Harlan said, "What if I don't find it?"

"You will. Eternity exists, doesn't it. As long as it does, we're on the right track. Tell me, can you recall such an advertis.e.m.e.nt in your work with Cooper? Anything which struck you, even momentarily, as odd, queer, unusual, subtly wrong."

"No."

"I don't want an answer so quickly. Take five minutes and think."

"No point. At the time I was going over the news magazines with Cooper, he hadn't been in the 20th."

"Please, boy. Use your head. Sending Cooper to the 20th has introduced an alteration. There's no Change; it isn't an irreversible alteration. But there have been some changes with a small 'c,' or micro-changes, as it is usually referred to in Computation. At the instant Cooper was sent to the 20th, the advertis.e.m.e.nt appeared in the appropriate issue of the magazine. Your own Reality has micro-changed in the sense that you may have looked at the page with that advertis.e.m.e.nt on it rather than one without that advertis.e.m.e.nt as you did in the previous Reality. Do you understand?"

Harlan was again bewildered, almost as much at the ease with which Twissell picked his way through the jungle of temporal logic, as at the "paradoxes" of Time. He shook his head, "I remember nothing of the sort."

"Well, then, where do you keep the files of that periodical?"

"I had a special library built on Level Two, using the Cooper priority."

"Good enough," said Twissell. "Let's go there. Now!"

Harlan watched Twissell stare curiously at the old, bound volumes in the library and then take one down. They were so old that the fragile paper had to be preserved by special methods and they creaked under Twissell's insufficiently gentle handling.

Harlan winced. In better times he would have ordered Twissell away from the books, Senior Computer though he was.

The old man peered through the crinkling pages and silently mouthed the archaic words. "This is the English the linguists are always talking about, isn't it?" he asked, tapping a page.

"Yes. English," muttered Harlan.

Twissell put the volume back. "Heavy and clumsy."

Harlan shrugged. To be sure, most of the Centuries of Eternity were film eras. A respectable minority were molecular-recording eras. Still, print and paper were not unheard of.

He said, "Books don't require the investment in technology that films do."

Twissell rubbed his chin. "Quite. Shall we get started?"

He took another volume down from the shelf, opening it at random and staring at the page with odd intentness.

Harlan thought: Does the man think he's going to hit the solution by a lucky stab?

The thought might have been correct, for Twissell, meeting Harlan's appraising eyes, reddened and put the book back.

Harlan took the first volume of the 19.25th Centicentury and began turning the pages regularly. Only his right hand and his eyes moved. The rest of his body remained at rigid attention.

At what seemed aeonic intervals to himself Harlan rose, grunting, for a new volume. On those occasions there would be the coffee break or the sandwich break or the other breaks.

Harlan said heavily, "It's useless your staying."

Twissell said, "Do I bother you?"

"No."

"Then I'll stay," muttered Twissell. Throughout he wandered occasionally to the bookshelves, staring helplessly at the bindings. The sparks of his furious cigarettes burned his finger ends at times, but he disregarded them.

A physioday ended.

Sleep was poor and spa.r.s.e. Midmorning, between two volumes, Twissell lingered over his last sip of coffee and said, "I wonder sometimes why I didn't throw up my Computership after the matter of my---- You know."

Harlan nodded.

"I felt like it," the old man went on. "I felt like it. For physiomonths, I hoped desperately that no Changes would come my way. I got morbid about it. I began to wonder if Changes were right. Funny, the tricks emotions will play on you.

"_You_ know Primitive history, Harlan. You know what it was like. Its Reality flowed blindly along the line of maximum probability. If that maximum probability involved a pandemic, or ten Centuries of slave economy, a breakdown of technology, or even a--a--let's see, what's really bad--even an atomic war if one had been possible then, why, by Time, it _happened_. There was nothing to stop it.

"But where Eternity exists, that's been stopped. Upwhen from the 28th, things like that don't happen. Father Time, we've lifted our Reality to a level of well-being far beyond anything Primitive times could imagine; to a level which, but for the interference of Eternity, would have been very low probability indeed."

Harlan thought in shame: What's he trying to do? Get me to work harder? I'm doing my best.

Twissell said, "If we miss our chance now, Eternity disappears, probably through all of physiotime. And in one vast Change all Reality reverts to maximum probability with, I am positive, atomic warfare and the end of man."

Harlan said, "I'd better get on to the next volume."

At the next break Twissell said helplessly, "There's so much to do. Isn't there a faster way?"

Harlan said, "Name it. To me it seems that I must look at every single page. And look at every part of it, too. How can I do it faster?"

Methodically he turned the pages.

"Eventually," said Harlan, "the print starts blurring and that means it's time for sleep."

A second physioday ended.

At 10:22 A.M., Standard Physiotime, of the third physioday of the search Harlan stared at a page in quiet wonder and said, "This is it!"

Twissell didn't absorb the statement. He said, "What?"

Harlan looked up, his face twisted with astonishment. "You know, I didn't believe it. By Time, I never really believed it, even while you were working out all that rigmarole about news magazines and advertis.e.m.e.nts."

Twissell had absorbed it now. "_You've found it!_"

He leaped at the volume Harlan was holding, clutching at it with shaking fingers.

Harlan held it out of reach and slammed the volume shut. "Just a moment. _You_ won't find it, even if I showed you the page."

"What are you doing?" shrieked Twissell. "You've lost it."

"It's not lost. I know where it is. But first----"

"First what?"

Harlan said, "There's one point remaining, Computer Twissell. You say I can have Noys. Bring her to me, then. Let me see her."

Twissell stared at Harlan, his thin white hair in disarray. "Are you joking?"

"No," said Harlan sharply, "I'm not joking. You a.s.sured me that you would make arrangments-- Are _you_ joking? Noys and I would be together. You promised that."

"Yes, I did. That part's settled."

"Then produce her alive, well, and untouched."

"But I don't understand you. I don't have her. No one has. She's still in the far upwhen, where Finge reported her to be. No one has touched her. Great Time, I told you she was safe."

Harlan stared at the old man and grew tense. He said, chokingly, "You're playing with words. All right, she's in the far upwhen, but what good is that to me? Take down the barrier at the 100,000th--"

"The what?"

"The barrier. The kettle won't pa.s.s it."

"You never said anything of this," said Twissell wildly.

"I haven't?" said Harlan with sharp surprise. Hadn't he? He had thought of it often enough. Had he never said a word about it? He couldn't recall, at that. But then he hardened.

He said, "All right. I tell you now. Take it down."

"But the thing is impossible. A barrier against the kettle? A temporal barrier?"

"Are you telling me you didn't put one up?"

"I didn't. By Time, I swear it."

"Then--then----" Harlan felt himself grow pale. "Then the Council did it. They know of all this and they've taken action independently of you and--and by all of Time and Reality, they can whistle for their ad and for Cooper, for Mallansohn and all of Eternity. They'll have none of it. None of it."

"Wait. Wait." Twissell yanked despairingly at Harlan's elbow. "Keep hold of yourself. Think, boy, think. The Council put up no barrier."

"It's there."

"But they can't have put up such a barrier. No one could have. It's theoretically impossible."

"You don't know it all. It's there."

"I know more than anyone else on the Council and such a thing is impossible."

"But it's there."

"But if it is----"

And Harlan grew sufficiently aware of his surroundings to realize that there was a kind of abject fear in Twissell's eyes; a fear that had not been there even when he first learned of Cooper's misdirection and of the impending end of Eternity.

16 The Hidden Centuries

Andrew Harlan watched the men at work with abstracted eyes. They ignored him politely because he was a Technician. Ordinarily he would have ignored them somewhat less politely because they were Maintenance men. But now he watched them and, in his misery, he even caught himself envying them.

They were service personnel from the Department of Intertemporal Transportation, in dun-gray uniforms with shoulder patches showing a red, double-headed arrow against a black background. They used intricate force-field equipment to test the kettle motors and the degrees of hyper-freedom along the kettleways. They had, Harlan imagined, little theoretical knowledge of temporal engineering, but it was obvious that they had a vast practical knowledge of the subject.

Harlan had not learned much concerning Maintenance when he was a Cub. Or, to put it more accurately, he had not really wished to learn. Cubs who did not make the grade were put into Maintenance. The "unspecialized profession" (as the euphemism had it) was the hallmark of failure and the average Cub automatically avoided the subject.

Yet now, as he watched the Maintenance men at work, they seemed to Harlan to be quietly, tensionlessly efficient, reasonably happy.

Why not? They outnumbered the Specialists, the "true Eternals," ten to one. They had a society of their own, residential levels devoted to them, pleasures of their own. Their labor was fixed at so many hours per physioday and there was no social pressure in their case to make them relate their spare-time activity to their profession. They had time, as Specialists did not, to devote to the literature and film dramatizations culled out of the various Realities.

It was they, after all, who probably had the better-rounded personalities. It was the Specialist's life which was harried and affected, artificial in comparison with the sweet and simple life in Maintenance.

Maintenance was the foundation of Eternity. Strange that such an obvious fact had not struck him earlier. They supervised the importation of food and water from Time, the disposal of waste, the functioning of the power plants. They kept all the machinery of Eternity running smoothly. If every Specialist were to die of a stroke on the spot, Maintenance could keep Eternity going indefinitely. Yet were Maintenance to disappear, the Specialists would have to abandon Eternity in days or die miserably.

Did Maintenance men resent the loss of their homewhens, or their womanless, childless lives? Was security from poverty, disease, and Reality Change sufficient compensation? Were their views ever consuited on any matter of importance? Harlan felt some of the fire of the social reformer within him.

Senior Computer Twissell broke Harlan's train of thought by bustling in at a half run, looking even more haunted than he had an hour before, when he had left, with Maintenance already at work.

Harlan thought: How does he keep it up? He's an old man.

Twissell glanced about him with birdlike brightness as the men automatically straightened up to respectful attention.

He said, "What about the kettleways?"

One of the men responded, "Nothing wrong, sir. The ways are clear, the fields mesh."

"You've checked everything?"

"Yes, sir. As far upwhen as the Department's stations go."

Twissell said, "Then go."

There was no mistaking the brusque insistence of his dismissal. They bowed respectfully, turned, and hastened out briskly.

Twissell and Harlan were alone in the kettleways.

Twissell turned to him. "You'll stay here. Please."

Harlan shook his head. "I must go."

Twissell said, "Surely you understand. If anything happens to me, you still know how to find Cooper. If anything happens to you, what can I or any Eternal or any combination of Eternals do alone?"

Harlan shook his head again.