She frowned as she watched him look around. She was annoyed by the fact that it took him almost a minute to get his bearings and realize that she was first, a human being and second, a girl well worth a man's attention.

Even the troubled expression in his eyes was something she held against him. A man shouldn't look troubled. A man should be confident, self-assured in a manner that also assured the girl he spoke to. She remembered that back on Earth John Burr had been completely self-assured.

It was startling to realize that it was with this newcomer, whose appearance she had every reason to dislike, that she had fallen suddenly and completely in love, as suddenly and completely as if she had fallen off a cliff.

"I'm looking for some people," he said. "But I suppose—" His very voice was ill at ease, and that was something else she should have held against him. And against herself. She had always resented men whose voices betrayed their lack of confidence. "I suppose it's no use," he went on. "I'd recognize the house."

"Who are the people you're looking for?"

He took out a wallet, and from it drew a stereo picture. Two children, a boy and a girl, were standing with a smiling young woman in front of a sturdy, old-fashioned plastic house. Their clothes were out of fashion by a year or so, but that depended on where you were. Mars, for instance, was always three years behind Earth. Here on Ganymede, on the other hand, you might even be ahead of Earth in some respects.

As Carol's eyes lifted to his, she saw him staring at the picture with such longing that she at once knew herself for a fool. They're his wife and children, she thought. He's trying to find them. And I had to fall in love with him at first sight.

His eyes were on her now, and she said, "I'm sorry, I've never seen them."

"Have you lived around here long?"

"Five years."

"Then this can't be the place." He stood there irresolutely and started to turn slowly away without even a word of thanks to her.

"My father may have heard about them," said Carol, knowing herself for a fool again.

Past experience, she told herself ruefully, had taught her nothing. The thing to do was to let him go and forget him as quickly as possible, before she learned anything about him, before her feeling for him could become anything more than an irrational, momentary impulse. The stronger the bonds of knowledge and interest between them, the more painful they would be to break. And the breaking was inevitable.

The house where she and her father lived was a simple dome-shaped building, its walls and furniture both made of a silicon plastic whose raw materials had come from the ground on which it stood. There were rugs and draperies of a slightly different composition, woven on the all-purpose Household Helper that her father had bought before leaving Earth. They lived comfortably enough, she thought, as she led the man in.

But he hardly noticed the house or anything in it. When they reached the library and her father looked up from the book he was reading, only then did the man display interest. The book was a favorite of her father's and it made him unhappy to cut his reading short.

Nevertheless, he turned off the projector, stood up, and said, "Yes, Carol?"

"This man is looking for some—some friends of his, Dad. I thought you might be able to help him."

She held out the picture and, to her relief, her father stared at that instead of at her. Sometimes he was a little too shrewd; if she was making a fool of herself, there was no need for him to know it. He could be a sardonic man and he did not suffer fools gladly, even in his own family. He was of the opinion that she had used up her quota of foolishness with John Burr.

He was shaking his head. "Sorry, I've never seen them. Are you sure they live around here?"

"No," said the man. "I'm not sure. I'm not sure of anything, except that they're my wife and kids. And I've got to find them."

"Have you checked at the District Office?"

"I did that first. They couldn't help me, but they said their records weren't complete yet."

"They're complete enough, I should think. Maybe they don't list every prospector who wanders around without settling down, but they wouldn't be likely to miss a woman and two children. I'm afraid that you're wasting your time looking on Ganymede."

The man's face clouded. "It isn't a waste of my time," he said. "I've got nothing else to do with it. And I have to find them. They need me."

Mr. Marsh looked away from the man to his daughter, and Carol was a little slow in avoiding his eyes. "I see," he said, and she had an idea of what he meant by that. He saw too much.

If he knew, there was nothing she could do about it. She said, "Perhaps Mr.—"

She paused, and the man said dully, "Callendar."

"Perhaps if Mr. Callendar would have dinner with us and tell us a little more, we'd be better able to help."

"Not a bad idea, Carol. We should know a little more."

Carol selected a dinner and pressed the button that would start its preparation.

Her father said casually, "You are a stranger to Ganymede, aren't you, Mr. Callendar?"

"I'm not sure of that," said the man.

Her father's eyebrows went up.

Carol said, "But you do come from one of Jupiter's moons?"

"I can't remember which one. There are a lot of things that my memory's hazy about. I can't even recall the name of the company I worked for as an engineer."

"That may not be so strange. I find difficulty remembering the school where I taught on Earth. P.S. 654, wasn't it, Dad?"

"P.S. 634," Mr. Marsh corrected briefly.

"You see?" she said. "Do you remember your wife's name? And the names of your children?"

"I wouldn't forget them," he said. "My wife's name was Mona." He stared at the wall for a moment, his face without expression. "I can still see the way she looked when I left to undergo treatment. Paul was—let's see, he must be about nine, maybe ten, by this time. And Wilma must be six or seven. I remember how scared she was that time she found a harmless little phytopod. She thought it was going to bite her."

"Phytopod?" said Carol. "We don't have them around here. What do they look like?"

"They're small and furry, and have two feet that look like roots. When they stand still you're likely to mistake them for plants."

"You do recall some things," said Carol.

"The little things that don't tell me where to look. I remember the time we went on a picnic—I don't recall how many moons there were in the sky—and the ground began to shake. It didn't do any damage, but Wilma was terrified. Paul took it in his stride, though."

"There aren't any earthquakes on Ganymede," said her father. "If your memory of that incident is correct, you're looking in the wrong place."

"I suppose so," he said. "But what's the right place?"

"Perhaps if you thought of a few more incidents, we might figure it out. It's the little things you don't forget that can be most helpful."

What nonsense, thought Carol, although she kept the thought to herself. The little things can be most harmful. They keep the pain, and the memory of pain, alive and vivid. She remembered little things about John all too well—the careless way he wore his clothes, and the way he combed his hair, the cigarettes he smoked, and the foods he liked to eat. And the stupid way she had let herself fall in love with him.

She hadn't even had the excuse of its happening suddenly, as it had happened now. She had begun to love John as she had come to know him, disregarding all the evidence of his selfishness, of his genuine inability to care for any one else than John Burr.

Unaware of what was going on in her mind, Callendar was saying, with somewhat more animation than he had previously shown, "I think you're right, Mr. Marsh. I've kept my troubles too much to myself. Maybe you can't actually do anything for me, but it wouldn't hurt me to talk. I should have done my talking long ago. When they found me."

"Where did they find you?" asked her father. "And what did you mean before, when you said you're not sure of anything?"

"They picked me up in a lifeboat, drifting some place between Mars and Jupiter. The motor was off, but the power pile was working, and the air-purifying equipment was on. I was apparently hibernating. I might have been that way for six months or a year."

"And you don't remember—" said Carol.

"There's plenty I don't remember, but as I've said, my memory isn't a complete blank. My wife and I and the kids had settled down in a new colony—exactly where it was is one of the things I forget. I believe now that it wasn't Ganymede. Maybe it was some other moon of Jupiter's.

"Anyway, I seem to recall having some trouble with my health, and being taken onto an inter-planetary hospital ship for treatment—L-treatment, they called it. That's where they put me to sleep. What happened after that, I can only guess. The ship must have been involved in some accident. I must have been transferred to the lifeboat."

"Alone?" asked Carol's father.

"No. There were two other patients with me. They were found dead. I was the only one left alive. The bodies of the crew members who transferred us weren't found at all. They might have gone back for more patients and then been unable to get away again."

"Who found your lifeboat?"

"The crew of a freighter, who spotted it drifting across a space lane. They took me on board and revived me. But they were in a hurry and didn't have much time to stay and investigate."

Mr. Marsh was thoughtful and silent.

Carol asked, "Weren't there any records in the lifeboat?"

"Nobody thought of that, at least not in the beginning. At first, when I regained consciousness, my mind was almost a complete blank. Then I began to remember things, but not enough. I couldn't recall where the colony had been, and after I had recovered enough to be able to get around, I began looking for my wife and children. I haven't come across a trace of them, although I've been on many worlds."

The food had long been ready and waiting. Until now, no one had thought of getting it. He stared as if through the wall and Carol, after she had set the dishes before him, had to remind him of their presence. When he did eat, it was automatically, without enjoyment.

Afterward, her father surprised Carol by saying, "Why not stay with us overnight, Mr. Callendar? We have an extra room, and tomorrow I may be able to give you a little helpful information."

The man's eyes came alive. "You're serious? You think that from what I told you, you'll be able to guess where I came from?"

"I used the word 'might.' Don't get your hopes up too much."

His face fell again. "Thanks for warning me," he said in a flat tone.

When, later on, he had gone to his room, Carol said, "Dad, do you really think you can help him?"

"That depends on your idea of help. Why are you so interested in him? Perhaps you're falling in love with him, Carol?"

"I think so."

"Under the circumstances, that's completely idiotic. Would there be any sense in asking why you fell in love with him?"

"Well, he looked so lost! I guess it's maternal—"

"As genuine a case of the grand passion as I've ever encountered," he said drily. "Almost as genuine as your previous experience."

Carol flushed. "He isn't like John."

"Fortunately, you are right. Burr was essentially a selfish baby. I can't imagine him spending his life looking for a wife and children he had lost. In future, Carol, if you must fall in love at all, do it suddenly. You choose much better that way."

"Yes, I know," she said. "Except for the fact that the wife and children may interfere. But don't worry, Dad. This time I'm not quitting my job and moving several million miles away to try to forget."

"There'll be no need for that." His face took on a troubled expression. "You'll have to face your problem right here."

"You haven't answered my question," said Carol. "Do you really think you can help him?"

"That isn't an easy one to answer. We'll have to prepare him for a shock, Carol. A first-class shock. That's why I wanted to be sure you were in love with him. It may make things easier for him to stand."

"What things?"

Her father hesitated. "Have you ever heard of this L-treatment he mentioned?"

She shook her head.

"I thought not. Carol," he said, and his voice was unexpectedly full of compassion, "you're going to have a very sick man on your hands. It won't be pleasant for either you or me, and it's going to be horrible for him. But it must be gone through. He must be told."

"For heaven's sake, what is it?"

"The L in L-treatment," he said slowly, "stands for longevity. That was what he was treated for. But you see now why it was found to be dangerous and discontinued. The reason you never heard of it is that it was developed and discarded two hundred years ago. Callendar wasn't adrift in space for a year or two, as he thinks. He was adrift for two centuries."

"No! Oh, no!"

"That's why the clothes in those pictures seemed odd. They've been in style and out again half a dozen times, with slight changes each time. That is why, furthermore, he can't find his wife and children on any of Jupiter's moons. The moons were first colonized ninety years ago."

"But he says—"

"He'll never see his wife and children again. They've lived their lives and died and been buried in the past. He should have died with them in his own time and not lived into ours."

"No," said Carol, "or I'd never have known him."

She was white and trembling, and her father pulled her to him and let her head rest on his shoulder.

Mr. Marsh said, "Perhaps you're right. I don't know. Anyway, he'll have to be told. And for your sake, I'd better do the telling."

Carol was silent, and they both thought of the sleeping man who didn't know that his old life had ended and that a new life was to begin so painfully in the morning.