For Hal Dane, though, that mere scrape was serious enough. At the shock of the other’s passing blow, the whole monoplane trembled, and went limping on into the night with a bent wing that drooped dangerously.

After fifteen minutes of erratic flying, Hal had to take to ground. The fog had mercifully lifted somewhat. He coaxed the crippled plane on to the edge of a rosy glow that meant a town and landed on the outskirts of this.

Hal spent the rest of the night in trips back and forth from the town, in rousting out mechanics, hunting up tools and repair material, and in repairing the wing by lantern light.

At last he was able to glide up along the airways again. Instead of humming into Denver in mid-morning, as he had planned, it was deep into another night when he finally zoomed into the airport of that Colorado metropolis,—turned his plane over to competent mechanics, and stumbled for sleeping quarters.

Before dawn, he was under way again. This time luck was with him and he did the last thousand-mile lap of his journey in less than nine hours.

As it was, he arrived in San Francisco without even an hour’s space between him and the great Onheim Safety Device try-out. No time for any rest for himself, no time for any preliminary testing of the splendid new gyroscope plane fresh from the skids of the Wiljohn factory. All he could do was give a thorough ground inspection of every part of this strange mechanism of flight that he had conceived, and that the Wiljohn factories had developed with the utmost care. There it stood—short, fixed wings, sturdy, black-enameled body, a silvered whirl of gyroscope wings above the fuselage. The strangest looking creation for flight man had ever invented! Strange looking—yes! But if it worked, it would be man’s most forward step in safe flying!

It was perfect, just as he had planned it, from its geared motor to its curiously flexible wind blades. Exultation filled Hal Dane as he looked on this thing he had created.

It was an exultation that was short-lived though. When he went out to the exhibition grounds and saw the veritable trap that had been built for him to rise from, his heart went cold.

Through misunderstanding of the wording of Colonel Wiljohn’s frantic telegraphic efforts to get all things ready for Hal Dane’s flight demonstration, the Wiljohn workmen had built no platform for the plane to rise from as had been expected. Instead, they had built a sort of tower inclosure out of which the strange new gyroscope was to take its flight.

A white-faced Fuz McGinnis waited for Hal just outside the door of this tower that looked like a death trap. He hadn’t seen Fuz for months now since demonstration flying had taken McGinnis into half the states of the Union on Wiljohn business.