He knew that it was made by footfalls, and he knew, too, that in the wilderness everyone is an enemy until he is proved to be a friend.

They were in the densest of the undergrowth, and thought and action came to him on the heels of each other, swift as lightning.
"Sink down, Paul! Sink down!" he cried, and grasping his comrade by the shoulder he bore him down among the thick bushes, going down with him.
"Don't move for your life!" he whispered.

"Men are about to pass and they cannot be our kind!" Paul at once became as still as death.

He too under the strain of the wilderness life and the need of caring for oneself was becoming wonderfully acute of the senses and ready of action.

The two boys crouched close together, their heads below the tops of the bushes, although they could see between the leaves and twigs, and neither moved a hair.
Almost hidden in the foliage a line of Indian warriors, like dusky phantoms, passed, in single file, and apparently stepping in one another's tracks.