ed while on the train. The person who drugged him dropped
soluble salt paste on the rug of his room. Can we accept the fact that
the salt paste was used for EEG electrodes, and a recording made while
Marks was under the influence of the drug? We can't prove it, but what
other explanation can there be?"

Dr. Morrison shook his head. "Suppose we accept that theory. How does
that account for the other two? They were under guard, and there is no
evidence that they ever were drugged. If we accept your hypothesis, we
must also accept the theory that the other two men somehow were given
an EEG examination and their patterns recorded."

An idea was growing in Rick's mind. Suddenly he blurted, "That's where
the barber comes in!"

"The barber's machine was examined by Steve's men and found harmless,"
Hartson Brant pointed out.

Scotty spoke up quickly. "Yes, but when Duke looked at it this
morning, he found electrical connections! Why couldn't an EEG be taken
with such a gadget?"

Parnell Winston considered. "It could," he said finally. "I would
need to examine the machine, but in theory any gadget that fits over
the head could be adapted for proper placement of electrodes. The
recorder would be difficult to hide, however, unless it was in another
room."

Rick sank back and looked at Scotty. No wonder the barber had wanted
to give a treatment to Hartson Brant. The elevator operator's wink had
told him that the scientist had been on the fourth floor, where the
project team was located.

"Didn't you ever have your hair cut in the arcade shop, Dr. Morrison?"
Rick asked.

"No, Rick. I used a barber in a hotel nearby, one I've patronized for
years."

"But the other two did use the shop in the building," Scotty finished,
"and Dr. Marks had no need for a barber, so they had to get at him
some other way!"

"It seems reasonable," Hartson Brant admitted. "The pieces fall into
place nicely. But we must first accept Parnell's theory that some kind
of pattern can be transmitted that will interfere with normal brain
activity. If we believe it, we must also believe that the enemy is so
far ahead of us in brain physiology that we are hopelessly
outdistanced. I can't believe so much progress could have taken place
without some word of it leaking out."

Parnell Winston shrugged. "It seems incredible, Hartson. But we
haven't another theory, much less a better one."

"We had better make sure no one takes EEG's of the rest of us, in