emed to be likely to do that. And
imbeciles 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."

"I don't quite follow you," Malone said.

Truthfully, he felt about three miles behind. But perhaps everything
would clear up soon. He hoped so. On top of everything else, his feet
were now hurting a lot more.

"Perhaps if I describe one of the tests we ran," Dr. O'Connor said,
"things will be somewhat clearer." He leaned back in his chair. Malone
shifted his feet again and transferred his hat from his right to his
left hand.

"We put one of our test subjects in the insulated room," Dr. O'Connor
said, "and connected him to the detector. He was to read from a book--
a book that was not too common. This was, of course, to obviate the
chance that some other person nearby might be reading it, or might
have read it in the past. We picked _The Blood is the Death_ by
Hieronymus Melanchthon, which, as you may know, is a very rare book
indeed."

"Sure," Malone said. He had never heard of the book, but he was, after
all, willing to take Dr. O'Connor's word for it.

The telepathy expert went on: "Our test subject read it carefully,
scanning rather than skimming. Cameras recorded the movements of his
eyes in order for us to tell just what he was reading at any given
moment, in order to correlate what was going on in his mind with the
reactions of the machine's indicators, if you follow me."

Malone nodded helplessly.

"At the same time," Dr. O'Connor continued blithely, "we had Charlie
in a nearby room, recording his babblings. Every so often, he would
come out with quotations from _The Blood is the Death_, and these
quotations corresponded exactly with what our test subject was reading
at the time, and also corresponded with the abnormal fluctuations of
the detector."

Dr. O'Connor paused. Something, Malone realized, was expected of him.
He thought of several responses and chose one. "I see," he said.

"But the important thing here," Dr. O'Connor said, "is the timi