Illustrated by DIEHL

The price of life was a life for a life—which was all the reward the victim looked for!

His hands were shaking as he exhibited the gifts. If he were on Earth, he would be certain it was the flu; in the Centaurus system, kranken. But this was Van Daamas, so Lee Bolden couldn't say what he had. Man hadn't been here long enough to investigate the diseases with any degree of thoroughness. There were always different hazards to overcome as new planets were settled.

But whatever infection he had, Bolden was not greatly concerned as he counted out the gifts. He had felt the onset of illness perhaps an hour before. When he got back to the settlement he'd be taken care of. That was half a day's flight from here. The base was equipped with the best medical facilities that had been devised.

He stacked up the gifts to make an impressive show: five pairs of radar goggles, seven high-velocity carbines, seven boxes of ammunition. This was the natives' own rule and was never to be disregarded—it had to be an odd number of gifts.

The Van Daamas native gazed impassively at the heap. He carried a rather strange bow and a quiver was strapped to his thigh. With one exception, the arrows were brightly colored, mostly red and yellow. Bolden supposed this was for easy recovery in case the shot missed. But there was always one arrow that was stained dark blue. Bolden had observed this before—no native was ever without that one somber-looking arrow.

The man of Van Daamas stood there and the thin robe that was no protection against the elements rippled slightly in the chill current of air that flowed down the mountainside. "I will go talk with the others," he said in English.

"Go talk," said Bolden, trying not to shiver. He replied in native speech, but a few words exhausted his knowledge and he had to revert to his own language. "Take the gifts with you. They are yours, no matter what you decide."

The native nodded and reached for a pair of goggles. He tried them on, looking out over fog and mist-shrouded slopes. These people of Van Daamas needed radar less than any race Bolden knew of. Living by preference in mountains, they had developed a keenness of vision that enabled them to see through the perpetual fog and mist far better than any Earthman. Paradoxically it was the goggles they appreciated most. Extending their sight seemed more precious to them than powerful carbines.

The native shoved the goggles up on his forehead, smiling with pleasure. Noticing that Bolden was shivering, he took his hands and examined them. "Hands sick?" he queried.

"A little," said Bolden. "I'll be all right in the morning."

The native gathered up the gifts. "Go talk," he repeated as he went away.

Lee Bolden sat in the copter and waited. He didn't know how much influence this native had with his people. He had come to negotiate, but this might have been because he understood English somewhat better than the others.

A council of the natives would make the decision about working for the Earthmen's settlement. If they approved of the gifts, they probably would. There was nothing to do now but wait—and shiver. His hands were getting numb and his feet weren't much better.

Presently the native came out of the fog carrying a rectangular wicker basket. Bolden was depressed when he saw it. One gift in return for goggles, carbines, ammunition. The rate of exchange was not favorable. Neither would the reply be.

The man set the basket down and waited for Bolden to speak. "The people have talked?" asked Bolden.

"We have talked to come," said the native, holding out his fingers. "In five or seven days, we come."

It was a surprise, a pleasant one. Did one wicker basket equal so many fine products of superlative technology? Apparently it did. The natives had different values. To them, one pair of goggles was worth more than three carbines, a package of needles easily the equivalent of a box of ammunition.

"It's good you will come. I will leave at once to tell them at the settlement," said Bolden. There was something moving in the basket, but the weave was close and he couldn't see through it.

"Stay," the man advised. "A storm blows through the mountains."

"I will fly around the storm," said Bolden.

If he hadn't been sick he might have accepted the offer. But he had to get back to the settlement for treatment. On a strange planet you never could tell what might develop from a seemingly minor ailment. Besides he'd already been gone two days searching for this tribe in the interminable fog that hung over the mountains. Those waiting at the base would want him back as soon as he could get there.

"Fly far around," said the man. "It is a big storm." He took up the basket and held it level with the cabin, opening the top. An animal squirmed out and disappeared inside.

Bolden looked askance at the eyes that glowed in the dim interior. He hadn't seen clearly what the creature was and he didn't like the idea of having it loose in the cabin, particularly if he had to fly through a storm. The man should have left it in the basket. But the basket plus the animal would have been two gifts—and the natives never considered anything in even numbers.

"It will not hurt," said the man. "A gentle pet."

As far as he knew, there were no pets and very few domesticated animals. Bolden snapped on the cabin light. It was one of those mysterious creatures every tribe kept in cages near the outskirts of their camps. What they did with them no one knew and the natives either found it impossible to explain or did not care to do so.

It seemed unlikely that the creatures were used for food and certainly they were not work animals. And in spite of what this man said, they were not pets either. No Earthman had ever seen a native touch them nor had the creatures ever been seen wandering at large in the camp. And until now, none had been permitted to pass into Earth's possession. The scientists at the settlement would regard this acquisition with delight.

"Touch it," said the native.

Bolden held out his trembling hand and the animal came to him with alert and friendly yellow eyes. It was about the size of a rather small dog, but it didn't look much like one. It resembled more closely a tiny slender bear with a glossy and shaggy cinnamon coat. Bolden ran his hands through the clean-smelling fur and the touch warmed his fingers. The animal squirmed and licked his fingers.

"It has got your taste," said the native. "Be all right now. It is yours." He turned and walked into the mist.

Bolden got in and started the motors while the animal climbed into the seat beside him. It was a friendly thing and he couldn't understand why the natives always kept it caged.

He headed straight up, looking for a way over the mountains to avoid the impending storm. Fog made it difficult to tell where the peaks were and he had to drop lower, following meandering valleys. He flew as swiftly as limited visibility would allow, but he hadn't gone far when the storm broke. He tried to go over the top of it, but this storm seemed to have no top. The region was incompletely mapped and even radar wasn't much help in the tremendous electrical display that raged around the ship.

His arms ached as he clung to the controls. His hands weren't actually cold, they were numb. His legs were leaden. The creature crept closer to him and he had to nudge it away. Momentarily the distraction cleared his head. He couldn't put it off any longer. He had to land and wait out the storm—if he could find a place to land.

Flexing his hands until he worked some feeling into them, he inched the ship lower. A canyon wall loomed at one side and he had to veer away and keep on looking.

Eventually he found his refuge—a narrow valley where the force of the winds was not extreme—and he set the land anchor. Unless something drastic happened, it would hold.

He made the seat into a bed, decided he was too tired to eat, and went directly to sleep. When he awakened, the storm was still raging and the little animal was snoozing by his side.

He felt well enough to eat. The native hadn't explained what the animal should be fed, but it accepted everything Bolden offered. Apparently it was as omnivorous as Man. Before lying down again, he made the other seat into a bed, although it didn't seem to matter. The creature preferred being as close to him as it could get and he didn't object. The warmth was comforting.

Alternately dozing and waking he waited out the storm. It lasted a day and a half. Finally the sun was shining. This was two days since he had first fallen ill, four days after leaving the settlement.

Bolden felt much improved. His hands were nearly normal and his vision wasn't blurred. He looked at the little animal curled in his lap, gazing up at him with solemn yellow eyes. If he gave it encouragement it would probably be crawling all over him. However, he couldn't have it frisking around while he was flying. "Come, Pet," he said—there wasn't anything else to call it—"you're going places."

Picking it up, half-carrying and half-dragging it, he took it to the rear of the compartment, improvising a narrow cage back there. He was satisfied it would hold. He should have done this in the beginning. Of course he hadn't felt like it then and he hadn't had the time—and anyway the native would have resented such treatment of a gift. Probably it was best he had waited.

His pet didn't like confinement. It whined softly for a while. The noise stopped when the motors roared. Bolden headed straight up, until he was high enough to establish communication over the peaks. He made a brief report about the natives' agreement and his own illness, then he started home.

He flew at top speed for ten hours. He satisfied his hunger by nibbling concentrated rations from time to time. The animal whined occasionally, but Bolden had learned to identify the sounds it made. It was neither hungry nor thirsty. It merely wanted to be near him. And all he wanted was to reach the base.

The raw sprawling settlement looked good as he sat the copter down. Mechanics came running from the hangars. They opened the door and he stepped out.

And fell on his face. There was no feeling in his hands and none in his legs. He hadn't recovered.

Doctor Kessler peered at him through the microscreen. It gave his face a narrow insubstantial appearance. The microscreen was a hemispherical force field enclosing his head. It originated in a tubular circlet that snapped around his throat at the top of the decontagion suit. The field killed all microlife that passed through it or came in contact with it. The decontagion suit was non-porous and impermeable, covering completely the rest of his body. The material was thinner over his hands and thicker at the soles.

Bolden took in the details at a glance. "Is it serious?" he asked, his voice cracking with the effort.

"Merely a precaution," said the doctor hollowly. The microscreen distorted sound as well as sight. "Merely a precaution. We know what it is, but we're not sure of the best way to treat it."

Bolden grunted to himself. The microscreen and decontagion suit were strong precautions.

The doctor wheeled a small machine from the wall and placed Bolden's hand in a narrow trough that held it steady. The eyepiece slid into the microscreen and, starting at the finger tips, Kessler examined the arm, traveling slowly upward. At last he stopped. "Is this where feeling ends?"

"I think so. Touch it. Yeah. It's dead below there."

"Good. Then we've got it pegged. It's the Bubble Death."

Bolden showed concern and the doctor laughed. "Don't worry. It's called that because of the way it looks through the X-ray microscope. It's true that it killed the scouting expedition that discovered the planet, but it won't get you."

"They had antibiotics. Neobiotics, too."

"Sure. But they had only a few standard kinds. Their knowledge was more limited and they lacked the equipment we now have."

The doctor made it sound comforting. But Bolden wasn't comforted. Not just yet.

"Sit up and take a look," said Kessler, bending the eyepiece around so Bolden could use it. "The dark filamented lines are nerves. See what surrounds them?"

Bolden watched as the doctor adjusted the focus for him. Each filament was covered with countless tiny spheres that isolated and insulated the nerve from contact. That's why he couldn't feel anything. The spherical microbes did look like bubbles. As yet they didn't seem to have attacked the nerves directly.

While he watched, the doctor swiveled out another eyepiece for his own use and turned a knob on the side of the machine. From the lens next to his arm an almost invisible needle slid out and entered his flesh. Bolden could see it come into the field of view. It didn't hurt. Slowly it approached the dark branching filament, never quite touching it.

The needle was hollow and as Kessler squeezed the knob it sucked in the spheres. The needle extended a snout which crept along the nerve, vacuuming in microbes as it moved. When a section had been cleansed, the snout was retracted. Bolden could feel the needle then.

When the doctor finished, he laid Bolden's hand back at his side and wheeled the machine to the wall, extracting a small capsule which he dropped into a slot that led to the outside. He came back and sat down.

"Is that what you're going to do?" asked Bolden. "Scrape them off?"

"Hardly. There are too many nerves. If we had ten machines and enough people to operate them, we might check the advance in one arm. That's all." The doctor leaned back in the chair. "No. I was collecting a few more samples. We're trying to find out what the microbes react to."

"More samples? Then you must have taken others."

"Certainly. We put you out for a while to let you rest." The chair came down on four legs. "You've got a mild case. Either that or you have a strong natural immunity. It's now been three days since you reported the first symptoms and it isn't very advanced. It killed the entire scouting expedition in less time than that."

Bolden looked at the ceiling. Eventually they'd find a cure. But would he be alive that long?

"I suspect what you're thinking," said the doctor. "Don't overlook our special equipment. We already have specimens in the sonic accelerator. We've been able to speed up the life processes of the microbes about ten times. Before the day is over we'll know which of our anti and neobiotics they like the least. Tough little things so far—unbelievably tough—but you can be sure we'll smack them."

His mind was active, but outwardly Bolden was quiescent as the doctor continued his explanation.

The disease attacked the superficial nervous system, beginning with the extremities. The bodies of the crew of the scouting expedition had been in an advanced state of decomposition when the medical rescue team reached them and the microbes were no longer active. Nevertheless it was a reasonable supposition that death had come shortly after the invading bacteria had reached the brain. Until then, though nerves were the route along which the microbes traveled, no irreparable damage had been done.

This much was good news. Either he would recover completely or he would die. He would not be crippled permanently. Another factor in his favor was the sonic accelerator. By finding the natural resonance of the one-celled creature and gradually increasing the tempo of the sound field, the doctor could grow and test ten generations in the laboratory while one generation was breeding in the body. Bolden was the first patient actually being observed with the disease, but the time element wasn't as bad as he had thought.

"That's where you are," concluded Kessler. "Now, among other things, we've got to find where you've been."

"The ship has an automatic log," said Bolden. "It indicates every place I landed."

"True, but our grid coordinates are not exact. It will be a few years before we're able to look at a log and locate within ten feet of where a ship has been." The doctor spread out a large photomap. There were several marks on it. He fastened a stereoscope viewer over Bolden's eyes and handed him a pencil. "Can you use this?"

"I think so." His fingers were stiff and he couldn't feel, but he could mark with the pencil. Kessler moved the map nearer and the terrain sprang up in detail. In some cases, he could see it more clearly than when he had been there, because on the map there was no fog. Bolden made a few corrections and the doctor took the map away and removed the viewer.

"We'll have to stay away from these places until we get a cure. Did you notice anything peculiar in any of the places you went?"

"It was all mountainous country."

"Which probably means that we're safe on the plain. Were there any animals?"

"Nothing that came close. Birds maybe."

"More likely it was an insect. Well, we'll worry about the host and how it is transmitted. Try not to be upset. You're as safe as you would be on Earth."

"Yeah," said Bolden. "Where's the pet?"

The doctor laughed. "You did very well on that one. The biologists have been curious about the animal since the day they saw one in a native camp."

"They can look at it as much as they want," said Bolden. "Nothing more on this one, though. It's a personal gift."

"You're sure it's personal?"

"The native said it was."

The doctor sighed. "I'll tell them. They won't like it, but we can't argue with the natives if we want their cooperation."

Bolden smiled. The animal was safe for at least six months. He could understand the biologists' curiosity, but there was enough to keep them curious for a long time on a new planet. And it was his. In a remarkably short time, he had become attached to it. It was one of those rare things that Man happened across occasionally—about once in every five planets. Useless, completely useless, the creature had one virtue. It liked Man and Man liked it. It was a pet. "Okay," he said. "But you didn't tell me where it is."

The doctor shrugged, but the gesture was lost in the shapeless decontagion suit. "Do you think we're letting it run in the streets? It's in the next room, under observation."

The doctor was more concerned than he was letting on. The hospital was small and animals were never kept in it. "It's not the carrier. I was sick before it was given to me."

"You had something, we know that much, but was it this? Even granting that you're right, it was in contact with you and may now be infected."

"I think life on this planet isn't bothered by the disease. The natives have been every place I went and none of them seemed to have it."

"Didn't they?" said the doctor, going to the door. "Maybe. It's too early to say." He reeled a cord out of the wall and plugged it into the decontagion suit. He spread his legs and held his arms away from his sides. In an instant, the suit glowed white hot. Only for an instant, and it was insulated inside. Even so it must be uncomfortable—and the process would be repeated outside. The doctor wasn't taking any chances. "Try to sleep," he said. "Ring if there's a change in your condition—even if you think it's insignificant."

"I'll ring," said Bolden. In a short time he fell asleep. It was easy to sleep.

The nurse entered as quietly as she could in the decontagion outfit. It awakened Bolden. It was evening. He had slept most of the day. "Which one are you?" he asked. "The pretty one?"

"All nurses are pretty if you get well. Here. Swallow this."

It was Peggy. He looked doubtfully at what she held out. "All of it?"

"Certainly. You get it down and I'll see that it comes back up. The string won't hurt you."

She passed a small instrument over his body, reading the dial she held in the other hand. The information, he knew, was being recorded elsewhere on a master chart. Apparently the instrument measured neural currents and hence indirectly the progress of the disease. Already they had evolved new diagnostic techniques. He wished they'd made the same advance in treatment.

After expertly reeling out the instrument he had swallowed, the nurse read it and deposited it in a receptacle in the wall. She brought a tray and told him to eat. He wanted to question her, but she was insistent about it so he ate. Allowance had been made for his partial paralysis. The food was liquid. It was probably nutritious, but he didn't care for the taste.

She took the tray away and came back and sat beside him. "Now we can talk," she said.

"What's going on?" he said bluntly. "When do I start getting shots? Nothing's been done for me so far."

"I don't know what the doctor's working out for you. I'm just the nurse."

"Don't try to tell me that," he said. "You're a doctor yourself. In a pinch you could take Kessler's place."

"And I get my share of pinches," she said brightly. "Okay, so I'm a doctor, but only on Earth. Until I complete my off-planet internship here, I'm not allowed to practice."

"You know as much about Van Daamas as anyone does."

"That may be," she said. "Now don't be alarmed, but the truth ought to be obvious. None of our anti or neobiotics or combinations of them have a positive effect. We're looking for something new."

It should have been obvious; he had been hoping against that, though. He looked at the shapeless figure sitting beside him and remembered Peggy as she usually looked. He wondered if they were any longer concerned with him as an individual. They must be working mainly to keep the disease from spreading. "What are my chances?"

"Better than you think. We're looking for an additive that will make the biotics effective."

He hadn't thought of that, though it was often used, particularly on newly settled planets. He had heard of a virus infection common to Centaurus that could be completely controlled by a shot of neobiotics plus aspirin, though separately neither was of any value. But the discovery of what substance should be added to what antibiotic was largely one of trial and error. That took time and there wasn't much time. "What else?" he said.

"That's about it. We're not trying to make you believe this isn't serious. But don't forget we're working ten times as fast as the disease can multiply. We expect a break any moment." She got up. "Want a sedative for the night?"

"I've got a sedative inside me. Looks like it will be permanent."

"That's what I like about you, you're so cheerful," she said, leaning over and clipping something around his throat. "In case you're wondering, we're going to be busy tonight checking the microbe. We can put someone in with you, but we thought you'd rather have all of us working on it."

"Sure," he said.

"This is a body monitor. If you want anything just call and we'll be here within minutes."

"Thanks," he said. "I won't panic tonight."

She plugged in the decontagion uniform, flashed it on and then left the room. After she was gone, the body monitor no longer seemed reassuring. It was going to take something positive to pull him through.

They were going to work through the night, but did they actually hope for success. What had Peggy said? None of the anti or neobiotics had a positive reaction. Unknowingly she had let it slip. The reaction was negative; the bubble microbes actually grew faster in the medium that was supposed to stop them. It happened occasionally on strange planets. It was his bad luck that it was happening to him.

He pushed the thoughts out of his mind and tried to sleep. He did for a time. When he awakened he thought, at first, it was his arms that had aroused him. They seemed to be on fire, deep inside. To a limited extent, he still had control. He could move them though there was no surface sensation. Interior nerves had not been greatly affected until now. But outside the infection had crept up. It was no longer just above the wrists. It had reached his elbows and passed beyond. A few inches below his shoulder he could feel nothing. The illness was accelerating. If they had ever thought of amputation, it was too late, now.

He resisted an impulse to cry out. A nurse would come and sit beside him, but he would be taking her from work that might save his life. The infection would reach his shoulders and move across his chest and back. It would travel up his throat and he wouldn't be able to move his lips. It would paralyze his eyelids so that he couldn't blink. Maybe it would blind him, too. And then it would find ingress to his brain.

The result would be a metabolic explosion. Swiftly each bodily function would stop altogether or race wildly as the central nervous system was invaded, one regulatory center after the other blanking out. His body would be aflame or it would smolder and flicker out. Death might be spectacular or it could come very quietly.

That was one reason he didn't call the nurse.

The other was the noise.

It was a low sound, half purr, half a coaxing growl. It was the animal the native had given him, confined in the next room. Bolden was not sure why he did what he did next. Instinct or reason may have governed his actions. But instinct and reason are divisive concepts that cannot apply to the human mind, which is actually indivisible.

He got out of bed. Unable to stand, he rolled to the floor. He couldn't crawl very well because his hands wouldn't support his weight so he crept along on his knees and elbows. It didn't hurt. Nothing hurt except the fire in his bones. He reached the door and straightened up on his knees. He raised his hand to the handle, but couldn't grasp it. After several trials, he abandoned the attempt and hooked his chin on the handle, pulling it down. The door opened and he was in the next room. The animal was whining louder now that he was near. Yellow eyes glowed at him from the corner. He crept to the cage.

It was latched. The animal shivered eagerly, pressing against the side, striving to reach him. His hands were numb and he couldn't work the latch. The animal licked his fingers.

It was easier after that. He couldn't feel what he was doing, but somehow he managed to unlatch it. The door swung open and the animal bounded out, knocking him to the floor.

He didn't mind at all because now he was sure he was right. The natives had given him the animal for a purpose. Their own existence was meager, near the edge of extinction. They could not afford to keep something that wasn't useful. And this creature was useful. Tiny blue sparks crackled from the fur as it rubbed against him in the darkness. It was not whining. It rumbled and purred as it licked his hands and arms and rolled against his legs.

After a while he was strong enough to crawl back to bed, leaning against the animal for support. He lifted himself up and fell across the bed in exhaustion. Blood didn't circulate well in his crippled body. The animal bounded up and tried to melt itself into his body. He couldn't push it away if he wanted. He didn't want to. He stirred and got himself into a more comfortable position. He wasn't going to die.

In the morning, Bolden was awake long before the doctor came in. Kessler's face was haggard and the smile was something he assumed solely for the patient's benefit. If he could have seen what the expression looked like after filtering through the microscreen, he would have abandoned it. "I see you're holding your own," he said with hollow cheerfulness. "We're doing quite well ourselves."

"I'll bet," said Bolden. "Maybe you've got to the point where one of the antibiotics doesn't actually stimulate the growth of the microbes?"

"I was afraid you'd find it out," sighed the doctor. "We can't keep everything from you."

"You could have given me a shot of plasma and said it was a powerful new drug."

"That idea went out of medical treatment a couple of hundred years ago," said the doctor. "You'd feel worse when you failed to show improvement. Settling a planet isn't easy and the dangers aren't imaginary. You've got to be able to face facts as they come."

He peered uncertainly at Bolden. The microscreen distorted his vision, too. "We're making progress though it may not seem so to you. When a mixture of a calcium salt plus two antihistamines is added to a certain neobiotic, the result is that the microbe grows no faster than it should. Switching the ingredients here and there—maybe it ought to be a potassium salt—and the first thing you know we'll have it stopped cold."

"I doubt the effectiveness of those results," said Bolden. "In fact, I think you're on the wrong track. Try investigating the effects of neural induction."

"What are you talking about?" said the doctor, coming closer and glancing suspiciously at the lump beside Bolden. "Do you feel dizzy? Is there anything else unusual that you notice?"

"Don't shout at the patient." Bolden waggled his finger reprovingly. He was proud of the finger. He couldn't feel what he was doing, but he had control over it. "You, Kessler, should face the fact that a doctor can learn from a patient what the patient learned from the natives."

But Kessler didn't hear what he said. He was looking at the upraised hand. "You're moving almost normally," he said. "Your own immunity factor is controlling the disease."

"Sure. I've got an immunity factor," said Bolden. "The same one the natives have. Only it's not inside my body." He rested his hand on the animal beneath the covers. It never wanted to leave him. It wouldn't have to.

"I can set your mind at rest on one thing, Doctor. Natives are susceptible to the disease, too. That's why they were able to recognize I had it. They gave me the cure and told me what it was, but I was unable to see it until it was nearly too late. Here it is." He turned back the covers and the exposed animal sleeping peacefully on his legs which raised its head and licked his fingers. He felt that.

After an explanation the doctor tempered his disapproval. It was an unsanitary practice, but he had to admit that the patient was much improved. Kessler verified the state of Bolden's health by extensive use of the X-ray microscope. Reluctantly he wheeled the machine to the wall and covered it up.

"The infection is definitely receding," he said. "There are previously infected areas in which I find it difficult to locate a single microbe. What I can't understand is how it's done. According to you, the animal doesn't break the skin with its tongue and therefore nothing is released into the bloodstream. All that seems necessary is that the animal be near you." He shook his head behind the microscreen. "I don't think much of the electrical analogy you used."

"I said the first thing I thought of. I don't know if that's the way it works, but it seems to me like a pretty fair guess."

"The microbes do cluster around nerves," said the doctor. "We know that neural activity is partly electrical. If the level of that activity can be increased, the bacteria might be killed by ionic dissociation." He glanced speculatively at Bolden and the animal. "Perhaps you do borrow nervous energy from the animal. We might also find it possible to control the disease with an electrical current."

"Don't try to find out on me," said Bolden. "I've been an experimental specimen long enough. Take somebody who's healthy. I'll stick with the natives' method."

"I wasn't thinking of experiments in your condition. You're still not out of danger." Nevertheless he showed his real opinion when he left the room. He failed to plug in and flash the decontagion suit.

Bolden smiled at the doctor's omission and ran his hand through the fur. He was going to get well.

But his progress was somewhat slower than he'd anticipated though it seemed to satisfy the doctor who went on with his experiments. The offending bacteria could be killed electrically. But the current was dangerously large and there was no practical way to apply the treatment to humans. The animal was the only effective method.

Kessler discovered the microbe required an intermediate host. A tick or a mosquito seemed indicated. It would take a protracted search of the mountains to determine just what insect was the carrier. In any event the elaborate sanitary precautions were unnecessary. Microscreens came down and decontagion suits were no longer worn. Bolden could not pass the disease on to anyone else.

Neither could the animal. It seemed wholly without parasites. It was clean and affectionate, warm to the touch. Bolden was fortunate that there was such a simple cure for the most dreaded disease on Van Daamas.

It was several days before he was ready to leave the small hospital at the edge of the settlement. At first he sat up in bed and then he was allowed to walk across the room. As his activity increased, the animal became more and more content to lie on the bed and follow him with its eyes. It no longer frisked about as it had in the beginning. As Bolden told the nurse, it was becoming housebroken.

The time came when the doctor failed to find a single microbe. Bolden's newly returned strength and the sensitivity of his skin where before there had been numbness confirmed the diagnosis. He was well. Peggy came to walk him home. It was pleasant to have her near.

"I see you're ready," she said, laughing at his eagerness.

"Except for one thing," he said. "Come, Pet." The animal raised its head from the bed where it slept.

"Pet?" she said quizzically. "You ought to give it a name. You've had it long enough to decide on something."

"Pet's a name," he said. "What can I call it? Doc? Hero?"

She made a face. "I can't say I care for either choice, although it did save your life."

"Yes, but that's an attribute it can't help. The important thing is that if you listed what you expect of a pet you'd find it in this creature. Docile, gentle, lively at times; all it wants is to be near you, to have you touch it. And it's very clean."

"All right, call it Pet if you want," said Peggy. "Come on, Pet."

It paid no attention to her. It came when Bolden called, getting slowly off the bed. It stayed as close as it could get to Bolden. He was still weak so they didn't walk fast and, at first, the animal was able to keep up.

It was almost noon when they went out. The sun was brilliant and Van Daamas seemed a wonderful place to be alive in. Yes, with death behind him, it was a very wonderful place. Bolden chatted gaily with Peggy. She was fine company.

And then Bolden saw the native who had given him the animal. Five to seven days, and he had arrived on time. The rest of the tribe must be elsewhere in the settlement. Bolden smiled in recognition while the man was still at some distance. For an answer the native shifted the bow in his hand and glanced behind the couple, in the direction of the hospital.

The movement with the bow might have been menacing, but Bolden ignored that gesture. It was the sense that something was missing that caused him to look down. The animal was not at his side. He turned around.

The creature was struggling in the dust. It got to its feet and wobbled toward him, staggering crazily as it tried to reach him. It spun around, saw him, and came on again. The tongue lolled out and it whined once. Then the native shot it through the heart, pinning it to the ground. The short tail thumped and then it died.

Bolden couldn't move. Peggy clutched his arm. The native walked over to the animal and looked down. He was silent for a moment. "Die anyway soon," he said to Bolden. "Burned out inside."

He bent over. The bright yellow eyes had faded to nothingness in the sunlight. "Gave you its health," said the man of Van Daamas respectfully as he broke off the protruding arrow.

It was a dark blue arrow.

Now every settlement on the planet has Bolden's pets. They have been given a more scientific name, but nobody remembers what it is. The animals are kept in pens, exactly as is done by the natives, on one side of town, not too near any habitation.

For a while, there was talk that it was unscientific to use the animal. It was thought that an electrical treatment could be developed to replace it. Perhaps this was true. But settling a planet is a big task. As long as one method works there isn't time for research. And it works—the percentage of recovery is as high as in other common ailments.

But in any case the animal can never become a pet, though it may be in the small but bright spark of consciousness that is all the little yellow-eyed creature wants. The quality that makes it so valuable is the final disqualification. Strength can be a weakness. Its nervous system is too powerful for a man in good health, upsetting the delicate balance of the human body in a variety of unusual ways. How the energy-transfer takes place has never been determined exactly, but it does occur.

It is only when he is stricken with the Bubble Death and needs additional energy to drive the invading microbes from the tissue around his nerves that the patient is allowed to have one of Bolden's pets.

In the end, it is the animal that dies. As the natives knew, it is kindness to kill it quickly.

It is highly regarded and respectfully spoken of. Children play as close as they can get, but are kept well away from the pens by a high, sturdy fence. Adults walk by and nod kindly to it.

Bolden never goes there nor will he speak of it. His friends say he's unhappy about being the first Earthman to discover the usefulness of the little animal. They are right. It is a distinction he doesn't care for. He still has the blue arrow. There are local craftsmen who can mend it, but he has refused their services. He wants to keep it as it is.

—F. L. WALLACE