"Sound, Johnny, sound. Or rather, vibration. It's something we're just beginning to learn about. We know a few things; we know you can boil water with sound if the frequency is high enough. And you can drill metal with it—and it does things to the human body.
"There are frequencies of sound which can act directly on human nerves, directly on the human brain. It means that if we know the right frequency, we'll be able to produce any state we want in a man, any emotion. Fear, anguish, anything.
"When the steering rockets were cut in, the Ship began to vibrate. It generated frequencies so high that ordinary human senses couldn't detect them. And when your nerves were exposed to those vibrations, it produced fear. Pure and absolute fear. Motor control went, rational processes went, all the nervous functions of the body went out of control. Your body became a giant tuning fork, and the frequency to which it vibrated was fear.
"I can't remember—"
"Sanity went, too, Johnny," said the man softly. "You could not stand that fear and remain sane, so something cut off. That was what happened to Mitch."
"How did I get back?"
"We don't know. The films show your face suddenly going blank. Then you flew. That's all. We hoped you could tell us."
"No. No—I don't remember—"
"There was something in you so strong it overrode everything else, even the fear. We'd like to know what it is. We'll find out, Johnny, and it will mean a lot to the human race when we do."
This is my day.