After living in Haiti for a time, Curlie had found himself once more in the grip of wanderlust. Having returned to New York, he fell in with a friend who was in the Air Mail Service.

“Come with us,” his friend had invited. “Know the thrill of service in the clouds. Join a growing enterprise. Already Uncle Sam’s airplanes each day travel a distance equal to the airline that reaches from Chicago to Cape Town, Africa.”

Curlie had joined up gladly. A natural mechanic, and an aviator with several hundred miles to his credit, he was not long in gaining a place near the first rank of mail pilots.

When one of the regular Air Mail pilots flying from New York had been laid up by a case of nerves following a crackup, Curlie was given the stick. So here he was on his third long flight with fifteen hundred pounds of mail on board, his powerful plane drumming happily through the night.

Happily, but not for long. Scarcely had he passed over the bright lights that shone up from the “Greatest of all Carnivals,” than things began to happen.

The beginning seemed insignificant enough. His keen ears had detected a sound.

“What was that sound?” He had strained his ears in a vain endeavor to distinguish this new beat on his eardrums which had come to disturb him.

Not that there had been no sound before. There was plenty. For hours he had listened to the ceaseless roar of a six hundred horsepower airplane motor. True, this was muffled by a heavy radio head-set pressed lightly against his ears. But it was distinct enough for all that.

And now there had come a second sound. At first faint, indistinct. Then louder. Like bells, motors have their one definite sound and pitch. The experienced airman knows the sound of his own motor and many others.

“It’s a plane,” he told himself. “But at such a time, and such a place!”