owboys. Tommy declares to this day that he felt the hair rising
straight up on his head when he realized that he was talking with one of
the hold-up men. He also says that his teeth chattered with fright.

"The last we heard of the cowboys," he answered, "they were going
straight north. I thought you went that way, too," he added.

"We couldn't get too far away from our base of supplies," replied the
other with a cynical laugh. "We were just thinking of going back to your
camp for a square meal when we heard you blundering up the slope. You'll
have to feed us for a few days, young fellow!"

CHAPTER V

A DETECTIVE AND A ROBBER

Half way back to the camp, Sandy crouched down at the sound of
approaching footsteps.

"I'll bet that's Tommy trying to give me a scare," was the boy's
thought.

He listened intently for a moment, without hearing a repetition of the
noise, and started on again.

"If I thought that really was Tommy," he mused, "I'd arrange a neat
little surprise for him. He's always up to his tricks."

The sound of heavy breathing came to his ears directly, and, not having
the least doubt that the approaching figure was that of his chum, he
waited for an instant until the labored breathing seemed to be passing
the spot where he stood and leaped forward.

Much to his amazement he struck a pair of broad, muscular shoulders
instead of the slender shoulders of his chum and felt himself in the
grasp of a pair of powerful hands.

"What are you prowling around in the night for?" was asked.

Sandy pulled away at the hand which was smothering him and taking the
hint, his captor released him for a moment.

"I can't talk with my mouth and nose all stopped up!" returned the boy.
"What did you want to go and do that for?"

"What are you prowling about in the night for?" repeated the other.

Sandy thought he recognized the voice as that of Katz, the plain-clothes
policeman who had lied on the previous evening regarding his residence
and his calling.

"I might ask the same of you," replied Sandy, mopping his face with his
handkerchief. "What are you prowling around for?"

"Keeping an eye on your camp," replied the other gruffly.

"What for?" demanded Sandy.

"Because you're suspicious characters."

"You're Katz, aren't you?" asked Sandy.

"Who told you that?" snarled the other.

"John Johnson," was the reply.

"I recognized him as one of Horton's men," declared Katz.

"That's what he is!" Sa