They had considered it worth fifteen hundred a week, though, to fly across these fifteen miles into Mexico and back again.

Johnny shook his head slowly, gave up the puzzle, and took out his wallet to count the money again.
Half an hour he spent, fingering those bank notes, gloating over them, wondering what Mary V would say if she knew he had them, wishing he had another fifteen hundred, so he could pay old Sudden and be done with it.

An unpleasant thought came to him and nagged at him, though he tried to push it from him; the thought that it would be Sudden's security that he would be risking--that the Thunder Bird was not really his until he had paid that note.
The thought troubled him.

He got up and moved restlessly along the base of the towering rock, when something whined past his ear and spatted against a bowlder beyond.

Johnny did not think; he acted instinctively, dropping as though he had been shot and lying there until he had time to plan his next move.