by Larry Niven
The interrupter circuit!
Svetz sat up. His head swam. He tried to stand, and overbalanced, and fell rolling.
The apparition braced its smoky feet against the control panel, heedless of the switches and dials. Its feet and ankles were terribly thin. It pantomimed frantic effort...but the lever marked EMERGENCY STOP did not move.
The figure turned to Svetz and screamed at him without sound. Svetz screamed back and threw his arms across his eyes. That face!
When Svetz dared look again, the thing was gone.
Svetz began to shake. The inertial calendar read +36, +37...
"Ghosts, eh?" Svetz's beefy, red faced boss scowled ferociously. At least he was taking it seriously. He might as easily have sent Svetz off for a psychiatric examination. "That's all we need. A haunted time machine. Well, have you got any idea what really happened?"
"There must be something wrong with the time machine. I think we ought to give up using it until we find out what."
"You do."
"Yes sir."
"Come here a minute." Ra Chen took Svetz's arm and walked away with him. He was twice Svetz's mass; his hand wrapped one and a half times around Svetz's bicep.
He stopped them before the picture window that fronted the Institute for Temporal Research.
Spread below them, the shops and houses and crooked streets of the city of Capitol. On the hill across the valley, tremendous and daunting, the complex of buildings that was the United Nations Palace.
Ra Chen pointed downhill. "There."
There was a gap in the cityscape. A cluster of broken houses surrounded the broken corpse of a bird, a bird the size of a five story building. It had been there for two weeks now. The stink reached them even here.
"Our worst failure to date. I forebear to point out to you, Svetz, that it was your idea to use regression treatments on an ostrich. Notice, however, that the futzy thing lies in full view of the Palace. We'll have to do something spectacular before the Advisors forget that gaff! And we'd better do it soon."
"Yes sir."
"We're in bad odor at the Palace, Svetz."
"Sir, I think that's the roc."
Ra Chen glared.
"We're already missing one time machine," he continued. "I had to yank it after we found out it was veering sidewise in time, across probability lines. The technical arm is still trying to find something wrong with it. Now you want me to yank the other one. Svetz, could you have imagined this-manifestation?"
"I've asked myself that."
"Well?"
"No, sir. It was real. Even if I could see through it."
"It's just such a lousy time to lose both time machines. Appropriations come up in three months."
The vets were removing his armadillo from the extension cage. Svetz watched them erect a gauzy filter tent over it to protect it from the air of 1102 Post Atomic.
"We ought to give up on funny animals," said Ra Chen. "The Secretary-General already has more extinct animals than he knows what to do with. We ought to try something else."
"Yes, sir. But what?"
Ra Chen didn't answer. They watched as the medical team took clone samples from the armadillo, then moved away with it. It was awake, but doing very little to prove it. Tomorrow it would be in the Vivarium.
"This ghost, now," Ra Chen said suddenly. "Was it human, or just humanoid?"
"It-there was something wrong with the face. Something dreadful."
"But was it a man or an alien?"
"I couldn't tell. After all, it was thin as smoke! It was wearing a robe. I couldn't see anything but the face and hands-and they were dreadfully thin. It looked like a walking skeleton."
"A skeleton, huh? Maybe you were seeing through the flesh. Like a holo of a man in X-ray light."
"That sounds right."
"But why? Why would he be transparent?"
"Funny, I was just wondering the same thing."
"Don't be sarcastic, Svetz."
"Sorry, sir."
"We've both been assuming it was a sign of something wrong with the time machine. What if it wasn't? What if the thing was real?"
Svetz shook his head violently. "There are no such things as ghosts."
"We thought that about roes. Why not? Think how long the ghost legend has been around. All over the world, in burial customs, folk tales, all the great religions. There are people who believe in ghosts even today. Not many, I admit-"
"But, sir, it's nonsense! Even if there were real ghosts, whatever they are, how would they get aboard an extension cage? And what could we do about it?"
"Capture it, of course. The Secretary-General would love it. He could even play with it; it sounded harmless enough-"
"But!"
"-Just ugly. As for how it got there, how should I know? I don't know anything about the theory of time travel. It should be' possible to duplicate the conditions-"
"You say it's harmless. I saw it. I say it isn't!"
"We can look into that after we've got it. Svetz, we need a coup. We're going after that ghost."
"We? Me! And I won't!"
"Come," said Ra Chen. "Let us reason together."
Gravity behaved oddly in an extension cage. Going backward in time, the pull was inward, toward Svetz's navel. Its intensity fluctuated to no known laws.
"I must be getting used to this," Svetz thought.
He found that ominous. Svetz hated time travel. If he was getting used to the odd motion, he had probably given up hope of changing careers.
At least he didn't get sick any more.
"How did he talk me into this?"
The extension cage slowed. Gravity dwindled, was gone, came back pointing down.
The inertial calendar read -704. 704 Ante Atomic, seven hundred years before the first nuclear explosion. Through the transparent hull of the extension cage Svetz could see a thousand shades of dark green, green in all directions: a place of obscenely proliferating life. It was the South American jungle where he had found the armadillo.
Svetz donned a filter sac and waited for it to inflate around his head. Then he cut the air system and opened the vents to flood the extension cage with outside air. The ghost had first appeared around 20 PA. If there was a ghost, and if it came, it would probably suffocate in industrial age air.
Svetz took a sonic stun gun from its place on the wall. Subsonics were less material than anaesthetic crystals, more likely to affect a ghost, he told himself.
He pulled the Go-Home lever.
And that was that. Svetz had no controls, only signals. The controls were in the future, with the bulk of the time machine in the Institute building. Now the technicians began bringing him home. They had readings from his last mission. They could make his cage behave as it had then.
Svetz had nothing to do but wait.
Time travel still cost over a million commercials a shot. If the cage simply brought him home now, he was going to feel like an idiot. But then, so would Ra Chen.
He was passing 17 Post Atomic when the haze began to form. Svetz stayed on his back, but he raised the handgun.
It was clearer now, more solid. A dark, voluminous cloak and hood showed behind the pale, translucent outline of a human skeleton. Details were blurred, mercifully perhaps, because the thing was moving too fast, screaming and pleading and gesticulating, all without a sound. It was frantic. It begged Svetz to stop the machine.
Svetz fired the stun weapon.
He kept the stud down until his own head buzzed from the echoes. The apparition screamed what must have been a string of curses, and thereafter ignored him. It wrapped the bones of its hands around the Emergency Stop, braced the bones of its feet against the control panel, and pulled.
The lever didn't move. It was as if fog clung to the control panel.
+46, +47, +48...
Svetz began to relax. The thing was harmless.
He was willing to believe that it was man-shaped, though he could see no trace of the ghostly flesh that mu
st surround the smoky bones. Perhaps he was watching some kind of probability phenomenon. As if the ghost-figure marked where a man might be if there were another man aboard Svetz's extension cage, and its transparency was a measure of just how improbable that was. . . Svetz's head began to ache. Certainly he could not be expected to capture a probability-phenomenon.
The ghost slowly faded, then became clear. It shifted its grip. The white of bones gleamed faintly through dark cloak.
+132,+133,'+134...
The ghost came solid in an instant. It pulled the Emergency Stop down hard, turned and leapt.
It was still a skeleton.
Svetz screamed high and shrill, turned and tried to burrow into the hull. He felt the thing land on his back, light and dry and hard. He wailed again. He was in fetal position now, hugging his knees. Bony fingers tugged at his hand, and he screamed and let go of the stun gun. The fingers took it away.
For a long time nothing happened. Svetz waited for the end. Instead he heard slow footsteps, clickings...
And a hollow, grating voice that said, "All right, that's enough of that. Roll over."
Small bones prodded Svetz's ribs. He rolled over and opened his eyes.
It was as bad as he'd thought. Worse. The ghost-figure had turned solid, but it was still no more than a mobile skeleton. It stood now with its cloak flung back and a sonic stun gun in its finger bones. Its face was a skull. Far back in the black eye sockets, eyes watched him steadily.
"Stop staring," said the apparition.
It spoke Speech. It spoke Svetz's language. But the consonants came out mushy, because the thing's skull was lipless.
It chuckled hollowly. "You can see me, can't you? It means you're going to die. When people can see me, it's because they're going to die."
"No," Svetz whispered. His legs were trying to push him back through the wall of the extension cage.
"Stop staring! It's not my fault I'm this way. It was the radiation." The apparition shifted uncomfortably. "What's your name?"
"S-svetz."
"Allow me to introduce myself. I am Doctor Nathaniel Reynolds, the world's first time traveler, and I've decided to hijack your time machine."
Svetz licked his lips. "I don't think so. The first time traveler-"
"I beat him to it. On another line of history, of course. A dead line. My own fault. Have you ever heard of the Cuban missile crisis? The date was nineteen fifty-eight AD, Seventeen Post Atomic, your dating."
"No."
"You're sure? We called it the Short War."
Svetz shook his head.
"Doctor Reynolds" settled himself against the curved wall. He held Svetz's gun steadily on Svetz.
He was not as much a skeleton as Svetz had thought. There was skin over the bones, though the skin itself was the white of bleached bone. In Reynolds's neck there were trachea and gullet as well as the lumpy row of vertebrae.
The rib cage was something else again. Reynolds's ribs were naked bone. Behind the ribs was a narrow torso of flabby white flesh that pulsed like lungs. Torso and abdomen depended from the spine; but daylight showed between the exoskeletal ribs.
The nose and ears were mere holes.
The pelvic bones were sharp as ax blades.
Doctor Reynolds was both hairless and sexless.
He said, "I don't talk well. The only people who can see me and hear me are always about to die. Sometimes they're too sick to concentrate. Sometimes too busy. Sometimes too scared."
"Am I dying?"
Reynolds chuckled. "We'll decide that between us."
"What are you?"
"I'm a ghost. My own fault. But don't laugh. It could happen to you."
Svetz was not thinking of laughing.
"Let me tell you. I was born about a century after the Short War," said Doctor Reynolds. "By then it was obvious the human race was dying. Too many countries had dropped too many bombs in the Short War. Some were cobalt bombs. There was still too much radiation around.
Too many mutations, mostly sick and mostly sterile, not to mention disgusting. I was one of the lucky ones."
Svetz said nothing.
"I'd have knocked your teeth out," said the hollow voice. "I really was one of the lucky ones. No brain damage. No gonads, but so what? With all the radiation around I wouldn't have bred true anyway. No organic damage that couldn't be fixed by available medicines. I had to take the pills every day, of course. Would you believe that I once had a pot belly?"
Svetz shook his head.
"A very small pot belly. I had to get rid of it. It hurt. My abdominal muscles couldn't carry the weight. Funny: I've never picked up fat anywhere else. Just the belly, and bones showing through the rest of me."
"How did you get to be a ghost?"
Reynolds laughed, a weak, hollow sound. "Deliberately, and by dint of great effort. There were thousands of us working on it. There wasn't any question that we were doomed. Our best brains, such as we were, were working on time travel. We called it Project Retake. You know what a retake is?"
"Doing a scene over for a sensory."
"That's what we were after. We weren't sure the past could be changed even if we did have time travel. But we had to try it. We did it, too. The time machine was just big enough for me and the scrambler system. They picked me because I only weigh about fifty pounds."
"What did you do?"
"Scrambled the guidance mechanisms of every guided missile in the Union of Soviet Socialist Republics, a week before the Cuban missile crisis. They had to back down and move the missiles out of Cuba. By the time they got their missiles fixed the crisis was over, and they still didn't know what had happened. It must have made them cautious for awhile afterward.
"I monitored it all by radio. I made sure nobody saw me, of course. My appearance is a bit-"
"Right."
"So. Afterward I tried to go home. Not to my own present, but to the new one, the one I'd created. My time machine didn't work. We saved a lot of weight by leaving the power source fixed in the future. Now it was gone.
"I left the time machine and went to give myself up. And found out I was gone too...
"Well, that's all over now," said Reynolds. He hefted the stunner. The bones of his hands were crossed by narrow strands of muscle. His fingernails were long and ragged. "We're going to put it back the way it was."
"Uh?"
"Using your time machine. Mine wouldn't do it, but yours will. We're going back to seventeen Post Atomic."
"We can't."
"I'll kill you if we don't."
Sventz believed him. When Nathaniel Reynolds gave himself a name, Svetz had stopped seeing him as a supernatural horror. But he was convinced that the bony physicist was mad.
He said, "You don't understand. This isn't a time machine, It's only the extension cage, the part that does the moving. The technicians have to haul me back to the present before they can send me back again."
"You're lying."
"No! Reynolds, there aren't any controls here-just on-off pulses to tell the technicians which way to move me. They can only move me forward now."
"I almost believe you," Reynolds mused. "But I'll still kill you unless one of us thinks of something."
"You're crazy! You'd have to be crazy to want your bombed-out world back!"
The skeleton clacked his teeth. Svetz saw the red of his mouth, horribly incongruous in the white skull. "Svelz, you haven't asked me how long I've been a ghost."
"How long, then?'
"There's no way to measure. Svetz, I'm anchored to seventeen Post Atomic. I wait, I get eight months or so beyond the Cuban missile crisis, and then everything slows down and stops. I think it's been thousands of years. More.
"Can you imagine anything more horrible? It's a frozen world. People like statues. Pigeons nailed to the air. I'm frozen too. I don't get old, I don't get hungry. Sunlight goes right through me. See how white my skin is? And I can't die. I'm not real enough to die. I'd have gone crazy long ago if it we
ren't for the time machines."
Reynolds's eyes burned black within the pits of his skull. "The time machines. I see them going and coming, Svetz. Some from your line of history, some from others. Yours is the real future, the future I made. But I can ride the others too.
"Mostly I ride them into the past as far as they'll go.
That way time passes normally for me, until seventeen Post Atomic rolls around again. I've been through the Middle Ages a dozen times.
"Funny thing, Svetz. I'm invisible to most people. But anyone can see me if he's about to die. Maybe because he's about to leave time entirely; it doesn't matter what line of history he's on, or I'm on." Reynolds laughed. "I think some of them die because they see me. Heart failure."
Svetz shuddered. Reynolds was probably right.
Reynolds said, "Not funny, eh? I've been in the future too. Dozens of futures. Svetz, did you know that your time machines go sidewise in time?"
"We had one that did. It was damaged."
"They all do. They wobble. The self-powered ones get lost. The ones that are anchored to their own lines of history, like yours, they always get pulled back, no matter how far they slip across alternate probabilities.
"I've seen some strange futures, Svetz. Paradises. Alien invasions. One where elephants were civilized. I've been in your future," Reynolds said bitterly. "Long enough to learn Speech. Long enough to see what you've done to the world I made you."
"What do you mean?"
'What do I mean? Everything's dirty, everything's dead! You killed off everything but yourselves and that gray sludge you eat-"
"Dole yeast."
"Dole yeast. I know a short word that would fit it better. I've watched you ejecting that sludge from your mouths-"
"What?"
"I was going backward in time, of course, waiting to slide back to seventeen Post Atomic. The fun goes out of that awfully fast. I don't like hopping time machines into the future, not unless I can get a ride back.
"But I do it anyway. There's always the chance a time machine will wobble across my own line of history. Then I could get off, or even stop the machine. And it paid off, didn't it?"
"I don't understand."
"You haven't looked outside at all, have you, Svetz?"
