And it was quite obvious where they were. There remained just the small, practical problem of getting in touch with a group of scientists who had been-warned that a dangerous criminal might still be loose on Earth, without being killed by them. The messages at the ship were useless; the scientists might possibly visit it once a year, if they felt they could spare the time. Another message had to be delivered, but not to the ship. The place was obvious now, and the Hunter was angry with himself for not thinking of it earlier. The method of delivery was almost as obvious, but the Hunter rather hoped that his human colleagues would make themselves look as foolish as he himself had done. He was quite frank about this, when the entire in-group except Andre were gathered in Maeta's hospital room the night of their rescue from Eight. The girl had quickly mastered the art of relaying what he said to her, without having to pause to listen to him, and the exposition went smoothly.

"First," he started with a question, "is young Andre safely asleep? He's displayed more skill than I like at hearing what isn't meant for him."

"He's in the next room, but sound asleep," Seever replied. "He was uncomfortable enough to accept medication."

"And you're absolutely sure he took it?"

"Yes. I watched him drink it, made sure it wasn't spilled anywhere, and had him talk to me afterward to be sure his mouth was empty. I'm learning, old as I am."

"All right," Maeta relayed. "I am now quite sure I know where to get in touch with the evaluation team from my home world, and we should be able to do it tomorrow. I feel very silly at not seeing it before, and wasting so much of everyone's time and effort, not to mention extending the danger to Bob's life and bringing danger to Jenny and Mae. I want to go through my detailed idea of what has happened on Ell during the last seven years, not because I feel the need for drama but because if I can get through the account without any of you seeing where my people must be, I won't have to feel so foolish. Several mystery novels which Bob had read suggested the technique to me; forgive me if the suspense makes any of you uncomfortable.

"When we disposed of my original quarry-and it seems that we really did dispose of him, Doctor, and though absolute proof would be hard to supply, I examined Andre carefully-I was convinced that I was hopelessly lost from my own people. I had an unrealistic idea of the number of stars in the volume of s.p.a.ce whose radius I had traversed. I don't blame myself greatly; a view of the star clouds of the Milky Way is extremely deceptive. Look at a photograph in any of your popular astronomy books; you will certainly not realize that a fair model of this part of the galaxy could he made by scattering tennis b.a.l.l.s with an average separation of a thousand miles.

"After Bob and I had taken an astronomy course while he was in college, I realized that it should actually be quite simple for my people to trace us, and that a search had most probably been conducted. I am now quite sure that one of our ships reached Earth some, time before March, 1949-your data, Mae-within fifteen months after we disposed of my quarry. They detected his ship but not mine, probably because mine was far more badly damaged, and sea water had reached and corroded the units whose force fields are normally detectable from a distance. They investigated his ship, identified it, explored his possible paths to Ell, and found the generator case on Apu, just as we had earlier.

They had, after all, the advantage of knowing that such an object was missing from his ship, and must have looked for it specifically.

"Not finding any trace of me or my ship, they a.s.sumed that I had either failed to reach Earth at all, or had been killed by the crash, by Earth life, or by my quarry. It is also possible that they did find my ship, and deduced from its condition that I had never reached sh.o.r.e."

"But how could you have been killed by the crash?" asked Mrs.

Kinnaird. "As I understand it, your ship was merely flattened, not burned or exploded. Merely mashing you up wouldn't kill you."

"You exaggerate a little," replied the Hunter, "but what probably would have killed me was the marine life. I told Bob and Jenny about my troubles while I was down in the pipe. If I hadn't met that shark, I might very well not have survived to reach Ell and find Bob." The woman nodded understanding and the alien went on.

"In any case, my friends a.s.sumed that I was out of the picture, and that my quarry was loose somewhere on Earth-they hoped, but could not be sure, on Ell.

"Naturally they didn't find him. I suppose it's lucky they didn't find me, under the circ.u.mstances, though I might possibly have been able to identify myself to them in time. Anyway, they concluded the unsuccessful search, b.o.o.by-trapped my quarry's ship, and went back home. Their report caused an evaluation team to be a.s.sembled and sent here. They arrived over three years ago-again from your data, Mae."

"I don't see that," the girl said, interrupting her own translation.

"I'm delighted. You will. I skipped one point; sorry. The police would have been the ones to move the generator shield, partly to experiment with it, to see why our quarry might have left it where he did, partly to prevent him from using it again too easily-he might, for all they could know, have been wandering around on Apu at the time. One of them would have stayed with it, probably armed with a paralyzer, in case the other did find it; but what happened was Maeta's picking it up."

"You mean one of your people was inside that thing when I took it home?" Maeta exclaimed.

"I'd be glad to bet any reasonable sum you like; and considering the date you found it, I'm sure it was one of the police group, not the later arrivals. You didn't look inside, I take it."

"Not carefully. It seemed to be full of sand, and I left it outdoors to dry out before I took it into the house."

"Exactly. Into your house. One of your family, probably you, became host for a time to that policeman."

"But he never tried to talk to me!"

"Of course not. No emergency. He didn't find him self isolated halfway around your planet at his first chance to look through your eyes, as I did." The Hunter addressed the entire group again.

"I doubt that he stayed with Mae very long; he'd have wanted to move around a lot in his investigation. There must be a lot of ex- hosts around Ell at the mo ment.

"The next group eventually came, and started where the police had left off. They probably paid little if any attention to the b.o.o.by- trapped ship. I'm sorry about that, as I said; it was a reasonable theory originally, but general procedures have to be modified by specific situations. My mistake was in taking too long to see how the specific situations applied. Any way, the evaluation team came, and is here now. They're doing a job likely to take five or ten of your years. If the police reported human beings to be as different as they should have, there are probably fifty or so members of the team-including several of the specialists we need to get Bob back together. We'll take a note to their headquarters tomorrow."

"Where's that?' asked Jenny.

"I'll go along with your game, Hunter," said Maeta. "You implied that I'd served as a host another time. Is that relevant to your Agatha Christie puzzle? Bob, did you, ever feel this creature grinning?"

"Cant say that I did," was, the answer. "Let him go on."

The detective continued. "It is very relevant. I expect one of you to come up with the answer at any moment. Yes, Maeta, you were a host, probably several times. I suppose they shifted hosts often to avoid doing what I did to Bob-as I should have one, I see now.

At least once, you had an expert who could manipulate the desalting operation; you were quite right, you really didn't get thirsty that time you were stranded on the reef."

"But why would they use me several times? There are a couple of hundred people on Ell-at least a hundred and fifty even if a lot of the children are too small."

"A strong and healthy host is very desirable; spending all our time in protection and repair is hardly life. We like to do things of our own, and the evaluation team members would have a great deal to do. Much more to the point, Mae," the girl continued to trans late in spite of the personal nature of the next sentences, "you are one of the most conveniently located and occupied people on this island, for any member of the headquarters group of the evaluation team. Think, Miss Teroa. A s.p.a.ce where an enormous volume of information about Earth and its people is stored in organized form. A place where a host can conveniently be made to feel sleepy if the symbiont wants to work alone for a time, and where a human being can un.o.btrusively be anesthetized briefly with out risking his falling and hurting himself, if one of the team needs to spend a while with a host. You told Bob it was a very comfortable chair."

Maeta had not yet achieved Bob's skill at communicating with the Hunter without speaking aloud, but she tried.

"That last gives Bob and me an unfair advantage, don't you think? I see it now. Should I speak up?"

"Bob hasn't Go ahead." The girl nodded, and spoke aloud.

"All right Doctor, if you can lend me a crutch, I'll go to work tomorrow. There's still plenty to be done downstairs. If the Hunter will write a note in his own language tonight, I'll tuck it into that chair that Old Toke found too comfortable; and some time during the morning I'll take a rest in it. Maybe a larger sign that I can prop up on the table, so it can be read from the sides of the room, calling attention to the note in the chair, would also be a good idea.

If I hear anyone coming, I can slip it under a book, so there won't be any violation of the rules. All right, Hunter?"

It was quite all right

15. Official, from Headquarters

The Hunter's princ.i.p.al trouble, though not his only one, during the next several months stemmed from the personality of the specialist who took over Bob. This being was an intolerant and tactless individual who attached much weight to professional competence, had a high-fortunately justified-opinion of his own abilities, and failed completely to see how the detective could have been so stupid as to remain with a single host of a new species for such a long time. Since the Hunter had no excuse and had al ready been blaming himself for the slip, his own self-esteem was not healing at all rapidly. The fact that Bob disliked his new symbiont, made no bones about saying so, and openly looked forward to the time when he could have the Hunter back was some com fort to the latter, but not very much. Fortunately this att.i.tude made no difference to the specialist, who regarded the young man as an interesting specimen, not a personal friend. The closest he came to approving of anything the Hunter had done made this more than clear.

The two were in direct contact, a situation which permitted their multi-purpose "cells" to act as nerves and transmit information between them at speeds far greater than oral speech could manage. The Hunter, was in the library chair; Bob' was seated there to permit the communication, carefully keeping his hands motionless on the stuffed arms.

"I must admit," the xen.o.biologist said, "that there has been one good result of your stupidity. I have been able to find out more about this species in a few months, from the various things you did to this being, than I could have ascertained from several years of legal experimentation. It is quite possible that in two or three more years I will be able to resolve the techniques which will allow us to live full time with these beings."

"Then Bob is going to be all right? You expect to be able to study him for years?"

"Of course. Isn't that what I implied? You are allowing yourself to be distracted from straightforward joint thinking."

"Why didn't you tell me sooner?"

"It was not important," said Xeno, as Bob had named him.

"It was to me," returned the Hunter. "You sound like one of those unreal scientists in the stories Bob reads. Do you know what a friend is?"

"Certainly. I have a number of friends myself but your forming a close attachment to a member of this species was rather premature. In any case, it will be several years before I can allow you to resume symbiosis with this one. If you plan to remain on Earth, you should start living with other human beings I can permit you to practice, but you are not to re main with any individual for more than half of one of their years. I suppose you will want to confine yourself to those who, as a result of your incompetence, already know about us."

"It would be a lot better than living in this library, even if the food does come regularly now-you'll have to admit that's an improvement on silverfish and the crumbs from librarians'

lunches."

"It is more convenient, I grant. I trust you are not developing this highly subjective att.i.tude human beings call taste, however.

Food is fuel; as long as the quant.i.ty is sufficient, there is no reason to complain."

The Hunter broke contact, Xeno informed Bob that the conversation was over-the alien had learned English in connection with his evaluation work in the library-and the detective had no contact with the specialist for several days.

He spent some of the time with Maeta, whose in juries were completely healed, and reported Xenon's words to her.

"Then Bob is really going to be all right?" she asked. "He's looked so much happier, and doesn't have the fatigue or the joint pains any more, but I couldn't be sure that Xeno had really gotten to the cause of things."

"He knew that from the beginning," the Hunter ad mitted. "The problem was that I'd done so much dam age that there was no certainty for a long time that it could be repaired. I thought I'd admitted that to you."

"You did," conceded the girl, "but I was hoping you'd forgotten.

You were feeling pretty awful about the whole thing, and it wasn't really your fault. You couldn't have done anything else."

"Not at first," the alien admitted, "but later on I should have swapped around to other hosts. There were Bob's parents, and the doctor, who knew about me."

"Would you need that many? Wouldn't just back and forth between two people be all right?"

"I'd think so, but I'm not sure. I could ask Xeno. But isn't it rather academic now, anyway?"

"Not entirely," Maeta said. "You find out-and make sure when that cold-blooded molecule manipulator is going to be through with Bob, while you're at it. I think I can hold hands with him long enough for you two to get that much of a message across. Now think over those lessons in biochem that Xeno ordered you to memorize; I have book work to do."

About the Author.

Hal Clement (Harry Clement Stubbs) was born in Ma.s.sachusetts in 1922. He has been a science lover from early childhood, at least partly as a result of a 1930 Buck Rogers panel in which villains were "headed for Mars, forty-seven million miles away." His father, an accountant, couldn't answer the resulting questions, and led little Hal to the local library. The result was irreversible brain influence.

He majored in astronomy at Harvard, and has since acquired master's degrees in education and in chemistry. He earns his basic living as a teacher of chemistry and astronomy at Milton Academy, in Ma.s.sachusetts, and regards science-fiction writing and painting as hobbies. His first two stories, "Proof" and "Impediment," were sold when he was a junior in college; their impression on Harvard's $400 yearly tuition secured family tolerance for that crazy Buck Rogers stuff.

He has since produced half a dozen novels, of which the best known are Needle and Mission of Gravity. His reputation among science-fiction enthusiasts is that of a "bard" writer-one who tries to stick faithfully to the physical sciences as they are currently understood; like Arthur C. Clarke and the late w.i.l.l.y Ley, Clement would never dream of having a s.p.a.ce ship fall into the sun merely because its engines broke down. He can do his own orbit com puting, and does.

He leads a double life, appearing frequently at science fiction conventions as Hal Clement and spending the rest of his time in Milton as Harry Stubbs, the rather square science teacher with a wife of twenty-five years and three grown children. He does occasional merit badge counseling for the Boy Scouts, has served on his town's finance committee, and is an eleven-gallon Red Cross blood donor.