Then the unseen object did something. The terror beam that flicked back and forth doubled in intensity. The soldiers just reentering Maplewood smelled foulness and saw bright lights. Bellowings deafened them. They fell with every muscle rigid in spasm. Beyond them other men were paralyzed. For five minutes the invaders' mobile weapon paralyzed all living things for a distance of fifteen miles. Then for thirty seconds it paralyzed living things for a distance of thirty miles. For a bare instant it convulsed men and animals for a greater distance yet. And all these victims of the terror beam knew, thereafter, an invincible horror of the beam.
The thing from the Park which nobody had seen went back into the Park. And then men were permitted to return to exactly the same places they'd been allowed to occupy before the thing began its excursion.
It seemed that nothing was changed, but everything was changed. If there were mobile carriers of the invasion weapon, then victory could not be had by a single atom bomb fired into Boulder Lake. There might be a dozen separate mobile terror beam generators scattered through the Park. Any atomic attack would need to be multiplied in its violence to be certain of results. Instead of one bomb there might be a need for fifty. They would have to destroy the Park utterly, even its mountains. And the fallout from so many atom bombs simply could not be risked. The invaders were effectively invulnerable.
While this undesirable situation was being demonstrated, Jill slept heavily between two roots of a very large tree, and Lockley dozed against a nearby tree trunk. He believed that he guarded Jill most vigilantly.
He awoke at dawn with the din of bird song in his ears. Jill opened her eyes at almost the same instant. She smiled at him and tried to get up. She was stiff and sore from the hardness of the ground on which she'd slept. But it was a new day, and there was breakfast. It was porcupine cooked the night before.
"Somehow," said Jill as she nibbled at a bone, "somehow I feel more cheerful than I did."
"That's a mistake," Lockley told her. "Start out with a few premonitions and the day improves as they turn out wrong. But if you start out hoping, the day ends miserably with most of your hopes denied."
"You've got premonitions?" she asked.
"Definitely," he said.
It was true. As yet he knew nothing of last night's temporary occupation of a human town, but he believed he knew how the terror beam worked even if he couldn't figure out a way to generate it. He could imagine no defense against it. But if Jill had awakened feeling cheerful, there was no reason to depress her. She'd have reason enough to be dejected later, beginning with proof of Vale's death and going on from there.