realized that the ground was not slipping by under him as
rapidly as it should. He glanced at his air-speed meter.

"What the dickens?" he cried in surprise. For an hour his speed had
remained almost constant at one hundred miles an hour. Without
apparent cause it had dropped to forty, less than flying speed. He
realized that he was falling. A glance at his altimeter confirmed the
impression. The needle had dropped four hundred feet and was slowly
moving toward sea-level.

* * * * *

With an exclamation of alarm, Purdy advanced his throttle until the
three motors of his plane roared at full capacity. For a moment his
air-speed picked up, but the gain was only momentary. As he watched,
the meter dropped to zero, although the propellers still whirled at
top speed. His altimeter showed that he was gradually losing
elevation.

He stood up and looked over the side of his plane. The ground below
him was stationary as far as forward progress was concerned, but it
was slowly rising to meet him. He fumbled at the release ring of his
parachute but another glance at the ground made him hesitate. It was
not more than three hundred feet below him.

"I must be dreaming!" he cried. The ground was no longer stationary.
For some unexplained reason he was going backward. The motors were
still roaring at top speed. Purdy dropped back into his seat in the
cockpit. With his ailerons set for maximum lift he coaxed every
possible revolution from his laboring motors. For several minutes he
strained at the controls before he cast a quick glance over the side.
His backward speed had accelerated and the ground was less than fifty
feet below him. It was too close for a parachute jump.

"As slow as I'm falling, I won't crack much, anyway," he consoled
himself. He reached for his switch and the roar of the motors died
away in silence. The plane gave a sickening lurch backwards and down
for an instant. Purdy again leaned over the side. He was no longer
going either forward or back but was sinking slowly down. He looked at
the ground directly under him. A cry of horror came from his lips. He
sat back mopping his brow. Another glance over the side brought an
expression of terror to his white face and he reached for the heavy
automatic pistol which hung by the side of the control seat.

* * * * *

"He cleared Bellefonte at nine in the morning, Dr. Bird" said
Inspector Dolan of the