The Nitrogen Fix

by Hal Clement

  “You must know,” she said at last, “what sort of life form does oxidize the nitrogen. Is it a pseudolife of the sort people made, or nitro-life like yours which is most of what grows now?”

  ‘It is nitro-life,” the Observer replied. “There are a large number of species. However, much of the pseudolife you use is of the same variety. It would seem possible that artificial life made by your people was indeed responsible for the change.”

  “But pseudolife is so stable, and nitro-life mutates so easily.

  “Which is why a single mistake on the part of your life technicians could have sufficed.”

  “I’d hate to have Genda turn out to be right. She’s bad enough to listen to now,” Kahvi muttered.

  Bones did not understand this in the least, and waited for something answerable. It came.

  “You know how pseudolife is made — you could make it yourself.”

  “Yes.”

  “Could you make any of the kinds which oxidize nitrogen?”

  “Yes.”

  “Would it be more difficult than making other kinds, or might it happen by accident?”

  “It could hardly happen by accident. All the organisms able to do this, on every world I remember, use one or another of four enzymes — you know what they are?”

  “Of course. The symbol is plain enough; we’ve talked about such things in our own life systems.”

  “Those enzymes use a very surprising metal.”

  “What’s surprising about it?”

  “We have not been able to learn why it is so widespread in every planet’s crust. It is one of the standing mysteries, which presents itself on world after world. It is a highly unreactive metal, which I would expect to find uncombined and highly localized. It should not be so thoroughly spread through a planet’s soil and crust that a microbe can count on finding enough of its atoms whenever it needs them for its personal chemistry. One hypothesis is that a scientific race used and scattered it, but there has been no way to tell; I have never found a use for it myself, except in the most limited quantities in the laboratory.

  That is one reason I want to talk to these people of yours who seem to be somewhat scientific in nature.

  They might have knowledge of their own, even if memories are gone.”

  Kahvi had her doubts about this; she felt that she knew pretty accurately the scientific status of the Delinquents. Essentially, they had probably been playing with cultures and Evolution Plant enzymes on ahit-or-miss basis. However, that was Bones problem.

  “What is this metal?” she asked. “Some obscure heavy element they never mentioned either in Surplus School or Citizen s Training, I suppose.”

  “You know about it,” Bones replied. A handling tentacle reached out and touched the gold bracelet on her left wrist.

  XX

  Answers, Applied

  If one of the Delinquents, or even an ordinary Hiller, had said it, Kahvi might have doubted; but Bones was Bones. Nomads merely regarded lying as hopelessly immoral; Bones didn’t know what it was, since it was impossible in her natural method of communication. A human being might have been honestly wrong; Bones knew.

  There had been an Earth with a breathable atmosphere. And millions and millions of people. A slow grin spread over Kahvi’s face. Her lip trembled, and she suddenly burst into laughter; peal after peal of uncontrollable laughter. Bones was familiar with this manifestation of the human nervous system’s reaction to incongruity, but was mystified by the lack of any obvious incongruity this time. Kahvi, when she could finally stop, was little help.

  “I’d like to be translating, or at least standing there, when you tell that to Genda and Rembert’s crowd at the same time!” was all she said.

  “Why won’t you be?” was the natural question.

  “We can’t leave the kids out at Copper that long. I’d trust Danna, but the other two are older and will have to show her they’re smarter, sometime or other. We can hope they’re reasonably safe so far, but that won’t last more than a few hours if nothing happens to them.” She paused to think for a moment.

  “Here’s what we’ll do. I’ll go ashore and tell the Delinquents that you’ve come back and are willing to talk, and that you’ve put the kids ‘way out of their reach. I’ll tell them that you know just what happened to the world’s air — ”

  “But I don’t!” objected the Observer, startled.

  “But you certainly do. A hundred million-a billion-ten billion-whatever it was-people like me wearing gold ornaments. Jewelry. That’s what spread the metal over the world so well. It’s obvious. It wasn’t your doing, it wasn’t science’s doing. Can’t you just see Genda and those young devils having to admit to each other that they’re both wrong?” Neither Kahvi nor Bones had any grasp of the basic human skill at avoiding any such admission. “I’ll tell ‘em you know, and that you’ll explain to everyone who wants to listen at, say, sunrise tomorrow. That will give them plenty of time to fetch all the people they want, and give you plenty of time to get me out to Copper and come back again. When you do explain, they won’t have any more reason to kill you; it obviously doesn’t matter to you what the air is like, and they should be able to see that. That means you will have no reason for interfering in their attempt to change it back.

  Oh!”

  “What?”

  “One of them was saying-you were captured in Hemenway in a room with a lot of plants and things?”

  “Yes.”

  “You smashed some of the planters?”

  “I threw one at people who were throwing spears at me.”

  “Why did you pick that one?”

  “It was nearest.”

  “I hope you can convince them. I gather it was a culture of whatever they are planning to change the air back-something that will reduce nitrates very fast. I don’t know what it uses for energy. That fellow was sure you’d tried to destroy it on purpose.” She thought for some seconds. “I still can’t come up with anything better. Can you?”

  “No,” admitted Bones. “In any case, we should start your trip to Copper. I suggest you go to tellthose people what you can. I will make another boat, of the sort I carried the children on; it will save much time in the long run. I’ll be back with it shortly. If they’ll let you come with me, fine; if not, we’ll have to think of something else. If necessary, I will go back and bring the children here; they would be safer, I suppose, even with these other people around.”

  “I’m afraid so. We’ll try this, though.” Kahvi got dressed and slid through the hatchway. Bones followed, watched her for a moment as she stood up and began to wade toward the group on the shore, and then dolphined at top speed toward the north and the supply of Newell tissue.

  Half an hour later the slab of solid foam came bobbing back into view of the jail area. Kahvi, rather to Bones’ surprise, was waiting in waist-deep water; she clambered onto the crudely streamlined float, and the native promptly headed eastward again.

  She looked back several times, but had to give most of her attention to holding on; the board literally bounced from wave to wave at times. She wondered how the children had managed — surely Bones hadn’t travelled this fast with them! No worry; there had been no mention of losing any, and Bones had said that they — plura1, definitely — were safe at Copper.

  But there were worries at both ends of the trip. Had the youngsters done anything dangerous?

  She could trust her own daughter, but didn’t know the others very well. And what was happening to Earrin, in the hands of the Delinquents? She gave another look aft, and gasped.

  Smoke was rising from the jail area — it seemed to be the jail area — her eyes and her mask window wouldn’t let her be certain. It had to be smoke; the sky was cloudless, and it was rising visibly. What had happened? Was Earrin safe? She strained her eyes, but could make out nothing more, and was drawing away from the scene as the seconds passed. Should she go back? What would happen to the children if she did? Maybe Bones could see better,
and tell her what was going on.

  She jerked repeatedly on the tow harness, but the water was far too choppy to let the Observer tell one tug on the rope from another, and she was swimming entirely under water. The Canton shore and the smoke slowly faded astern, and finally disappeared around the Blue Hills peninsula. Kahvi settled for looking ahead.

  The children were safe. After a single glance had made this clear, Kahvi frantically passed the new information to the native. Bones was about to plunge back into the water to go back to Canton; she barely stopped the dive.

  “What do you want?” asked the Observer. “I can get back much more quickly alone, and bring I word back to you.”

  “But you wouldn’t know what has happened to Earrin! Those young monsters said they’d kill him if anything went wrong, and obviously something’s wrong! They might blame him, or me, for whatever made the smoke.”

  “Do you wish to come back and leave these young ones?”

  “Yes! — No-I don’t know-the children could still-”

  “Your husband can probably take care of himself without you better than they can.

  “I suppose he can-but I’m not-I don’t know-look,” Kahvi took command of herself with an effort, “I can ride this other boat you made. The kids can come with us. We can get back pretty quickly; it’s only a few kilos.”

  Bones thought of several objections, but curiosity about human psychology won out. Ten minutes later the woman, the three children, and a supply of cartridges and food pods were on the larger boat, and the group was moving as fast as the native could drag it back toward the west.

  Kahvi was explaining everything to the children, and all were looking eagerly or anxiously ahead for the moment when Canton would be visible around the big peninsula.

  When it was, the sight was not encouraging. The smoke was still rising. Danna whimpered in terror, and the older children were little better off, their own parents were there too. Kahvi would have liked to be encouraging, but there was nothing very helpful that her conscience would let her say. They could only watch and hope as the meters flowed backward and the scene grew clearer.

  It was obvious before they neared the raft that the new building was gone. Smoke was still funneling up from where it had been. The raft appeared intact, however, and it seemed unlikely that any of theprisoners would have been in the lab. Danna looked anxiously at the source of the smoke, but her mother was more interested in the crowd of people. This was far larger than it had been. When she had left, a scant hour before, the forty or fifty adolescents and their captives had been near the jail and along the shore. Now there were at least two hundred, she was sure, though they milled about to o much to make counting possible. Were there really this many rebels against common sense and order?

  No. She could see now that most of those in sight were barefoot, which was a very good sign. They must be conventional Hillers. What had brought them? And what had happened to the hostages? Kahvi strained to identify faces and forms as the boat drew near, but had not found any she wanted when the slab of foamy tissue slowed and bumped into the suddenly erect form of Bones, a few meters from the beach.

  The crowd had seen them coming, and most of its members had turned from the dying fire and spread along the water’s edge. Kahvi slowly got off the boat and stood hip-deep, still looking for her husband. He definitely wasn’t there. Convinced of this, she turned to Bones and signaled briefly, “The children will stay on the boat. Please keep them out of reach of these people until I say it’s all right.” She repeated the essence of these instructions aloud to the children themselves, and then rather hesitantly began to wade toward the crowd.

  Suddenly she saw Viah and Jonathan jostling their way from behind the others, and called to them.

  “Your boy is all right. So are the others. Where’s Earrin?” The two looked at each other, and Viah finally answered.

  “He’s hurt, I’m afraid. Some of the delinquents tried to spear him when the rest of the people showed up. They decided you had sneaked over the Hill and told about them. I think he’ll be all right, but he has some pretty bad cuts and lost a lot of blood.” Kahvi reached the shore as Viah finished speaking.

  “Where is he?”

  “In the jail. The air is still rather high — the young devils got the cartridge tissue out and the new spores aren’t anywhere near taking over. It seemed better to give him stronger air when he had so much blood gone.” Kahvi frowned, influenced for a moment by her normal prejudices, but said nothing. She had to grant the force of the reasoning.

  She started toward the stone building; people moved aside for her. Most of them were silent; most had never seen a Nomad. The more conventional and courteous ones could not quite decide what to say to such a stranger, especially a pregnant one. There was some murmuring behind masks among the more distant members of the group, but Kahvi couldn’t make out the words.

  “I take it the Delinquents are under control,” she said as Viah and her husband reached the lock with her.

  “Yes,” the man replied. “When we and Zhamia and Mort didn’t appear back at the city, of course a group went out to look for us. They saw the smoke from a distance, and immediately sent back for still more help-they weren’t close enough to tell whether it was a jail or something really general. When the big group got here, there really wasn’t much the D’s could do, though a couple of them thought they should keep their promise about killing hostages. I don’t know what they’ve been reading, but they talked about matters of principle.”

  “Did they hurt anyone but Earrin?”

  “Zhamia was speared, but not as badly damaged as your husband — Mort knocked the fellow out with a rock before he could finish the job. Genda was knocked unconscious, but is awake again and doesn’t seem to have changed. The only one of the other side really damaged was the one Mort handled.

  The others were mostly too smart to fight, and put down their spears.”

  “After wounding Earrin.”

  “Of course.” Kahvi was silent, then turned to enter the jail.

  “Don’t tell me which one it was,” she said as she went down the steps. “I’ve already done enough things that made me sick.” She ducked under the surface.

  Earrin and the other injured ones, except Genda, were on the floor inside, thoroughly bandaged. Her husband was extremely pale, but was conscious and grinned as he saw Kahvi. Disregarding the air, she pulled off her mask, knelt down and kissed him.”You’re sure you’re all right,” she said when she could finally speak. Nomad honesty dictated the answer.

  “No, I’m quite messed up,” he admitted. “I seem likely to live, though. It will be quite a while before I can row or pole a raft, I expect.” He indicated his left side, where a glass spearhead had severed muscles below the ribs. The arm and leg on the same side were also bandaged. “Yes, it hurts, so restrain yourself — that kiss was fun, but there can be too much of other good things than oxygen.”

  “At least, the troubles are over for now,” she said. “These delinquents who think the rules were made to keep them from enjoying themselves-”

  “That’s not fair,” Earrin pointed out. “They’re kids who had trouble believing the same things which you and I haven’t believed for a long time either. Seven years ago, Genda would have put you in their class.”

  “Seven years ago Genda did, the old-scientist. I’ve been wondering when she’d recognize me, but of course she hasn’t seen me indoors yet.”

  “Don’t use scientist as a swear word — It distorts your facts. Yes, if Danna’s all right, and I assume she is or you wouldn’t be in here, the trouble does seem to be over. Of course, we don’t have any more orders for glass and such things; we’ll have to think of something else the devout Hillers will buy-or maybe you just want to settle down on Milton or at Copper and live on what we can grow and make ourselves.”

  “There’s something to be said for that,” the woman admitted, “at least for a few months. Still, roaming around and learning thin
gs with Bones is really more fun, and I think it’s better for Danna.”

  “All right. I think I agree, luckily for me. We don’t have to settle it completely right now, though. Say, where’s Genda? I thought she got hurt in this scuffle, too.”

  “Not enough-pardon me.” Zhamia didn’t really sound embarrassed. “She was hit on the head, but seems to be over it. She went outside; she has work to do.”

  “Oh?” Kahvi and Earrin’s voices sounded together.

  “She’s taking a group to Hemenway to clean out that — laboratory, if you don’t mind the word. I guess you Nomads don’t very much.”

  “She doesn’t like the idea of a world where you can walk around outdoors without special equipment?”

  “Do you?” asked Kahvi, in a tone which Earrin should have recognized.

  “It would take some getting used to, I admit, he said slowly. “It would leave a lot of time for other things, though. Just think — ”

  “I’ve been thinking,” Kahvi said firmly. “In the first place, it wouldn’t work. I can’t believe that anything these young devils planned could really work. They take the easy solution, without caring who gets hurt; and as one of the people who did get hurt, and the mother of another, I’m not impressed by their planning. I know about ecological equilibrium and the population expansion of organisms without natural enemies, but I don’t believe this nitrate-reducing spore of theirs can get anywhere. It’ll just speed up the nitrate makers. Anyone knows that sort of interaction. I admit Genda is an irritating woman, but for once I’m willing to help her.”

  “Tell Bones. Maybe he’ll help too,” suggested her husband.

  “You’re joking-but I will. I think you still like the idea, you silly-” Earrin interrupted her with a squeeze from his able arm.

  “I do think it would be fun, but credit me with basic common sense,” he said gently. “Go ahead and tell Bones-and send him in here afterward, won’t you? I’m sure he’d be curious about human physiology as revealed by these spear slashes. He’d like to compare them with what the same weapons did to him and his partner.”