reading.

But Mark wasn't actually interested in his answer. He ran outside. "Arkem!" he called. "Arkem!"

There was nothing he could interpret as an answer. After a moment or two he came into the ship again, his face betraying his disappointment. "I guess he doesn't hear me. He's too far away."

Sam nodded. He had put the translation down and was staring straight ahead of him, as if looking through the ship's side.

"Is anything the matter, Pop?"

"What? Oh, no, nothing's the matter. I was just thinking about what I read here."

"They had an accident, didn't they? How did it happen?"

"It happened because their ship wasn't as good as ours. Julian Hagstrom, the man who was killed, was buried here by his brother. Raoul put this record in the stone to mark his grave. I think he also engraved something on the stone itself. But that's been worn away."

"It must have been a long time ago. Maybe years."

"Yes, it was years ago. After he buried Julian, Raoul tried to make repairs, and headed in a direction where he hoped he'd find a civilized planet. He never made it."

"How can you know that? He wrote the paper before he started out."

"If he had made it, we'd have heard of him. We'd certainly have heard of him." Sam's face was bleak. "And Rhoda—your mother—would still be alive."

Mark looked puzzled, and stared at the translation once more. "It says here he tried to re-reverse the aging process. What does that mean? And what's immortality, Pop?"

"Something he and his brother were looking for. Something to keep people from ever dying. They had a ship full of dogs and other animals. All died in their experiments—all but Arkem. They had high hopes of Arkem. He lived through a number of different treatments and became quite a pet of Julian's. Then came the crash. Their method wasn't proof against accidental death, and at any rate they hadn't applied it yet to themselves.

"After Raoul buried his brother, the dog was miserable, and howled so much that Raoul decided to leave him behind. He was helped to reach this decision by the fact that the ship had lost much of its air in the accident, and he knew that the air-purifying mechanism wasn't working too well. He figured he'd have a better chance of surviving if he stayed in the ship alone. But it didn't do him any good. He was lost in space, or we'd certainly have heard of him."

From outside there came the sound of a low growl. "It's Arkem!" cried Mark. "Now you'll see. Wait till he hears me call his name."

He ran out, and Sam followed slowly. "Don't expect too much, Mark," he said, almost with pity.

Mark didn't hear him. "Arkem!" he called. "Arkem! Arkem!"

The dog was watchful, keeping his distance and giving no sign of recognition. Sam put his arm around his son's shoulder.

"Arkem, Arkem! Here, Arkem!"

The dog snarled.

There were tears in the boy's eyes. "He doesn't know his own name! He doesn't even know his own name! Arkem!"

"It's no use, Mark, he's forgotten he ever had a name. I'm afraid you'd better give up the idea of having him as a pet."

"But you can't forget your own name!"

"You can in eight hundred years. Yes, Mark, that's when all this happened, eight hundred years ago. That's why the language had to be translated. Arkem is immortal. And during his long life he's forgotten not only his name, but the master for whose sake he was marooned here. If Julian Hagstrom were, by some miracle, to come back to life, I'm sure the dog wouldn't remember him. All he has is a vague but strong tie to that heap of stones. He no longer knows why he's protecting it. He's been away from live human beings so long that his brain is little more than a bundle of reflexes and instincts."

"I'll train him," said Mark. "Sometimes you forget a thing at first, but it comes back to you later. He'll remember his name—here, Arkem!"