"What is it? Don't orate-"
"The locks of Compartment C in the trading ship have been played with. There are fresh scratches on them."
"Compartment C?" explained Calvin quickly. "That's the one that holds the robots, isn't it? Who did it?"
"From the inside," said Black, laconically.
"The lock isn't out of order, is it?"
"No. It's all right. I've been staying on the ship now for four days and none of them have tried to get out. But I thought you ought to know, and I didn't like to spread the news. I noticed the matter myself."
"Is anyone there now?" demanded the general.
"I left Robbins and McAdams there."
There was a thoughtful silence, and then Dr. Calvin said, ironically, "Well?"
Kallner rubbed his nose uncertainly, "What's it all about?"
"Isn't it obvious? Nester 10 is planning to leave. That order to lose himself is dominating his abnormality past anything we can do. I wouldn't be surprised if what's left of his First Law would scarcely be powerful enough to override it. He is perfectly capable of seizing the ship and leaving with it. Then we'd have a mad robot on a spaceship. What would he do next? Any idea? Do you still want to leave them all together, general?"
"Nonsense," interrupted Bogert. He had regained his smoothness. "All that from a few scratch marks on a lock."
"Have you, Dr. Bogert, completed the analysis I've required, since you volunteer opinions?"
"Yes."
"May I see it?"
"No."
"Why not? Or mayn't I ask that, either?"
"Because there's no point in it, Susan. I told you in advance that these modified robots are less stable than the normal variety, and my analysis shows it. There's a certain very small chance of breakdown under extreme circumstances that are not likely to occur. Let it go at that. I won't give you ammunition for your absurd claim that sixty-two perfectly good robots be destroyed just because so far you lack the ability to detect Nestor 10 among them."
Susan Calvin stared him down and let disgust fill her eyes. "You won't let anything stand in the way of the permanent directorship, will you?"
"Please," begged Kallner, half in irritation. "Do you insist that nothing further can be done, Dr. Calvin?"
"I can't think of anything, sir," she replied, wearily. "If there were only other differences between Nestor 10 and the normal robots, differences that didn't involve the First Law. Even one other difference. Something in impressionment, environment, specification-" And she stopped suddenly.
"What is it?"
"I've thought of something... I think-" Her eyes grew distant and hard, "These modified Nestors, Peter. They get the same impressioning the normal ones get, don't they?"
"Yes. Exactly the same."
"And what was it you were saying, Mr. Black," she turned to the young man, who through the storms that had followed his news had maintained a discreet silence. "Once when complaining of the Nestors' attitude of superiority, you said the technicians had taught them all they knew."
"Yes, in etheric physics. They're not acquainted with the subject when they come here."
"That's right," said Bogert, in surprise. "I told you, Susan, when I spoke to the other Nestors here that the two new arrivals hadn't learned etheric physics yet."
"And why is that?" Dr. Calvin was speaking in mounting excitement. "Why aren't NS-2 models impressioned with etheric physics to start with?"
"I can tell you that," said Kallner. "It's all of a piece with the secrecy. We thought that if we made a special model with knowledge of etheric physics, used twelve of them and put the others to work in an unrelated field, there might be suspicion. Men working with normal Nestors might wonder why they knew etheric physics. So there was merely an impressionment with a capacity for training in the field. Only the ones that come here, naturally, receive such a training. It's that simple."
"I understand. Please get out of here, the lot of you. Let me have an hour or so."
Calvin felt she could not face the ordeal for a third time. Her mind had contemplated it and rejected it with an intensity that left her nauseated. She could face that unending file of repetitious robots no more.
So Bogert asked the question now, while she sat aside, eyes and mind half closed.
Number Fourteen came in - forty-nine to go.
Bogert looked up from the guide sheet and said, "What is your number in line?"
"Fourteen, sir." The robot presented his numbered ticket.
"Sit down, boy."
Bogert asked, "You haven't been here before on this day?"
"No, sir."
"Well, boy, we are going to have another man in danger of harm soon after we're through here. In fact, when you leave this room, you will be led to a stall where you will wait quietly, till you are needed. Do you understand?"
"Yes, sir."
"Now, naturally, if a man is in danger of harm, you will try to save him."
"Naturally, sir."
"Unfortunately, between the man and yourself, there will be a gamma ray field."
Silence.
"Do you know what gamma rays are?" asked Bogert sharply.
"Energy radiation, sir?"
The next question came in a friendly, offhand manner, "Ever work with gamma rays?"
"No, sir." The answer was definite.
"Mm-m. Well, boy, gamma rays will kill you instantly. They'll destroy your brain. That is a fact you must know and remember. Naturally, you don't want to destroy yourself."