If not as experienced, in point of years, as Scott, the seventeen-year-old junior flyer at the Dart’s controls was as expert. Landings in daylight, night conditions, or in darkness, were easy for Don: because of a season of timidity concerning “getting down,” at the start of his flying practice, the youth had determined to break himself of his timidity before it interfered with his rapid progress. Alone in his uncle’s Dart, he had made practice take-offs and landings in every sort of weather and under all imaginable conditions, until he was so sure of his ship that he had no uneasiness about setting down. He realized that the modern airplane is so well stabilized, so well designed, that it does just what its pilot wants it to do—that in every case where some part has not failed, the pilot’s mental condition and its resulting reaction on the handling of the ship is what makes the difference between safe flying and accidents that result in injury or worse.

The small, wide-winged craft sent out a split crest of foam, coming swiftly closer to the Dragonfly; but it lost speed and Don maneuvered it to a point close alongside the larger craft and with his own wings just a little behind those of the biplane. Gliding up to its stop, the Dart rested quietly in the still, rather murky water.

“Hello!” its pilot greeted the others. “Did I give you a solution of the Mystery of Mystery Airport!”

“You certainly did!” Garry admitted. “Chick thought you were the flying phantom——”

“Just as the first pilot to crash thought some chance ship, lighted up by a flash of some beacon, was the ghost,” Don interrupted.

“I’m not so sure of that,” Scott spoke, taking up the thread of a statement he had been about to make before the Dart came down. “I’ve been interested in the mystery—I like spooks, you know——”

“More than I do!” broke in Chick, gloomily. Scott, laughing, agreed.

“Every fellow to his taste,” he quoted. “Anyhow, I’ve been reading up on ghosts, and talking to some of the ‘old inhabitants’ around the marsh. Want to know what I dug up?”

All three eagerly chorused agreement. “Away back in the days when airplanes were tricky to handle and the pilots knew less about aerodynamics than they do today,” he stated, “a flyer was over this swamp, on just about this sort of night,” he indicated the clustered, slow-moving, fleecy groups of clouds, some assuming the pyramid shape of thunderheads, “one of the clam-diggers at the edge of the swamp recalls it very plainly. He was out at low tide after clams when—it happened!”

“What!” asked Chick, forgetting his uneasiness and the gloomy, spooky environment in his suspense.