A telepathic species was on the march. What was Earth going to do about it? A lot of speculation necessarily clothed the bare bones of Jones' information. Evidently the species could take over a mind with ease. With Everset, it seemed that they had insinuated their thoughts into his, delicately altering his previous convictions. They had possessed him with remarkable ease. How about Jones? Why hadn't they taken him? Was distance a factor? Or hadn't they been prepared for the suddenness of his departure? One thing was certain. Everything Everset knew, the enemy knew. That meant they knew where Earth was, and how defenseless the planet was to their form of attack. It could be expected that they were on their way. Something was needed to nullify their tremendous advantage. But what sort of something? What armor is there against thought? How do you dodge a wavelength? Pouch-eyed scientists gravely consulted their periodic tables. And how do you know when a man has been possessed? Although the enemy was clumsy with Everset, would they continue to be clumsy? Wouldn't they learn? Psychologists tore their hair and bewailed the absence of an absolute scale for humanity. Of course, something had to be done at once. The answer, from a technological planet, was a technological one. Build a space fleet and equip it with some sort of a detection-fire network. This was done in record time. The Attison Detector was developed, a cross between radar and the electroencephalograph. Any alteration from the typical human brain wave pattern of the occupants of a Detector-equipped ship would boost the indicator around the dial. Even a bad dream or a case of indigestion would jar it. It seemed probable that any attempt to take over a human mind would disturb something. There had to be a point of interaction, somewhere. That was what the Attison Detector was supposed to detect. Maybe it would. The spaceships, three men to a ship, dotted space between Earth and Mars, forming a gigantic sphere with Earth in the center. Tens of thousands of men crouched behind gunfire panels, watching the dials on the Attison Detector. The unmoving dials. * * * * * "Do you think I could fire a couple of bursts?" Edwardson asked, his fingers on the gunfire button. "Just to limber the guns?" "Those guns don't need limbering," Cassel said, stroking his beard. "Besides, you'd throw the whole fleet into a panic." "Cassel," Morse said, very quietly. "Get your hand off your beard." "Why should I?" Cassel asked. "Because," Morse answered, almost in a whisper, "I am about to ram it right down your fat throat." Cassel grinned and tightened his fists. "Pleasure," he said. "I'm tired of looking at that scar of yours." He stood up. "Cut it," Edwardson said wearily. "Watch the birdie." "No reason to, really," Morse said, leaning back. "There's an alarm bell attached." But he looked at the dial.