."

Tad paused abruptly. A pebble had rattled down the rocky wall and
bounded off some yards to the front of them. Silver Face started and
would have bounded away had not a firm hand been at that instant laid
on the bridle rein.

To one unaccustomed to the mountains the incident might have passed
unnoticed. By this time Tad Butler was a pretty keen woodsman as well
as plainsman. He had learned to take notice of everything. Even the
most trivial signs hold a meaning all their own for the man who
habitually lives close to Nature.

The lad glanced sharply at the rocks.

"See anything?" asked Walter.

"No."

"What did you think you heard?"

"I didn't hear anything but that pebble. The horses smelled something,
though."

While he was speaking the lad's glances were traveling slowly over the
rocks above. All at once he paused.

"Don't stir, Walt. Look up."

"Where?"

"In line with that cloud that looks like a dragon. Then lower your
glance slowly. I think you will see something worth while."

It was a full moment before Walter Perkins discovered that to which
his attention had been called.

"It's a cat," breathed Walt, almost in awe.

"Yes, that's a lion. He is evidently hiding up there, where he has gone
to get away from the dogs. We will walk away a bit as if we were
leaving. Then we'll tether the horses securely. Don't act as if you
saw the beast. I know now what was the matter with the mustangs. They
scented that beast up there."

The ponies were quickly secured, after which the boys crouched in the
brush and sought out the lion again. He was still in the same place,
but was now standing erect, head toward them, well raised as if in a
listening attitude.

"My, isn't he a fine one!" whispered Walt. Walter Perkins was not
suffering from the same complaint that Chunky had caught when he first
saw his lion over in the other canyon, an offshoot from the Bright
Angel Canyon, and where he had lost his rifle so mysteriously.

"Take careful aim; then, when he turns his side toward us, let him
have it," directed Tad.

"Oh, no, you discovered him. He is your game. You shoot, Tad."

Butler shook his head.

"I want you to shoot. I have already killed a cougar. This is your
chance to distinguish yourself."

Walter's eyes sparkled. He raised his rifle, leveling it through the
crotch of a small tree.

"Wait till he turns," whispered Tad, fingering his own rifle anxiously.
He could ha