the two contestants rushed on. Suddenly one of Ding-dong's feet caught in a rock, and at the impetus he had attained, the sudden shock caused him to soar upward into the air, as if he were about to essay a flight through space.

Extending his arms spread-eagle fashion, the fleshy, stuttering youth floundered above the ground for a brief second, and then, as Joe dashed across the line he came down with a resounding crash. Flat on his face he fell in the middle of the dusty road.

"Pick him up," exclaimed Nat as he saw the catastrophe.

Joe, who had by this time checked his speed, headed about after Nat, and started for the recumbent Ding-dong. As they neared his side, however, the lad jumped up with a grin on his rotund features.

"Fooled you, didn't I?" he chuckled.

"Goo—d gracious. I thought you had fractured every bone in your body," exclaimed Nat.

"Can't hurt me; I'm made of cast-iron," snickered Ding-dong.

"I always knew that applied to your head," said Joe, determined to tease the boy a bit in revenge for the fright he had given them, "but I never realized before that the complaint had spread all over you."

"I'd have won the race anyhow if I hadn't taken that tumble," retorted Ding-dong, and as this seemed to be no more than the truth the others had nothing to say in rejoinder.

"I guess we had better be getting back to the hotel," said Nat, "we want to get an early start to-morrow, so a good night's sleep will be in order."

But the words were hardly out of his mouth before he stopped short.

The boy had heard voices, apparently coming from the air above them. He soon realized, however, that in reality the speakers were on the mountain-side above them. In fact, he now saw that a trail cut into the road above the point at which they stood. In their dash down the hill they had not noticed it. The other lads, who had also heard the voices, needed no comment to remain quiet.

While they stood listening a figure appeared on the trail, walking rapidly down it. As the newcomer drew closer the boys recognized the features and tall, ungainly outline of the man with the black mustache—"Alkali Ike." He came forward as if with a definite purpose in mind. Evidently, he was not, like the boys, out for a moonlight stroll.

As he approached he stopped and listened intently. Then he gave a low, peculiar whistle. It was like the call of a night bird.

Instantly, from the hill-side above them they heard the signal—for such it seemed—replied to.

At the same instant whoever was on the hillside above began to advance downward. The boys, crouching back in a patch of shadow behind a chaparral clump, could hear the slipping and sliding of their horses' hoofs as they came down the rocky pathway.