The plane was no longer controllable. True, she responded in some sort to the controls, but all Tommy was able to do was to keep her from going into a crazy sideslip or nose dive as he fought with the elements. And those elements were like a devil unchained. One moment he was dropping like a plummet, the next he was shooting up like a rocket as a vertical blast of air caught the plane and tossed her like a cork into the invisible heavens. Then she was revolving, as if in a maelstrom, and by degrees this rotary movement began to predominate. Round and round went the plane, in circles that gradually narrowed, and it was all Tommy could do to swing the stick so as to keep her from skidding or sideslipping. And as he worked desperately at his task Tommy began to realize something that made him wonder if he was not dreaming. * * * * * The snow was no longer snow, but rain--mist, rather, warm mist that had already cleared the windshield and covered it with tiny drops. And that white, opaque world into which he was looking was no longer snow but fog--the densest fog that Tommy had ever encountered. Fog like white wool, drifting past him in fleecy flakes that looked as if they had solid substance. Warm fog that was like balm upon his frozen skin, but of a warmth that was impossible within a few miles of the frozen pole. Then there came a momentary break in it, and Tommy looked down and uttered a cry of fear. Fear, because he knew that he must be dreaming. Not more than a thousand feet beneath him he saw patches of snow, and patches of--green grass, the brightest and most verdant green that he had ever seen in his life. He turned round at a touch on his shoulder. Dodd was leaning over him, one hand pointing menacingly upward and onward. "You fool," Tommy bellowed in his ear, "d'you think the south pole lies over there? It's here! Yeah, don't you get it, Jimmy? Look down! This valley--God, Jimmy, the south pole's a hole in the ground!" And as he spoke he remembered vaguely some crank who had once insisted that the two poles were hollow because--what was the fellow's reasoning? Tommy could not remember it. But there was no longer any doubt but that they were dropping into a hole. Not more than a mile around, which explained why neither Scott nor Amundsen had found it when they approximated to the site of the pole. A hole--a warm hole, up which a current of warm air was rushing, forming the white mist that now gradually thinned as the plane descended. The plateau with its covering of eternal snows loomed in a white circle high overhead. Underneath was green grass now--grass and trees! * * * * * The fog was nearly gone. The plane responded to the controls again. Tommy pushed the stick forward and came round in a tighter circle.