nature to surrender a cause so
long as one spark of hope of success remained.

The mountain trail now led downward for a few hundred yards, and then
wound through a rocky pass, dark and forbidding. Allen kept watch on
either side for a possible ambush, but none presented itself.

"He has gone on, that is certain," he thought. "I rather guess he thinks
to tire me out, knowing the condition my mare is in; but if he thinks
that he is mistaken. I'll follow, if I have to do it on foot."

At last the trail left the rocky pass and came out upon some shelving
rocks overlooking a deep canyon, at the bottom of which sparkled the
swift-running stream. Here a rude bridge led to the other side, a bridge
composed of slender trees and rough-hewn planks.

Without hesitation, Allen rode upon the bridge. As he did so a derisive
laugh resounded from the other side of the canyon, and he saw the man he
was after and two others ride into view.

Then, before he could turn back, Allen felt the bridge sagging beneath
him. Suddenly it parted in the center, and horse and youth went plunging
headlong toward the waters far beneath.

CHAPTER IV.

The Man in the Sink Hole

We will now return to the ranch and see how Chet and Paul were faring
during their elder brother's absence.

Chet took the string of fish, and selecting two, began to clean them. He
was used to the work, and did it with a dexterity and quickness that
could not have been excelled. Ever since his mother had died it had
fallen upon Chet's young shoulders to do the culinary work about the
ranch home.

While Chet was thus engaged Paul busied himself in looking over the
shotguns, cleaning and oiling them and then loading up.

The fish cooked, Chet set the table, putting on three plates, although
he himself was almost certain Allen would not come back in time for the
meal.

"It's queer, I've been thinking," remarked Paul, during the progress of
the meal, "Allen said nothing about the result of his morning trip."

"He was too excited over the theft of the horses to think of anything
else, I reckon," was the reply Chet made. "It was enough to upset any
one's mind."

"At least he might have said if he had heard from Uncle Barnaby,"
grumbled Paul. "More particularly, as we were just dying to know."

"I imagine if he had heard he would have said so and left us the letter,
Paul. Allen knows as well as you or I how anxious we really were."

"It's queer the way Uncle