“Quite snug, thank you.”
Austin kept the plane climbing steadily until the altitude meter registered twenty thousand feet, then he leveled off for the air was less dense near the ceiling, set his course for Belize, and settled down for the long run to British Honduras. Presently they were soaring through clear skies, but the fog rolled in thick waves and billows beneath them.
“I say, Buddy, change places with me and you can get at those lessons again. I got in some extra licks last night on my stuff,” Bob proposed.
“Very well.” Presently they had changed places and Austin got out his book and note papers. The plane was sailing smoothly and although the fog reached almost up to them at times, the job of piloting was comparatively easy and the boy thought, with an amused smile, of Don Haurea and his men back in the laboratory. When he returned home he would see records of the flight, and furthermore, he would probably be able to tell just how dangerous Lieutenant Morrow had been and exactly why that plane in Havana had shown so much interest in their arrival at Cuba. In a short while the boy was completely absorbed in what he was reading and it wasn’t until Bob pressed his foot vigorously that his attention was called back to the present.
“I say, there’s something rotten about the “Lark”. She’s been flying rather heavy, and—what in the name of Sampson’s donkey is that smell?” Jim glanced at the board and at the same time sniffed cautiously. There was a faint, unfamiliar odor about the tiny cabin, but it was more like the heavy fragrance of too many flowers than anything decaying.
“It’s queer. I’ll lift the roof.” He dropped his work under the seat, unlatched the covering and swung it back. “We haven’t needed that thing, and might have put it up when we got out of the rain.”
“Yes. Suppose that smell is from tropical plants?”
“Good heavens, how could it be?” Austin picked up the tube to speak with his father, if the man were awake, and as he did so his eyes fell on the reflection globe in which he could see the rear of the plane. The end of the tube dropped from his hand, his lower jaw sagged, and he choked in horror. Bob looked at him quickly.
“What is it, old man?”
“Good God, look.” He pointed to the mirror, but the range of Bob’s vision was different, so he turned his head. What he saw left him perfectly speechless. All unconscious that he was being observed, some one was crawling out of the rear cock-pit. Someone who looked more like a monkey than a man, and as he clung to the rim, he secured the transparent cover of the cock-pit.