He headed in that direction, and then saw that the objects were moving towards him.
"They can't be buildings, for buildings don't move like that," he mused.
"Must be cattle, or horses.

Cattle, most likely." To avoid the cattle, he turned slightly southward.

But the animals kept coming closer, and now he saw that they were running in something of a semicircle.
"Can anything be wrong with them ?" he asked himself, and watched the approaching herd with interest.

The bronco, too, pricked up his ears, and gave a sudden snort of alarm.
Then to Dave's ears came the thunder of the herd's hoofs, and he saw that the cattle were on a mad run.

He drew rein and stood up in his stirrups.
The sight that met his gaze was truly alarming.