e began ascending a small hill. At the top of this
was a level patch, thickly overgrown with short brush.

He had just entered the brush when he heard a strange sound. He listened
intently.

"Thet's a hoss in pain," he said to himself. "Too bad if the critter hez
had a tumble an' broke a leg! If that's---- By gum!"

Jack had stumbled upon a large opening directly in the midst of the
brush. Before he could turn back the very soil beneath his feet gave
way, and over and over he rolled down an incline of forty-five degrees,
to bring up at last at the edge of a pool of black water and mud.

Fortunately he was not hurt, although the roll had dazed him and cut
short his wind. As soon as he could he leaped to his feet and gazed
around him.

The horse he had heard lay half in and half out of the mud. Its leg was
caught between two rocks, and it was trying frantically to free itself.
It was his own beast, and at once recognized him.

"Whoa there!" cried Rasco, and did all he could to soothe the animal.
The horse appeared to understand that assistance was at hand, and became
quiet, while Rasco quickly released the locked leg and the beast
floundered up to a safe footing.

"Well, we're in a pocket, 'pears ter me," reflected the man of the
plains as he gazed about him. On three sides the walls of the hole were
very nearly perpendicular, on the fourth the slant was as previously
stated, but here the soil was spongy and treacherous.

"Hang me ef I'm a-goin' ter stay here all day," muttered Rasco, after a
view of the situation. "Come, boy, it's up thet slope or nuthin'," and
he leaped on the horse's back and urged him forward on a run.

Twice did the horse try to ascend to the plain above and fail. Then
Rasco urged him forward a third time. This time the beast balked and
away went the man of the plains over his head.

Fortunately Rasco landed in a tolerably soft spot, otherwise his neck
would surely have been broken. As it was, his head struck the root of a
fallen tree, which had once stood upon the edge of the hole, and he
rolled back near the pool all but senseless.

It was a quarter of an hour later before he felt like stirring again.

"Hang the hoss!" he murmured half aloud, yet, all told, he did not blame
the animal so much for balking. "Couldn't do it, eh, boy?" he said, and
the beast shook his mane knowingly.

"Git along alone, then!" went on Rasco, and struck the horse on the
flank.

Away went the steed, and t