tently, Buck's face a
curious mixture of alertness and surprise. Up to this moment he had taken
the whole business rather casually, with small expectation that anything
would come of it, but the sound of that shot changed everything. Something
was happening, then, after all--something sinister, perhaps, and certainly
not far away. His eyes narrowed, and when no other sound followed that
single report, he loosed his reins and urged the roan to a gallop.

For perhaps half a mile the two plunged forward amidst a silence that was
broken only by the dull thudding of their horses' hoofs and their own
rapid breathing. Then all at once Buck jerked his roan to a standstill.

"Some one's coming," he warned briefly.

Straight ahead of them the moonlight lay across the flat, rolling prairie
almost like a pathway of molten silver. On either side of the brilliant
stretch the light merged gradually and imperceptibly into shadows--shadows
which yet held a curious, half-luminous quality, giving a sense of
shifting horizons and lending a touch of mystery to the vague distances
which seemed to be revealed.

From somewhere in that illusive shadow land came the faint beat of a
horse's hoofs, growing steadily louder. Eyes narrowed to mere slits,
Stratton stared ahead intently until of a sudden his gaze focused on a
faintly visible moving shape.

He straightened, his right hand falling to the butt of his Colt. But
presently his grip relaxed and he reached out slowly for his rope.

"There's no one on him," he murmured in surprise.

Without turning his head, Jessup made an odd, throaty sound of
acquiescence.

"He's saddled, though," he muttered a moment later, and also began taking
down his rope.

Straight toward them along that moonlit pathway came the flying horse,
head down, stirrups of the empty saddle flapping. Buck held his rope
ready, and when the animal was about a hundred feet away he spurred
suddenly to the right, whirling the widening loop above his head. As it
fell accurately about the horse's neck the animal stopped short with the
mechanical abruptness of the well-trained range mount and stood still,
panting.

Slipping to the ground, Bud ran toward him, with Stratton close behind.
The strange cayuse, a sorrel of medium size, was covered with foam and
lather, and as Jessup came close to him he rolled his eyes in a frightened
manner.

"It's Rick's saddle," said Bud in an agitated tone, after he had made a
hasty examinat