"Coming too, young man?" Sherbrand said, glancing back and smiling. The boy nodded in answer, and thence-forward kept close at the heels of the men, his ears industriously drinking in their conversation, while his eyes were glued on the brown leather satchel depending from the German’s gloved left hand. Both men, now leaning over the side of the pilot’s cockpit, examined the gearing of the hoverer, protected by a transparent casing set in the tough ash, copper-riveted planking of the fuselage. Then with the aid of sulky Davis they tilted the Bird, and inspected the pair of thin circular plates of toughened steel with flanged edges that, revolving at high velocity in different. directions, constituted the horizontal screw. "Driven from the engine, as you see, by an endless chain-drive arrangement. By manipulation of levers, you can throw the tractor out of gear, and hover, under favourable circumstances and in still weather, by means of the horizontal screw alone. But as a rule you keep the tractor working, and the screw acts in one as a lifter and floating-anchor. That’s about all it amounts to!—I’ve said I don’t pretend to hang immovable in the air like the albatross and the condor, not to mention the gull and sparrow-hawk and dragon-fly! While I hover I am making way—but way to an inappreciable amount. One of these days we shall find out the big Secret of Stability. Until then we must rub along as best we can!" Von Herrnung returned: "I am hellishly interested in your invention. It now occurs to me that as you happen to know my flying record"—he shrugged his great shoulders and smoothed his tight red roll of moustache with a well-manicured finger-tip—"that it is possible you would have sufficient confidence to allow me to test your gyroscopic hoverer myself?" He laughed again pleasantly as he finished: "Whatever else I may do, I give you my word of honour I shall not pile up your machine. Will you consent? It may lead—supposing you do not close with the French offer—to big business—done with my friends!" Sherbrand had looked doubtful, only for an instant. Before the twelve-year-old eavesdropper had recovered from the shock that had set his brain spinning and his heart thumping, the situation had been accepted by the owner of the Bird of War. He held out his left hand, and von Herrnung gripped and wrenched it, noting with inward amusement that his grip had brought fresh lines of blood creeping about the edges of Sherbrand’s finger-nails. "You shake hands with the left," he commented, smiling. "Not for the first time have I noticed the peculiarity in Englishmen of the younger breed." "It is a custom," Sherbrand answered, "with—members of an organisation to which I had, and still have, the honour to belong."