Darkness had fallen when I went out to the Camel-back, got in, and started the turbine motor. I rose into the night and flew northward over the starlit mountain wilderness. At last I made out the shape of Mocolynatal ahead, and climbed far above it. I sailed over, and came upon a strange scene. Indeed, the mountain had a crater! Below me was a great bowl, perhaps two miles across, brilliantly lit by rows of electric lights. I made out long lines of buildings--huge structures of sheet iron, gleaming in the light. Toward the south rim seemed to be a landing field, with broad beams of intense light pouring out over the hundreds of red planes lined up across it. North of that was a lake, and I saw scores of red seaplanes moored by brightly lit docks at the edge. There was movement below me. I saw the headlights of moving trucks upon smooth gravel roads about the lake, and there were men at work on the docks and at the landing field. Dense smoke, a luminous white in the glare of the lights, was rising from some of the buildings that must have been factories. The lunatic had indeed made thorough preparation for his planned attack against the world! I cut off the engine of my machine, set the motor to whirling, and dropped silently toward the circle of darkness about the rim of the crater. In fifteen minutes more I had landed it on a bare, rocky slope. I waited a moment, but there was no sign that my coming had been observed, so presently I left the plane, with my automatic in my hand, wishing I knew how to operate the strange weapon in my pocket. I spent several hours slipping about in the shadows among the fallen boulders on the bank of talus about the rim, looking down into the brightly lit crater. At last, I came down in the shadow of an isolated building of gray concrete, with slender masts rising above it--the hidden radio station. In an open space before it, flooded with light, I saw a strange machine. It was like one of the red airplanes, but the closed fuselage was so large that it looked almost like a small dirigible balloon, while the short wings were no larger than those of the ordinary machines. It occurred to me that the "negative-gravity" gas was probably used to lift it. As I stood watching it, I saw a party coming aboard. There were a dozen soldiers, in red uniform. Among them I recognized the short figure of Vars, the maniac, if he was a maniac. And behind him were three closely guarded figures, one of them evidently a woman. Were they my three lost friends? I had every reason to think they were. Vars had promised not to injure Ellen or the Doctor, had implied that he wished to take them with him. I was still watching when I heard a light footstep behind me. I whirled quickly, only to receive the sharp point of a bayonet against my chest. "Drop it!" a sharp voice commanded as I tried to raise my automatic. The pressure back of the keen blade was somewhat increased, and I obeyed.