you."

"While the water was being pushed out."

"Just let me say this. A minute. A minute. I said you didn't know what you were doing. You don't. You're destroying the space program, the space program. There's more to space than space." Her voice had grown shrill.

Demerest frowned. "What are you talking about? Make sense, or I'll end it all. I'm tired. I'm frightened. I want it over."

Annette said, "You're not in the inner councils of the PPC. Neither is my husband. But I am. Do you think because I am a woman that I'm secondary here? I'm not. You, Mr. Demerest, have your eyes fixed on Luna City only. My husband has his fixed on Ocean-Deep. Neither of you know anything.

"Where do you expect to go, Mr. Demerest, if you had all the money you wanted? Mars? The asteroids? The satellites of the gas giants? These are all small worlds; all dry surfaces under a blank sky. It may be generations before we are ready to try for the stars and till then we'd have only pygmy real estate. Is that your ambition?

"My husband's ambition is no better. He dreams of pushing man's habitat over the ocean Boor, a surface not much larger in the last analysis than the surface of the Moon and the other pygmy worlds. We of the PPC, on the other hand, want more than either of you, and if you push that button, Mr. Demerest, the greatest dream mankind has ever had will come to nothing."

Demerest found himself interested despite himself, but he said, "You're just babbling." It was possible, he knew, that somehow they had warned others in Ocean-Deep, that any moment someone would come to interrupt, someone would try to shoot him down. He was, however, staring at the only opening, and he had only to close one contact, without even looking, in a second's movement.

Annette said, "I'm not babbling. You know it took more than rocket ships to colonize the Moon. To make a successful colony possible, men had.to be altered genetically and adjusted to low gravity. You are a product of such genetic engineering."

"Well?"

"And might not genetic engineering also help men to greater gravitational pull? What is the largest planet of the Solar System, Mr. Demerest?"

"Jupi-"

"Yes, Jupiter. Eleven times the diameter of the Earth; forty times the diameter of the Moon. A surface a hundred and twenty times that of the Earth in area; sixteen hundred times that of the Moon. Conditions so different from anything we can encounter anywhere on the worlds the size of Earth or less that any scientist of any persuasion would give half his life for a chance to observe at close range."

"But Jupiter is an impossible target."

"Indeed?" said Annette, and even managed a faint smile. "As impossible as flying? Why is it impossible? Genetic engineering could design men with stronger and denser bones, stronger and more compact muscles. The same principles that enclose Luna City against the vacuum and Ocean-Deep against the sea can also enclose the future Jupiter-Deep against its ammoniated surroundings."

"The gravitational field-"

"Can be negotiated by nuclear-powered ships that are now on the drawing board. You don't know that but I do."

"We're not even sure about the depth of the atmosphere. The pressures-"

"The pressures! The pressures! Mr. Demerest, look about you. Why do you suppose Ocean-Deep was really built? To exploit the ocean? The settlements on the continental shelf are doing that quite adequately. To gain knowledge of the deep-sea bottom? We could do that by 'scaphe easily and we could then have spared the hundred billion dollars invested in Ocean-Deep so far.

"Don't you see, Mr. Demerest, that Ocean-Deep must mean something more than that? The purpose' of Ocean-Deep is to devise the ultimate vessels and mechanisms that will suffice to explore and colonize Jupiter. Look about you and see the beginnings of a Jovian environment; the closest approach we can come to it on Earth. It is only a faint image of mighty Jupiter, but it's a beginning.

"Destroy this, Mr. Demerest, and you destroy any hope for Jupiter. On the other hand, let us live and we will, together, penetrate and settle the brightest jewel of the Solar System. And long before we can reach the limits of Jupiter, we will be ready for the stars, for the Earth-type planets circling them, and the Jupiter-type planets, too. Luna City won't be abandoned because both are necessary for this ultimate aim."

For the moment, Demerest had altogether forgotten about that last button. He said, "Nobody on Luna City has heard of this."

"You haven't. There are those on Luna City who know. If you had told them of your plan of destruction, they would have stopped you. Naturally, we can't make this common knowledge and only a few people anywhere can know. The public supports only with difficulty the planetary projects now in progress. If the PPC is parsimonious it is because public opinion limits its generosity. What do you suppose public opinion would say if they thought we were aiming toward Jupiter? What a super-boondoggle that would be in their eyes. But we continue and what money we can save and make use of we place in the various facets of Project Big World."

"Project Big World?"

"Yes," said Annette. "You know now and I have committed a serious security breach. But it doesn't matter, does it? Since we're all dead and since the project is, too."

"Wait. now, Mrs. Bergeh."

"If you change your mind now, don't think you can ever talk about Project Big World. That would end the project just as effectively as destruction here would. And it would end both your career and mine. It might end Luna City and Ocean-Deep, too-so now that you know, maybe it makes no difference anyway. You might just as well push that button."

"I said wait-" Demerest's brow was furrowed and his eyes burned with anguish. "I don't know-"

Bergen gathered for the sudden jump as Demerest's tense alertness wavered into uncertain introspection, but Annette grasped her husband's sleeve.

A timeless interval that might have been ten seconds long followed and then Demerest held out his laser. "Take it," he said. "I'll consider myself under arrest."

"You can't be arrested," said Annette, "without the whole story coming out." She took the laser and gave it to Bergen. "It will be enough that you return to Luna City and keep silent. Till then we will keep you.under guard."

Bergen was at the manual controls. The inner door slid shut and after that there was the thunderous waterclap of the water returning into the lock.

Husband and wife were alone again. They had not dared say a word until Demerest was safely put to sleep under the watchful eyes of two men detailed for the purpose. The unexpected waterclap had roused everybody and a sharply bowdlerized account of the incident had been given out.

The manual controls were now locked off and Bergen said, "From this point on, the manuals:will have to be adjusted to fail-safe. And visitors will have to be searched."

"Oh, John," said Annette. "I think people are insane. There we were, facing death for us and for Ocean-Deep; just the end of everything. And I kept thinking-1 must keep calm; I mustn't have a miscarriage."

"You kept calm all right. You were magnificent. I mean, Project Big World! I never conceived of such a thing, but by -by-Jove, it's an attractive thought. It's wonderful."

"I'm sorry I had to say all that, John. It was all a fake, of course. I made it up, Demerest wanted me to make something up really. He wasn't a killer or destroyer; he was, according to his own overheated lights, a patriot, and I suppose he was telling himself he must destroy in order to save -a common enough view among the small-minded. But he said he would give us time to talk him out of it and I think he was praying we would manage to do so. He wanted us to think of something that would give him the excuse to save in order to save, and I gave it to him. I'm sorry I had to fool you, John."

"You didn't fool me."

"I didn't?"

"How could you? I knew you weren't a member of PPC."

"What made you so sure of that? Because I'm a woman?"

"Not at all. Because I'm a member, Annette, and that's confidential. And, if you don't mind, I will begin a move to initiate exactly what you suggested-Project Big World."

"Well!" Annette considered that and, slowly, smiled. "Well! That's not bad. Women do have their uses."

"Something," said Bergen, smiling also, "I have never denied."

Ed Ferman of F amp; SF and Barry Malzberg, one of the brightest of the new generation of science fiction writers, had it in mind in early 1973 to prepare an anthology in which a number of different science fiction themes were carried to their ultimate conclusion. For each story they tapped some writer who was associated with a particular theme, and for a story on the subject of robotics, they wanted me, naturally.

I tried to beg off with my usual excuses concerning the state of my schedule, but they said if I didn't do it there would be no story on robotics at all, because they wouldn't ask anyone else. That shamed me into agreeing to do it.

I then had to think up a way of reaching an ultimate conclusion. There had always been one aspect of the robot theme I had never had the courage to write, although the late John Campbell and I had sometimes discussed it.

In the first two Laws of Robotics, you see, the expression "human being" is used, and the assumption is that a robot can recognize a human being when he sees one. But what is a human being? Or, as the Psalmist asks of God, "What is man that thou art mindful of him?"

Surely, if there's any doubt as to the definition of man, the Laws of Robotics don't necessarily hold. So I wrote THAT THOU ART MINDFUL OF HIM, and Ed and Barry were very happy with it-and so was I. It not only appeared in the anthology, which was entitled Final Stage, but was also published in the May 1974 issue of F amp; SF.