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.