if he were listening to something very far away. A buzzer under his desk gave three short buzzes. He reached over and deflected the toggle on the intercom.

"Back already, Martha?" he said cheerily. "Any more left on your list for the Endore?"

Martha checked her list. There had been two left when she went to lunch. They had been checked off, too, while she was gone.

"That's all, Dr. Nale," she said.

"Good," came his voice through the intercom. "Think I'll go out and have something to eat myself."

The click of the intercom was followed at once by the opening of the inner office door. Martha's eyes watched Dr. Nale Hargrave as he walked through the office and out into the corridor.

Her eyes remained on the exit after he had gone, a faint frown creasing the smooth skin above her eyes. She had an IRRATIONAL impression that she had seen Dr. Bemis, the super, instead of Dr. Nale, and with his head bandaged clumsily.

She dismissed this with a pout and took a book out of a drawer to do her afternoon reading.

The buzzer on her desk buzzed a warning. She laid the book flat as the inner office door opened and Dr. Nale escorted Ren Gravenard out into the waiting room.

Martha glanced at her watch. It was ten after nine. Four minutes! She expected the nod from Dr. Nale. Her pencil wrote an O.K. after the dash she had drawn four minutes ago.

"Thank you doctor," Ren Gravenard was saying heartily. The two guards left by the side door back to quarantine.

Dr. Nale went over and bent close to Martha's ear.

"As your psychiatrist," he said pseudo-seriously, "I can advise you that unless you kiss me I am going to feel quite frustrated."

"Oh, that would never do!" Martha laughed, and kissed him.

She jerked back, startled. There was the sound of a shot from the inner office. The door was still open. Martha and Dr. Nale looked through the door, horrified.

Ren Gravenard was standing in the middle of the inner office dropping a flat automatic into his side pocket. There was an ugly wound on either side of his head from a bullet that had passed directly through his brain.

He smiled at them disarmingly, "It's quite all right. You see, it couldn't possibly do me any harm because I'm waiting for the elevator."

"Oh," they said, relieved. They bent and kissed each other again while Ren Gravenard went over to the mirror on the wall and dressed the wounds, wincing from the raw touch of the alcohol on wounded bone and flesh.

The outer door opened and two men came in with a wicker basket.

Dr. Nale pointed over in the corner where one of the guards lay dead.

"What happened to him, Doc?" one of the men asked.

"He got shot through the head," Dr. Hargrave explained. "One of the men off the Endore did it. They're all being taken over to observation. I think I'll have to go over with them. I'm beginning to get an inkling of what's going on, and I'm very much afraid of what I think it is."

The two men set the basket down and lifted the wicker lid. Dr. Bemis came out of the inner office and laid down in the corner. The two men waited until he had settled himself, then lifted him into the basket.

Dr. Hargrave held open the outer door for them. He returned to the desk beside Martha and took a gun out of his coat pocket. He pointed it at her, frowned in indecision, then slowly, with perspiration standing out on his forehead, pulled out the clip and emptied the barrel of the gun.

"Good for you," Martha said. She picked up her book and started reading. Dr. Hargrave put the gun back in his pocket and went to the door.

"Take a few days off starting tomorrow," he said before going out. "I'm going to be slowly going crazy trying to figure this mess out. That's why I insisted to Dr. Bemis that I be confined with the crew of the Endore—just in case."

His heels made loud noises on the marble floor of the corridor. He pushed through the revolving doors to the sidewalk.

There was an argument going on between a small newsboy and an elderly gentlemen type of man.

"I tell you there's only two pennies," the boy insisted.

"There's four," the man insisted just as strongly. "See?"

He pried open the boy's fingers and looked.

"Sorry," he said. "You're right." His hand went into his pocket to make up the deficit.

"Hey! Wait a minute," the boy said. "I was wrong. You gave me two pennies too much."

A small pudgy finger took two of the pennies. The boy glanced at the others to make sure the right number were left.

Nale was close enough to see what happened. He saw the pennies taken from what seemed to be seven or eight in the boy's palm. When the two were taken away there seemed to be a slight blur—and there was only a solitary penny left.

He didn't wait. The paper boy and the customer were still patiently arguing as he climbed into his car and drove away. He drove slowly with his foot close to the brakes.

Although his eyes were warily watching each car on the street, his mind was busy. He was trying to figure out who had been shot.

"It might even have been me!" he thought. And there was no way of knowing.

He drove the car another block. There was doubt growing in his mind. On a sudden impulse he pulled the car over to the curb and stopped the motor. Getting out, he started walking rapidly. There would be three miles of walking before he reached observation, but it would be safer to walk.

A block further he stopped abruptly in surprise. The spaceport observation hospital was just in front of him.

"I should have guessed," he muttered as he pushed through the heavy doors. "The speedometer, of course. Naturally it would go first."

Martha Ryan saw the door close on Dr. Hargrave, then started reading again. She finished the page and turned it over. The first few words of the opposite side of the sheet showed the continuity to be difficult.

Thinking she might have turned two sheets by mistake, she turned back one. It was still wrong. She sighed exasperatedly. She distinctly remembered that she had been on page twenty-five, so the next page should be twenty-six. Since it hadn't been, she would have to look for twenty-six.

She looked through the book, page by page, and it wasn't there. Getting over her exasperation she made a game of it. Finally she developed to the stage where she would open the book at random, note the number of the page, close the book, and then try to find that page she had just seen.

It was a very peculiar book. She found that, (a) she could find any page number she wasn't looking for, and (b) any page number she looked for was not in the book, even though it had been a moment before.

Resting thoughtfully for several minutes on this achievement of deduction she decided to try another experiment. She counted the number of sheets of paper in the book and wrote the number down. It was one hundred twenty-four.

Then she counted them again. There were one hundred eighty-six. She counted them five more times, making seven times she had counted them. She got nine different numbers of sheets in the book. She decided she couldn't get nine different numbers after counting only seven times, and counted the numbers. There were five. She closed her eyes and counted to ten rapidly, then counted them again. There were fourteen.

She held out her hands. She had seven fingers on her right hand and three on her left. She chuckled dryly and thought, "Well, anyway there are ten altogether." She counted them to be sure, and there were thirteen.

Pursing her lips stubbornly she held up two fingers and counted them. There were two. She held them rigid and closed her eyes, counting rapidly to ten. Opening her eyes she looked cautiously at the upraised fingers. There were two.

She raised a third finger to join the other two, and there were five upraised fingers. Not only that, there were seven of them