It was impossible for him to locate his pursuers.

They would come together, he decided, and take to his tracks.
What, then, was his surprise and dismay to run out of a thicket right into a low ridge of rough, broken rock, impossible to get a horse over.
He wheeled to the left along its base.

The sandy ground gave place to a harder soil, where his horse did not labor so.

Here the growths of mesquite and cactus became scanter, affording better travel but poor cover.

He kept sharp eyes ahead, and, as he had expected, soon saw moving dust-clouds and the dark figures of horses.