"We might listen to the news," she suggested. "A premonition or two might be ruled out right away!"

Silently, he turned on the little radio. Automatically, he set it for the lowest volume they could hear distinctly.

The main item in the news was a baldly factual but toned-down report of the thing from the lake which had left the park and examined a small human town in detail and then had returned to the Park. There were reports of peculiar hoofprints found where the invaders had been. They were not the hoofprints of any earthly animal. There was an optimistic report from the scientists at work on the problem of the beam. Someone had come up with an idea and some calculations which seemed to promise that the beam would presently be duplicated. Once it was duplicated, of course a way to neutralize it could be found.

Lockley grunted. The broadcast was enthusiastic in its comments on the scientists. It talked gobbledegook which sounded as if it meant something but was actually nonsense. It barely touched on the fact that human beings were now ordered out of a much larger space than had been evacuated before. There was a statement from an important official that panic buying of food was both unnecessary and unwise. Lockley grunted again when the newscast ended.

"The idea that anything that can be duplicated can be canceled," he announced gloomily, "is unfortunately rot. We can duplicate sounds, but there's no way to make them cancel out! Not accurately!"

Jill had eaten a substantial part of the porcupine while the newscast was on. It was not a satisfying breakfast, but it cheered her immensely after two days of near-starvation.

"But," she observed, "maybe that won't apply to this business when you report what you know. It's not likely that anybody else has stood just outside a beam and made tests of what it's like and how it's aimed and so on."

They started off. For journeying in the Park, Lockley had the advantage that as part of the preparation for making a new map, he'd familiarized himself with all mapping done to date. He knew very nearly where he was. He knew within a close margin just where the terror beam stretched. He'd smashed his watch, which during sunshine substituted admirably for a compass, but he could maintain a reasonably straight line toward that part of the Park's border the terror beam would cross.

They moved doggedly over mountain-flanks and up valleys, and once they followed a winding hollow for a long way because it led toward their destination without demanding that they climb. It was in this area that, pushing through brushwood beside a running stream, they came abruptly upon a big brown bear. He was no more than a hundred feet away. He stared at them inquisitively, raising his nose to sniff for their scent.

Lockley bent and picked up a stone. He threw it. It clattered on rocks on the ground. The bear made a whuffing sound and moved aggrievedly away.