"Just a moment, doctor," Burris said. He was eying the machine with a combination of suspicion and awe. "A while back you mentioned something about "outside influences." Just what, specifically, does that mean?"

With some regret, Dr. O"Connor dropped the lead. "Telepathy," he said.

"By outside influences, I meant influences on the mind, such as telepathy or mind reading of some nature."

"I see," Burris said. "You can detect a telepath with this machine."

"I"m afraid--"

"Well, some kind of a mind reader anyhow," Burris said. "We won"t quarrel about terms."

"Certainly not," Dr. O"Connor said. The smile he turned on Burris was as cold and empty as the inside of Orbital Station One. "What I meant was ... if you will permit me to continue ... that we cannot detect any sort of telepath or mind reader with this device. To be frank, I very much wish that we could; it would make everything a great deal simpler.

However, the laws of psionics don"t seem to operate that way."

"Well, then," Burris said, "what does the thing do?" His face wore a mask of confusion. Momentarily, Malone felt sorry for his chief. He could remember how he"d felt, himself, when that law professor had come up with a particularly baffling question in cla.s.s.

"This machine," Dr. O"Connor said with authority, "detects the slight variations in mental activity that occur when a person"s mind is _being_ read."

"You mean, if my mind were being read right now--"

"Not right now," Dr. O"Connor said. "You see, the bulk of this machine is in Nevada; the structure is both too heavy and too delicate for transport. And there are other qualifications--"

"I meant theoretically," Burris said.

"Theoretically," Dr. O"Connor began, and smiled again, "if your mind were being read, this machine would detect it, supposing that the machine were in operating condition and all of the other qualifications had been met. You see, Mr. Burris, no matter how poor a telepath a man may be, he has some slight ability--even if only very slight--to detect the fact that his mind is being read."

"You mean, if somebody were reading my mind, I"d know it?" Burris said.

His face showed, Malone realized, that he plainly disbelieved this statement.

"You would know it," Dr. O"Connor said, "but you would never know you knew it. To elucidate: in a normal person--like you, for instance, or even like myself--the state of having one"s mind read merely results in a vague, almost subconscious feeling of irritation, something that could easily be attributed to minor worries, or fluctuations in one"s hormonal balance. The hormonal balance, Mr. Burris, is--"

"Thank you," Burris said with a trace of irritation. "I know what hormones are."

"Ah. Good," Dr. O"Connor said equably. "In any case, to continue: this machine interprets those specific feelings as indications that the mind is being ... ah ... "eavesdropped" upon."

You could almost see the quotation marks around what Dr. O"Connor considered slang dropping into place, Malone thought.

"I see," Burris said with a disappointed air. "But what do you mean, it won"t detect a telepath? Have you ever actually worked with a telepath?"

"Certainly we have," Dr. O"Connor said. "If we hadn"t, how would we be able to tell that the machine was, in fact, indicating the presence of telepathy? The theoretical state of the art is not, at present, sufficiently developed to enable us to--"

"I see," Burris said hurriedly. "Only wait a minute."

"Yes?"

"You mean you"ve actually got a real mind reader? You"ve found one? One that works?"

Dr. O"Connor shook his head sadly. "I"m afraid I should have said, Mr.

Burris, that we did once have one," he admitted. "He was, unfortunately, an imbecile, with a mental age between five and six, as nearly as we were able to judge."

"An imbecile?" Burris said. "But how were you able to--"

"He could repeat a person"s thoughts word for word," Dr. O"Connor said.

"Of course, he was utterly incapable of understanding the meaning behind them. That didn"t matter; he simply repeated whatever you were thinking. Rather disconcerting."

"I"m sure," Burris said. "But he was really an imbecile? There wasn"t any chance of--"

"Of curing him?" Dr. O"Connor said. "None, I"m afraid. We did at one time feel that there had been a mental breakdown early in the boy"s life, and, indeed, it"s perfectly possible that he was normal for the first year or so. The records we did manage to get on that period, however, were very much confused, and there was never any way of telling anything at all, for certain. It"s easy to see what caused the confusion, of course: telepathy in an imbecile is rather an oddity--and any normal adult would probably be rather hesitant about admitting that he was capable of it. That"s why we have not found another subject; we must merely sit back and wait for lightning to strike."

Burris sighed. "I see your problem," he said. "But what happened to this imbecile boy of yours?"

"Very sad," Dr. O"Connor said. "Six months ago, at the age of fifteen, the boy simply died. He simply--gave up, and died."

"Gave up?"

"That was as good an explanation as our medical department was able to provide, Mr. Burris. There was some malfunction, but--we like to say that he simply gave up. Living became too difficult for him."

"All right," Burris said after a pause. "This telepath of yours is dead, and there aren"t any more where he came from. Or if there are, you don"t know how to look for them. All right. But to get back to this machine of yours: it couldn"t detect the boy"s ability?"

Dr. O"Connor shook his head. "No, I"m afraid not. We"ve worked hard on that problem at Westinghouse, Mr. Burris, but we haven"t yet been able to find a method of actually detecting telepaths."

"But you can detect--"

"That"s right," Dr. O"Connor said. "We can detect the fact that a man"s mind is being read." He stopped, and his face became suddenly morose.

When he spoke again, he sounded guilty, as if he were making an admission that pained him. "Of course, Mr. Burris, there"s nothing we can _do_ about a man"s mind being read. Nothing whatever." He essayed a grin that didn"t look very healthy. "But at least," he said, "you know you"re being spied on."

Burris grimaced. There was a little silence while Dr. O"Connor stroked the metal box meditatively, as if it were the head of his beloved.

At last, Burris said: "Dr. O"Connor, how sure can you be of all this?"

The look he received made all the previous conversation seem as warm and friendly as a Christmas party by comparison. It was a look that froze the air of the room into a solid chunk, Malone thought, a chunk you could have chipped pieces from, for souvenirs, later, when Dr. O"Connor had gone and you could get into the room without any danger of being quick-frozen by the man"s unfriendly eye.

"Mr. Burris," Dr. O"Connor said in a voice that matched the temperature of his gaze, "please. Remember our slogan."

Malone sighed. He fished in his pocket for a pack of cigarettes, found one, and extracted a single cigarette. He stuck it in his mouth and started fishing in various pockets for his lighter.

He sighed again. He preferred cigars, a habit he"d acquired from the days when he"d filched them from his father"s cigar case, but his mental picture of the fearless and alert young FBI agent didn"t include a cigar. Somehow, remembering his father as neither fearless nor, exactly, alert--anyway, not the way the movies and the TV screens liked to picture the words--he had the impression that cigars looked out of place on FBI agents.

And it was, in any case, a small sacrifice to make. He found his lighter and shielded it from the brisk wind. He looked out over water at the Jefferson Memorial, and was surprised that he"d managed to walk as far as he had. Then he stopped thinking about walking, and took a puff of his cigarette, and forced himself to think about the job in hand.

Naturally, the Westinghouse gadget had been declared Ultra Top Secret as soon as it had been worked out. Virtually everything was, these days.

And the whole group involved in the machine and its workings had been transferred without delay to the United States Laboratories out in Yucca Flats, Nevada.

Out there in the desert, there just wasn"t much to do, Malone supposed, except to play with the machine. And, of course, look at the scenery.

But when you"ve seen one desert, Malone thought confusedly, you"ve seen them all.