of a salute when he saw he had to deal with one of his
own kind, and asked:

"Who are you and what are you doing?"

"We're from Diamond X ranch," replied Snake, "and we're on the trail of
the Yaquis who have captured some of our friends!"

"Oh, the Yaquis!" exclaimed the trooper, in evident surprise. "Why,
we're after the same bloody beggars! Glad to have met you. We seem to
be off the trail for some reason. Captain Marshal will want to speak
to you. Better come with me."

"Wait 'til I get my horse," murmured Snake, for, like all westerners,
he hated to take more than a few steps out of the saddle.

A moment later he was riding toward the officers of Uncle Sam's
troopers, while the remainder of the lancers riding in, mingled with
the small force from Diamond X.

"It's good to see you fellows!" chuckled Bud as the bronze-faced
soldiers gathered around the boy ranchers.

"We were just about to open fire on you," said one of the lancers, and
Nort and Dick noticed that in addition to the steel-tipped weapon each
trooper carried a carbine and wore a revolver in his belt. The lances
were, in reality, more for show than for actual use, though in charging
the hostile Indians the spears had served many a useful purpose.

"Glad you didn't," said Yellin' Kid. "There'd have been trouble, for
we were all primed for you," and he waved his hand toward the rocks
amid which some cowboys were just arising, picking up the ammunition
they had spread out for quick use.

"We thought you were Yaquis, and we had orders to shoot to kill,"
explained another trooper.

"And we took you for Indians--not exactly Yaquis, for they don't carry
lances," said Dick. "I'm glad it was a mistake all around."

"But say, do you fellows know anything about these dirty Mexicans who
have crossed the border?" asked a third trooper, a lieutenant from his
stripes, it would appear. "I won't call 'em Indians, though I reckon
they are, of a sort. But where are they? We got orders to take after
'em, but we can't get sight of so much as a dirty blanket."

"Well, we think we're on their trail," Bud answered, "though maybe we
are as far off as you are. Anyhow--"

But he did not complete the sentence. From the distance a single shot
rang out, and as all turned they saw, standing on the sharp horizon
line, a solitary figure, from near which arose a thin wisp of smoke.

CHAPTER XVI

INDIAN "SIGN"

"What's that?" cried Snake, turning from