It was a beautiful, unearthly spectacle, with its silence the strangest feature.
But suddenly Wildfire broke that silence with a whistle which to Slone's overstrained faculties seemed a blast as piercing as the splitting sound of lightning.

And with the whistle Wildfire plunged up toward the pass.

Slone yelled at the top of his lungs and fired his gun before he could terrorize the stallion and drive him back down the slope.

Soon Wildfire became again a running black object, and then he disappeared.
The great line of fire had gotten beyond the monuments and now stretched unbroken across the valley from wall to slope.

Wildfire could never pierce that line of flames.