Sometimes plunging shoulder deep into some treacherous hollow, sometimes guiding the tired horse across the surface frozen over unknown depths.

He had been drinking hard for some days, and, now the excitement of action had gone off, was fearfully nervous.

The snow-glint had dizzied his head, too, and he began to see strange shapes forming themselves in the shade of each hollow, and start at each stumble of his horse.
A swift-flying shadow upon the snow, and a rush of wings overhead.

An eagle.

The lordly scavenger is following him, impatient for him to drop and become a prey.