“You both realize how serious that Sky Spook scare has come to be,” he had whispered. “I wasn’t going to say anything to Chick, because he’s pretty young—” at once Chick had denied the insinuation, “—all right, Chick,” Scott had continued. “Just the same, I wasn’t going to include you—but it may help, at that—if you are ‘game’ and not scarey.”

Assured of Chick’s absolute bravery and perfect gameness the test pilot had suggested that he wanted to “get to the bottom—or top—of the spook business.”

“Ever since the first pilot cracked up,” he had said, “and explained that he thought he saw a spooky-looking crate flying straight at him out of a cloud, I’ve thought he was trying to ‘cover up’ his own carelessness with that story. The next one to see ‘it’ must have caught the scare and had an overdose of imaginittis. But it has gotten into the newspapers and they call the new airport ‘Mystery Airport.’ It’s ruining business for Don McLeod’s uncle, and I’d like to help him out by proving that there isn’t any ghost ship flying in and out of the clouds to make a pass at every pilot whose firm gives the new airport its business.”

Garry had agreed with Scott’s theory that some hidden enemy was trying to ruin the airport’s business, and hamper its growth. Readily he had consented to help Scott with his simple plan, which required that with Scott the two youths would fly, that night, inviting the appearance of the ghostly, or human apparition, at which time Scott felt confident that he could run down the culprit and end the scare before it further harmed the morale of the flying force or resulted in the loss of contracts for air line hangar space and landing and take-off fees.

The eagerness with which Chick had seconded the plan, his pleading to be included in the airplane’s passengers as an observer and signalman, his stout declarations of his complete fearlessness, had suddenly become empty boasts when the three-place ship had reached the vicinity of the swamps adjacent to the airport but not yet drained and prepared for filling in. Eventually the greater part of the swamps would be changed into good ground. Engineers were already preparing to drain away the salt tides flowing in from Long Island Sound and Little Neck Bay. Unless the unexplained mystery of the spectral sky denizen could be settled, it seemed unlikely that the swamp land need ever be reclaimed for airport expansion.

Scott, for years the hangar supervisor and chief test pilot for the airplane construction plant and seaplane base which had existed before the airport project in combination with them had been started, was very anxious, it seemed, to end the ghost scare.

With his two youthful aides, confident Garry and shivering Chick, he made a good descent to the surface of a wide sheet of enclosed, shallow water, let the amphibian craft, which could make either earth or water landings, run out of momentum, and then sat back, loosening his helmet chin straps.

“Here’s the full plan,” he turned around in the cockpit in the dark, salty-smelling marsh, silent except for the plash of a leaping fish or the cry of a gull seeking a belated dinner, “I didn’t want to be seen talking too long at the plant. You never know who ‘might be’—you know!”

“I understand,” admitted Garry. “Let’s hear it all.”

“I went to Don as soon as I left you—and he’s managed to get Mr. McLeod to let him go aloft in the Dart.” He referred to a light, fast two-seater, the personal property of the airport manager, which his seventeen-year-old nephew had secured for the evening. “Now, Don is as good an amateur pilot as you’ll find; but he lacks stunting experience. He will come here, set down, and then I’ll take the Dart and keep it warmed up and ready, while Don, with you two for observers, will go up and cruise around—and invite Mr. Ghost to come at you!”