open forest. Again he urged his horse, leaving to her keen senses alone the choosing of the path between the great tree trunks. He rode almost in silence. The deep carpet of pine needles, wet from the recent rains, dulled the sound of the horse's hoofs.
Then he heard Snowbird fire for the fourth time; and he knew that he had almost overtaken her. The report seemed to smash the air. And he lashed his horse into the fastest run she knew,—a wild, sobbing figure in the darkness.
"She's only got one shot more," he said. He knew how many bullets her pistol carried; and the danger—whatever it was—must be just at hand. Underbrush cracked beneath him. And then the horse drew up with a jerk that almost hurled him from the saddle.
He lashed at her in vain. She was not afraid of the darkness and the rocks of the trail, but some Terror in the woods in front had in an instant broken his control over her. She reared, snorting; then danced in an impotent circle. Meanwhile, precious seconds were fleeing.
He understood now. The horse stood still, shivering beneath him, but would not advance a step. The silence deepened. Somewhere in the darkness before him a great cougar was waiting by the trail, and Snowbird, hoping for
