It was, looking back at it, an idyllic period that followed. A hundred things took place in those physioweeks, and all confused itself inextricably in Harlan's memory, later, making the period seem to have lasted much longer than it did. The one idyllic thing about it was, of course, the hours he could spend with Noys, and that cast a glow over everything else.

Item One: At the 482nd he slowly packed his personal effects; his clothing and films, most of all his beloved and tenderly handled newsmagazine volumes out of the Primitive. Anxiously he supervised their return to his permanent station in the 575th.

Finge was at his elbow as the last of it was lifted into the freight kettle by Maintenance men.

Finge said, choosing his words with unerring triteness, "Leaving us, I see." His smile was broad, but his lips were carefully held together so that only the barest trace of teeth showed. He kept his hands clasped behind his back and his pudgy body teetered forward on the balls of his feet.

Harlan did not look at his superior. He muttered a monotoned "Yes, sir."

Finge said, "I will report to Senior Computer Twissell concerning the entirely satisfactory manner in which you performed your Observational duties in the 482nd."

Harlan could not bring himself to utter even a sullen word of thanks. He remained silent.

Finge went on, in a suddenly much lower voice, "I will not report, for the present, your recent attempt at violence against me." And although his smile remained and his glance remained mild, there was a relish of cruel satisfaction about him.

Harlan looked up sharply and said, "As you wish, Computer."

Item Two: He re-established himself at the 575th.

He met Twissell almost at once. He found himself happy to see that little body, topped by that lined and gnomelike face. He was even happy to see the white cylinder nestling smokily between two stained fingers and being lifted rapidly toward Twissell's lips.

Harlan said, "Computer."

Twissell, emerging from his office, looked for a moment unseeingly and unrecognizingly at Harlan. His face was haggard and his eyes squinted with weariness.

He said, "Ah, Technician Harlan. You are done with your work in the 482nd?"

"Yes, sir."

Twissell's comment was strange. He looked at his watch, which, like any watch in Eternity, was geared to physiotime, giving the day number as well as the time of day, and said, "On the nose, my boy, on the nose. Wonderful. Wonderful."

Harlan felt his heart give a small bound. When he had last seen Twissell he would not have been able to make sense of that remark. Now he thought he did. Twissell was tired, or he would not have spoken so close to the core of things, perhaps. Or the Computer might have felt the remark to be so cryptic as to feel safe despite its closeness to the core.

Harlan said, speaking ascasually as he could to avoid letting it seem that his remark had any connection at all with what Twissell had just said, "How's my Cub?"

"Fine, fine," said Twissell, with only half his mind, apparently, on his words. He took a quick puff at the shortening tube of tobacco, indulged in a quick nod of dismissal, and hurried off.

Item Three: the Cub.

He seemed older. There seemed to be a greater feeling of maturity to him as he held out his hand and said, "Glad to see you back, Harlan."

Or was it merely that, where earlier Harlan had been conscious of Cooper only as a pupil, he now seemed more than a Cub. He now seemed a gigantic instrument in the hands of the Eternals. Naturally he could not help but attain a new stature in Harlan's eyes.

Harlan tried not to show that. They were in Harlan's own quarters, and the Technician basked in the creamy porcelain surfaces about him, glad to be out of the ornate splash of the 482nd. Try as he might to associate the wild baroque of the 482nd with Noys, he only succeeded in associating it with Finge. With Noys he associated a pink, satiny twilight and, strangely, the bare austerity of the Sections of the Hidden Centuries.

He spoke hastily, almost as though he were anxious to hide his dangerous thoughts. "Well, Cooper, what have they been doing with you while I was away?"

Cooper laughed, brushed his drooping mustache self-consciously with one finger and said, "More math. Always math."

"Yes? Pretty advanced stuff by now, I guess."

"Pretty advanced."

"How's it coming?"

"So far it's bearable. It comes pretty easy, you know. I like it. But now they're really loading it on."

Harlan nodded and felt a certain satisfaction. He said, "Temporal Field matrices and all that?"

But Cooper, his color a little high, turned toward the stacked volumes in the bookshelves, and said, "Let's get back to the Primitives. I've got some questions."

"About what?"

"City life in the 23rd. Los Angeles, especially."

"Why Los Angeles?"

"It's an interesting city. Don't you think so?"

"It is, but let's hit it in the 21st, then. It was at its peak in the 21st."

"Oh, let's try the 23rd."

Harlan said, "Well, why not?"

His face was impassive, but if the impassiveness could have been peeled off, there would have been a grimness about him. His grand, intuitional guess was more than a guess. Everything was checking neatly.

Item Four: research. Twofold research.

For himself, first. Each day, with ferreting eyes, he went through the reports on Twissell's desk. The reports concerned the various Reality Changes being scheduled or suggested. Copies went to Twissell routinely since he was a member of the Allwhen Council, and Harlan knew he would not miss one. He looked first for the coming Change in the 482nd. Secondly he looked for other Changes, any other Changes, that might have a flaw, an imperfection, some deviation from maximum excellence that might be visible to his own trained and talented Technician's eyes.

In the strictest sense of the word the reports were not for his study, but Twissell was rarely in his office these days, and no one else saw fit to interfere with Twissell's personal Technician.

That was one part of his research. The other took place in the 575th Section branch of the library.

For the first time he ventured out of those portions of the library which, ordinarily, monopolized his attention. In the past he had haunted the section on Primitive history (very poor indeed, so that most of his references and source materials had to be derived from the far downwhen of the 3rd millennium, as was only natural, of course). To an even greater extent he had ransacked the shelves devoted to Reality Change, its theory, technique, and history; an excellent collection (best in Eternity outside the Central branch itself, thanks to Twissell) of which he had made himself full master.

Now he wandered curiously among the other film-racks. For the first time he Observed (in the capital-O sense) the racks devoted to the 575th itself; its geographies, which varied little from Reality to Reality, its histories, which varied more, and its sociologies, which varied still more. These were not the books or reports written about the Century by Observing and Computing Eternals (with those he was familiar), but by the Timers themselves.

There were the works of literature of the 575th and these stirred memories of tremendous arguments he had heard of concerning the values of alternate Changes. Would this masterpiece be altered or not? If so, how? How did past Changes affect works of art?

For that matter, could there ever be general agreement about art? Could it ever be reduced to quantitative terms amenable to mechanical evaluation by the Computing machines?

A Computer named August Sennor was Twissell's chief opponent in these matters. Harlan, stirred by Twissell's feverish denunciations of the man and his views, had read some of Sennor's papers and found them startling.

Sennor asked publicly and, to Harlan, disconcertingly, whether a new Reality might not contain a personality within itself analogous to that of a man who had been withdrawn into Eternity in a previous Reality. He analyzed then the possibility of an Eternal meeting his analogue in Time, either with or without knowing it, and speculated on the results in each case. (That came fairly close to one of Eternity's most potent fears, and Harlan shivered and hastened uneasily through the discussion.) And, of course, he discussed at length the fate of literature and art in various types and classifications of Reality Changes.

But Twissell would have none of the last. "If the values of art can't be computed," he would shout at Harlan, "then what's the use of arguing about it?"

And Twissell's views, Harlan knew, were shared by the large majority of the Allwhen Council.

Yet now Harlan stood at the shelves devoted to the novels of Eric Linkollew, usually described as the outstanding writer of the 575th, and wondered. He counted fifteen different "Complete Works" collections, each, undoubtedly, taken out of a different Reality. Each was somewhat different, he was sure. One set was noticeably smaller than all the others, for instance. A hundred Sociologists, he imagined, must have written analyses of the differences between the sets in terms of the sociological background of each Reality, and earned status thereby.

Harlan passed on to the wing of the library which was devoted to the devices and instrumentation of the various 575th's. Many of these last, Harlan knew, had been eliminated in Time and remained intact, as a product of human ingenuity, only in Eternity. Man had to be protected from his own too flourishing technical mind. That more than anything else. Not a physioyear passed but that somewhere in Time nuclear technology veered too close to the dangerous and had to be steered away.

He returned to the library proper and to the shelves on mathematics and mathematical histories. His fingers skimmed across individual titles, and after some thought he took half a dozen from the shelves and signed them out.

Item Five: Noys.

That was the really important part of the interlude, and all the idyllic part.

In his off-hours, when Cooper was gone, when he might ordinarily have been eating in solitude, reading in solitude, sleeping in solitude, waiting in solitude for the next day-he took to the kettles.

With all his heart he was grateful for the Technician's position in society. He was thankful, as he had never dreamed he could be, for the manner in which he was avoided.

No one questioned his right to be in a kettle, nor cared whether he aimed it upwhen or down. No curious eyes followed him, no willing hands offered to help him, no chattering mouths discussed it with him.

He could go where and when he pleased.

Noys said, "You've changed, Andrew. Heavens, you've changed."

He looked at her and smiled. "In what way, Noys?"

"You're smiling, aren't you? That's one of the ways. Don't you ever look in a mirror and see yourself smiling?"

"I'm afraid to. I'd say: 'I can't be that happy. I'm sick. I'm delirious. I'm confined in an asylum, living in daydreams, and unaware of it.'"

Noys leaned close to pinch him. "Feel anything?"

He drew her head toward him, felt bathed in her soft, black hair.

When they separated, she said breathlessly, "You've changed there, too. You've become very good at it."

"I've got a good teacher," began Harlan, and stopped abruptly, fearing that would imply displeasure at the thought of the many who might have had the making of such a good teacher.

But her laugh seemed untroubled by such a thought. They had eaten and she looked silky-smooth and warmly soft in the clothing he had brought her.

She followed his eyes and fingered the skirt gently, lifting it loose from its soft embrace of her thigh. She said, "I wish you wouldn't, Andrew. I really wish you wouldn't."

"There's no danger," he said carelessly.

"There is danger. Now don't be foolish. I can get along with what's here, until-until you make arrangements."

"Why shouldn't you have your own clothes and doodads?"

"Because they're not worth your going to my house in Time and being caught. And what if they make the Change while you're there?"

He evaded that uneasily. "It won't catch me." Then, brightening, "Besides my wrist generator keeps me in physiotime so that a Change can't affect me, you see."

Noys sighed. "I don't see. I don't think I'll ever understand it all."

"There's nothing to it." And Harlan explained and explained with great animation and Noys listened with sparkling eyes that never quite revealed whether she was entirely interested, or amused, or, perhaps, a little of both.

It was a great addition to Harlan's life. There was someone to talk to, someone with whom to discuss his life, his deeds, and thoughts. It was as though she were a portion of himself, but a portion sufficiently separate to require speech in communication rather than thought. She was a portion sufficiently separate to be able to answer unpredictably out of independent thought processes. Strange, Harlan thought, how one might Observe a social phenomenon such as matrimony and yet miss so vital a truth about it. Could he have predicted in advance, for instance, that it would be the passionate interludes that he would later least often associate with the idyl?

She snuggled into the crook of his arm and said, "How is your mathematics coming along?"

Harlan said, "Want to look at a piece of it?"

"Don't tell me you carry it around with you?"

"Why not? The kettle trip takes time. No use wasting it, you know."

He disengaged himself, took a small viewer from his pocket, inserted the film, and smiled fondly as she put it to her eyes.

She returned the viewer to him with a shake of her head. "I never saw so many squiggles. I wish I could read your Standard Intertemporal."

"Actually," said Harlan, "most of the squiggles you mention aren't Intertemporal really, just mathematical notation."

"You understand it, though, don't you?"

Harlan hated to do anything to disillusion the frank admiration in her eyes, but he was forced to say, "Not as much as I'd like to. Still, I have been picking up enough math to get what I want. I don't have to understand everything to be able to see a hole in a wall big enough to push a freight kettle through."

He tossed the viewer into the air, caught it with a flick of his hand, and put it on a small end-table.

Noys's eyes followed it hungrily and sudden insight flashed on Harlan.

He said, "Father Time! You can't read Intertemporal, at that."

"No. Of course not."

"Then the Section library here is useless to you. I never thought of that. You ought to have your own films from the 482nd."

She said quickly, "No. I don't want any."

He said, "You'll have them."

"Honestly, I don't want them. It's silly to risk--"

"You'll have them!" he said.

For the last time he stood at the immaterial boundary separating Eternity from Noys's house in the 482nd. He had intended the time before to be the last time. The Change was nearly upon them now, a fact he had not told Noys out of the decent respect he would have had for anyone's feelings, let alone those of his love.

Yet it wasn't a difficult decision to make, this one additional trip. Partly it was bravado, to shine before Noys, bring her the book-films from out the lion's mouth; partly it was a hot desire (what was the Primitive phrase?) "to singe the beard of the King of Spain," if he might refer to the smooth-checked Finge so.

Then, too, he would have the chance once again of savoring the weirdly attractive atmosphere about a doomed house.

He had felt it before, when entering it carefully during the period of grace allowed by the spatio-temporal charts. He had felt it as he wandered through its rooms, collecting clothing, small _objets d'art_, strange containers, and instruments from Noys's vanity table.

There was the somber silence of a doomed Reality that was past merely the physical absence of noise. There was no way for Harlan to predict its analogue in a new Reality. It might be a small suburban cottage or a tenement in a city street. It might be zero with untamed scrubland replacing the parklike terrain on which it now stood. It might, conceivably, be almost unchanged. And (Harlan touched on this thought gingerly) it might be inhabited by the analogue of Noys or, of course, it might not.

To Harlan the house was already a ghost, a premature specter that had begun its hauntings before it had actually died. And because the house, as it was, meant a great deal to him, he found he resented its passing and mourned it.

Once, only, in five trips had there been any sound to break the stillness during his prowlings. He was in the pantry, then, thankful that the technology of that Reality and Century had made servants unfashionable and removed a problem. He had, he recalled, chosen among the cans of prepared foods, and was just deciding that he had enough for one trip, and that Noys would be pleased indeed to intersperse the hearty but uncolorful basic diet provided in the empty Section with some of her own dietary. He even laughed aloud to think that not long before he had thought her diet decadent.

It was in the middle of the laugh that he heard a distinct clapping noise. He froze!

The sound had come from somewhere behind him, and in the startled moment during which he had not moved the lesser danger that it was a housebreaker occurred to him first and the greater danger of its being an investigating Eternal occurred second.

It couldn't be a housebreaker. The entire period of the spatio-temporal chart, grace period and all, had been painstakingly cleared and chosen out of other similar periods of Time because of the lack of complicating factors. On the other hand, he had introduced a micro-Change (perhaps not so micro at that) by abstracting Noys.

Heart pounding, he forced himself to turn. It seemed to him that the door behind him had just closed, moving the last millimeter required to bring it flush with the wall.

He repressed the impulse to open that door, to search the house. With Noys's delicacies in tow he returned to Eternity and waited two full days for repercussions before venturing into the far upwhen. There were none and eventually he forgot the incident.

But now, as he adjusted the controls to enter Time this one last time, he thought of it again. Or perhaps it was the thought of the Change, nearly upon him now, that preyed on him. Looking back on the moment later on, he felt that it was one or the other that caused him to misadjust the controls. He could think of no other excuse.

The misadjustment was not immediately apparent. It pin-pointed the proper room and Harlan stepped directly into Noys's library.

He had become enough of a decadent himself, now, to be not altogether repelled by the workmanship that went into the design of the film-cases. The lettering of the titles blended in with the intricate filigree until they were attractive but nearly unreadable. It was a triumph of aesthetics over utility.

Harlan took a few from the shelves at random and was surprised. The title of one was _Social and Economic History of our Times_.

Somehow it was a side of Noys to which he had given little thought. She was certainly not stupid and yet it never occurred to him that she might be interested in weighty things. He had the impulse to scan a bit of the _Social and Economic History_, but fought it down. He would find it in the Section library of the 482nd, if he ever wanted it. Finge had undoubtedly rifled the libraries of this Reality for Eternity's records months earlier.

He put that film to one side, ran through the rest, selected the fiction and some of what seemed light non-fiction. Those and two pocket viewers. He stowed them carefully into a knapsack.

It was at that point that, once more, he heard a sound in the house. There was no mistake this time. It was not a short sound of indeterminate origin. It was a langh, a man's laugh. He was not alone in the house.

He was unaware that he had dropped the knapsack. For one dizzy second he could think only that he was trapped!