Bob was on the ground immediately. His horse was trembling with excitement and other causes. Bob continued to pat him gently, and speak soothing words. All the time he was working toward the buckle 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.