When disposed to become too drowsy, a sudden giving away at the knees recalled him so vigorously, that it was a considerable time before the drowsiness crept over him again.
Thus the night advanced, until all at once, Fred aroused himself as if a sharp pin had been thrust in him.
"By George! I heard something then!" he exclaimed, in an excited undertone, looking sharply about him; "but I don't know where it came from." His impression was that it came from some point directly before him out on the open space; but the most rigid scrutiny failed to reveal the cause.

There was the level stretch of grass, unbroken by stone or shrub, but nothing that could be tortured into the remotest resemblance to a human figure.
"It can't be there," he muttered; "or if it was, it do n't amount--" His senses were aroused to the highest pitch, and he was all attention.
Just as the thoughts were running through his head, he caught the slightest possible rustle from some point behind him.

He turned his head like lightning, and looked and listened.

He could dimly discern the open moonlit space to which reference has already been made; but the intervening trees and undergrowth prevented anything like a satisfactory view.
"There's where it seemed to come from," he said, to himself; "and yet I do n't see how an Indian could have got there without our finding it out.

Maybe it was n't anything, after all." He waited and listened awhile longer, but no more.