CLOSE TO CRITICAL

couldn't fly because it was broken, and there had been no mention of a hill—at least, not of anything unusual in that respect—in the description of the machine's environment. As a matter of fact, they recalled, it had been stated to lie at the foot of a hill.

Then John remembered Nick's tale of a remarkably high hill in the region, and the two got out their maps once more. It seemed possible though far from certain, after careful checking, that the light was on the hill; but if that were the case it seemed to dispose of any remaining chance that they had found the bathyscaphe. Since the only other possibility they could envision was that Swift's people were there with a fire, a slight problem developed.

It would be raining before long, and travel without torches would be impossible. If the area ahead were actually a camp of Swift's cave dwellers, approaching it with torches would simply be asking for capture. Of course, the chief might have accepted Fagin's offer, so that they would technically be allies; but from what John and Nancy knew of Swift they didn't want to take the chance. From one point of view, there was no reason to approach at all, since they were searching for the bathyscaphe rather than scouting the cave men; but this phase of the matter didn't occur to either of them. If it had, they would probably have insisted that they weren't sure the light wasn't from the crippled machine. Anyway, they kept trying to plan a method of approach to the light.

It was Nancy who finally worked it out. John didn't like the plan and didn't trust it. Nancy pointed out truthfully that she knew more physics than he did, and even if he didn't know what she was talking about he ought to take her word for it. He replied, equally truthfully, that he might be a mathematician rather than a chemist but even he knew enough about rain not to accept ideas like hers uncritically. Nancy finally won her point by the simple process of starting toward the light alone, giving John the choice of coming or staying behind. He came.

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Raeker would have liked to hear that argument. He had named the little creatures who had emerged from the stolen eggs quite arbitrarily, and still had no idea of the actual gender of any of them. Nancy's display of a human-feminine characteristic would have been fascinating if not very conclusive.

John watched the sky uneasily as they strode onward. Inwardly he knew perfectly well that the rain was not due for a while yet; but the mere fact of Nancy's defiance of the phenomenon made him abnormally conscious of it. By the time the first drops actually appeared far above, they were close enough to the light to see that something lay between them and the actual source—it was shining from behind a barrier of some sort, presumably a hill.

"Should we go over, or around?" John asked, when this fact became evident. "If we go up, we'll run into the rain sooner."

"That's a good reason for doing it," retorted Nancy. "If it is the cave people they won't be expecting us from that direction, and you'll see all the sooner that I'm right. Besides, I've never been up a really high hill, and Nick said this one was two or three hundred feet tall—remember?"

"I remember, but I'm not as sure as you seem to be that this is the hill he was talking about."

"Look at your map!"

"All right, I know we're close to it, but his notes were pretty rough; you know that as well as I do. There never was time to make a decent map of the country he covered, after he got back. We've been fighting or moving practically ever since."

"All right, you needn't make a thesis out of it. Come on." She led the way without waiting for an answer.

For some time there was no appreciable rise in the general ground level, though the number of ordinary hillocks remained about as usual. The first implication that Nancy might be right about the nature of the hill

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