kle of
the band by means of which the saddle was held firmly on the beast's
back.

Once he had a grip on this he made a sudden pull. Domino squirmed, and
for the moment Bob feared the animal would break away.

"Easy now, old fellow; take it quiet! I'll have that saddle off in a
jiffy; and see what is wrong. Softly, Domino! Good old Domino!"

While he was talking in this manner Bob was releasing the band; and,
with a sudden jerk, he threw the saddle to the ground.

His quick eye detected signs of blood on the glossy back of the
Kentucky horse.

"That's what it was!" he exclaimed, angrily. "A thorn of some kind,
put there so that when I jumped into my seat my weight would drive it
in. And I reckon, too, it would be just like the cowardly sneak to
pick out one that had a poison tip! Oh! what a skunk! and how I'd like
to see some of the boys at the ranch round him up! But I wonder, now
could I find it? I'd like to get Frank's opinion on it."

The horse had by now ceased his mad prancing. This proved that the
cause for his strange actions had been removed when Bob cast the saddle
off. And it did not require a hunt of more than two minutes to
discover some little object clinging to the cloth under the saddle. It
was, just as Bob had suspected, a thorn with several points that were
as sharp as needles, and very tough.

Bob put it away in one of his pockets. Then he once more replaced the
saddle, carefully adjusting the girth so as to avoid any more pressure
on the painful back of Domino than was absolutely necessary.

The horse seemed to understand his master's actions, and, although
still restive, allowed Bob to mount.

Cantering along over the back trail, in half an hour Bob came in sight
of his chum heading toward him.

"Well," said Frank, as they finally met, "I was beginning to get
worried about you, even though I knew you could manage a horse all
right. It was a lively run, I should say," as he glanced at the
foam-streaked flanks of the gloss black.

"As fierce a dash as I ever want to take," answered Bob, patting his
horse gently.

"Did you find out what ailed him?" asked the other.

"After I'd spent some time trying to keep from being thrown, I did."

As he said this Bob drew the thorn from his pocket, and held it before
Frank, who took the vicious little thing in his hand.

"I thought so," he muttered. "That's Peg's idea of getting even with
us; the coward!"

"But you don't mean to