He decided to do so.
The hurly-burly was bewildering.

The cattle were bellowing in affright, galloping frenziedly before the two horsemen, dashing back and forth among them at the rear like two lunatics, and goading them to desperate haste.
At the instant the Indian whom Grizzly Weber selected as his man eluded his fatal aim, his horse was running diagonally.

This could not be continued without the abandonment of the herd.

He must wheel, to come back behind the fleeing cattle.

The rancher waited for that moment, prepared to fire the instant any tangible part of the body of the rogue was revealed by the moonlight.
But an astonishing exploit prevented the shot.