He was watching the cobalt ball of the Meinz pendulum quiver on its thin quartz thread with the first fluttering release of Earth's gravity when the fear came.
Terror struck him suddenly, galvanically, blanking out all reason and all sensation. The control cubicle whirled giddily before his eyes, and the abysmal panic that gripped his mind was a monstrous thing boiling up out of unguessed subconscious depths. It froze him, breathing, like a man paralyzed under an overwhelming electric shock.
Then terror struck!
It was not fear of death. It was not even his own fear.
It was the blind panic of Something inside him whose existence he had never remotely suspected, Something that shrieked soundlessly in senseless maniac terror and fought to tear Itself free of him.
He was torn by the struggle for an interminable instant, and then it was over. He felt it writhe loose from the encumbrance of his mind, like a madman writhing out of a strait-jacket, and then It was falling back toward Earth, away from him. He could sense It plainly, once It was outside him—a malevolent, intangible Thing that fell back swiftly toward the emerald crescent of Earth.
He sat for a moment dazed while breath came back into his lungs and the steel-panelled cubicle grew steady again before his starting eyes. And, when It had gone in the distance and he could no longer feel the frenzy of Its terror, he felt the swift unbounded freedom that a spirited horse feels when it has, unexpectedly, lost its rider.