rang out, and the party started off after the
Yaquis.

Nort and Dick, riding beside Bud, toward the rear of the cavalcade,
looked down to see what the "sign" consisted of. Aside from some hoof
marks in the earth they saw nothing.

"They might have been made by our own ponies," observed Nort.

"Yes, but they weren't," Bud declared.

"How can they tell?" asked Dick.

"Oh, I don't know exactly, but there are dozens of little points that
an Indian trailer looks for," Bud answered. "He can tell whether the
horses trotted or walked. He can tell whether the man who rode him was
a tenderfoot or a cowpuncher. And of course it's easy enough to tell
in which direction a horse is going."

"Unless they put the shoes on backwards," said Nort.

"There isn't much of that done," said Bud. "And, as a matter of fact,
as you know, they don't shoe many horses out here. They let 'em run
barefoot. Anyhow, it looks as though we really were on the trail of
the Yaquis at last."

"I hope so!" agreed Nort and Dick.

CHAPTER XVII

AN ALARM

While the boy ranchers and their friends from Diamond X had joined
forces with Uncle Sam's troopers and were warm on the trail of the
Yaquis, the squalid, degenerate and vicious band that had captured
Rosemary and Floyd still retained possession of their captives. Though
disheartened and apprehensive, Rosemary and her brother had made up
their minds to one thing--they would not be separated--come what might.

For his sister's sake Floyd had firmly decided that if they attempted
to take Rosemary off by herself he would, at any cost, make an effort
to follow, even if it resulted in his death at the hands of the Indians.

As for Rosemary, she had but one thought--to remain near her brother at
any cost. And as she had so far managed to conceal from the Yaquis the
fact that she possessed her efficient automatic, and a supply of
ammunition, she felt a sense of security that otherwise would not have
been with her. She, too, resolved on desperate measures before she
would let them separate her and Floyd.

So when Mike, as the one who carried out the orders of his villainous
chief Paz, tried to take Rosemary off by herself, probably to break her
spirit and induce her to send a letter to her friends asking that
ransom money be forwarded--when Mike tried to do this he received one
of the surprises of his miserable life as he found himself looking into
the muzzle of Rosemary's gun.

"Ugh!