o the outer air.

He shivered as he emerged into the open street. Whether this chill came
from the damp cool of the night or from nervous excitement, he could not
tell. The memory of the whispered warning bore heavily upon his mind.

Turning his face resolutely in the direction of the hotel, he walked
three blocks, then hailed a passing taxi. When the taxi dropped him, a
few minutes later, he was still four blocks from the point of his
destination. Covering this distance with rapid strides, he came to the
rear of the hotel. There, dodging past a line of waiting taxis, he came
at length to a dark corner where a stone bench made an angle with the
wall of a building directly behind the hotel.

Crouching in this corner, he glanced rapidly from right to left to learn
whether or not his arrival had been detected. Satisfied that for the
moment he was safe, he cast a glance upward to where the aerials of the
radiophone glistened in the moonlight. From that point he allowed his
gaze to drop steadily downward until it reached the windows of the
sixteenth floor. There it remained fixed for a full moment.

There came from between his teeth a sudden intake of breath.

Had he seen some movement at the window to the right of the wires that
led to the aerials? He must see, no matter how great the risk.

Drawing a small pair of binoculars from his pocket, he fixed them on the
spot. He then turned a screw at the side of the binocular and suddenly
there appeared upon the wall of the building a round spot of brilliant
light. The size of a plate, this mysterious spot moved rapidly backward
and forward until it at last rested upon the wires by the window.

"Ah!" came in an involuntary whisper from the boy's lips.

A hand, the slender, graceful hand of a girl had been clearly outlined
against the wall. Quickly as it had been withdrawn, Curlie had seen that
between the thumb and finger of that hand was the end of a wire.

"Been tapping the aerial. A girl!" he muttered incredulously. "And it
was she who whispered to me out of the night."

He had been crouching low. Now he rose, stretched himself, pocketed his
instrument and was about to make his way out of the yard when, with the
suddenness of a tiger, a body launched itself upon his back.

So unexpected was the assault that the boy's body closed up like a jack
knife. He fell, face down, completely doubled up, with his face between
his knees.

"Now I got yuh!" was snarled into his e