It turned out to be a single, rather small white building with a fence around it. The fence bothered Malone a little, but there was no need to worry; this time he was introduced at once into Dr. O’Connor’s office. It was panelled in wallpaper manufactured to look like pine. and the telepathy expert sat behind a large black desk bigger than any Malone had ever seen in the FBI offices. There wasn’t a scrap of paper on the desk; its surface was smooth and shiny, and behind it the nearly transparent Dr. Thomas O’Connor was close to invisible.

He looked, in person, just about the same as he’d looked on the FBI tapes. Malone closed the door of the office behind him, looked for a chair and didn’t find one. In Dr. O’Connor’s office, it was perfectly obvious, Dr. O’Connor sat down. You stood, and were uncomfortable.

Malone took off his hat. He reached across the desk to shake hands with the telepathy expert, and Dr. O’Connor gave him a limp fragile paw. “Thanks for giving me a little time,” Malone said. “I really appreciate it.” He smiled across the desk. His feet were already beginning to hurt.

“Not at all,” Dr. O’Connor said, returning the smile with one of his own special quick-frozen brand. “I realize how important FBI work is to all of us, Mr. Malone. What can I do to help you?”

Malone shifted his feet. “I’m afraid I wasn’t very specific on the phone last night,” he said. “It wasn’t anything I wanted to discuss over a line that might have been tapped. You see, I’m on the telepathy case.”

Dr. O’Connor’s eyes widened the merest trifle. “I see,” he said. “Well, I’ll certainly do everything I can to help you.”

“Fine,” Malone said. “Let’s get right down to business, then. The first thing I want to ask you about is this detector of yours. I understand it’s too big to carry around — but how about making a smaller model?”

“Smaller?” Dr. O’Connor permitted himself a ghostly chuckle. “I’m afraid that isn’t possible, Mr. Malone. I would be happy to let you have a small model of the machine if we had one available — more than happy. I would like to see such a machine myself, as a matter of fact. Unfortunately, Mr. Malone—”

“There just isn’t one, right?” Malone said.

“Correct,” Dr. O’Connor said. “And there are a few other factors. In the first place, the person being analyzed has to be in a specially shielded room, such as is used in encephalographic analysis. Otherwise, the mental activity of the other persons around him would interfere with the analysis.” He frowned a little. “I could wish that we knew a bit more about psionic machines. The trouble with the present device, frankly, is that it is partly psionic and partly electronic, and we can’t be entirely sure where one part leaves off and the other begins. Very trying. Very trying indeed.”

“I’ll bet it is,” Malone said sympathetically, wishing he understood what Dr. O’Connor was talking about.

The telepathy expert sighed. “However,” he said, “we keep working at it.” Then he looked at Malone expectantly.

Malone shrugged. “Well, if I can’t carry the thing around, I guess that’s that,” he said. “But here’s the next question: do you happen to know the maximum range of a telepath? I mean: how far away can he get from another person and still read his mind?”

Dr. O’Connor frowned again. “We don’t have definite information on that, I’m afraid,” he said. “Poor little Charlie was rather difficult to work with. He was mentally incapable of co-operating in any way, you see.”

“Little Charlie?”

“Charles O’Neill was the name of the telepath we worked with,” Dr. O’Connor explained.

“I remember,” Malone said. The name had been on one of the tapes, but he just hadn’t associated “Charles O’Neill” with “Little Charlie.” He felt as if he’d been caught with his homework undone. “How did you manage to find him, anyway?” he said. Maybe, if he knew how Westinghouse had found their imbecile-telepath, he’d have some kind of clue that would enable him to find one, too. Anyhow, it was worth a try.

“It wasn’t difficult in Charlie’s case,” Dr. O’Connor said. He smiled. “The child babbled all the time, you see.”

“You mean he talked about being a telepath?”

Dr. O’Connor shook his head impatiently. “No,” he said. “Not at all. I mean that he babbled. Literally. Here: I’ve got a sample recording in my files.” He got up from his chair and went to the tall gray filing cabinet that hid in a far corner of the pine-panelled room. From a drawer he extracted a spool of common audio tape, and returned to his desk.

“I’m sorry we didn’t get full video on this,” he said, “but we didn’t feel it was necessary.” He opened a panel in the upper surface of the desk, and slipped the spool in. “If you like, there are other tapes—”

“Maybe later,” Malone said.

Dr. O’Connor nodded and pressed the playback switch at the side of the great desk. For a second the room was silent.

Then there was the hiss of empty tape, and a brisk masculine voice that overrode it:

“Westinghouse Laboratories,” it said, “sixteen April nineteen-seventy. Dr. Walker speaking. The voice you are about to hear belongs to Charles O’Neill: chronological age fourteen years, three months; mental age, approximately five years. Further data on this case will be found in the file O’Neill.”

There was a slight pause, filled with more tape hiss.

Then the voice began.

“…push the switch for record… in the park last Wednesday… and perhaps a different set of… poor kid never makes any sense in… trees and leaves all sunny with the… electronic components of the reducing stage might be… not as predictable when others are around but… to go with Sally some night in the…”

It was a childish, alto voice, gabbling in a monotone. A phrase would be spoken, the voice would hesitate for just an instant, and then another, totally disconnented phrase would come. The enunciation and pronunciation would vary from phrase to phrase, but the tone remained essentially the same, drained of all emotional content.

“…in receiving psychocerebral impulses there isn’t any… nonsense and nothing but nonsense all the… tomorrow or maybe Saturday with the girl… tube might be replaceable only if… something ought to be done for the… Saturday would be a good time for… work on the schematics tonight if…”

There was a click as the tape was turned off, and Dr. O’Connor looked up.

“It doesn’t make much sense,” Malone said. “But the kid sure has a hell of a vocabulary for an imbecile.”

“Vocabulary?” Dr. O’Connor said softly.

“That’s right,” Malone said. “Where’d an imbecile get words like ‘psychocerebral?’ I don’t think I know what that means, myself.”

“Ah,” Dr. O’Connor said. “But that’s not his vocabulary, you see. What Charlie is doing is simply repeating the thoughts of those around him. He jumps from mind to mind, simply repeating whatever he receives.” His face assumed the expression of a man remembering a bad taste in his mouth. “That’s how we found him out, Mr. Malone,” he said. “It’s rather startling to look at a blithering idiot and have him suddenly repeat the very thought that’s in your mind.”

Malone nodded unhappily. It didn’t seem as if O’Connor’s information was going to be a lot of help as far as catching a telepath was concerned. An imbecile, apparently, would give himself away if he were a telepath. But nobody else seemed to be likely to do that. And imbediles didn’t look like very good material for catching spies with.

Then he brightened. “Doctor, is it possible that the spy we’re looking for really isn’t a spy?”

“Eh?”

“I mean, suppose he’s an imbecile, too? I doubt whether an imbecile would really be a spy, if you see what I mean.”

Dr. O’Connor appeared to consider the notion. After a little while he said: “It is, I suppose, possible. But the readings on the machine don’t give us the same timing as they did in Charlie’s case — or even the same sort of timing.”