Except upward. We tried higher altitudes. The air was purer up there, but also it was thinner, and we could not live in it for any length of time. Nor could we sustain ourselves aloft indefinitely—to say nothing of sleeping and eating. Once in desperation we tried swimming off the meteor into Space. But the lack of any breathable air at all soon brought us struggling downward. That night there was a gentle wind. The breath of the fire-monster swept up over the horizon and came upon us with a deadly blast. We woke up, choking. It was daylight, with a small red-yellow sun dim and blurred by the poisonous haze that enveloped us. Nona was crying. But suddenly I laughed, triumphantly, for I realized now that the fire-monster could not harm us. We were lying at the river bank. I seized Nona in my arms and flung her headlong downward into the water. And I plunged in after her. The water here was deep—thirty feet perhaps, as you on Earth would measure it. With arms flying, we sank like stones to the river bottom. CHAPTER VII I was presently breathing the water with fair normality. Indeed, after the noxious air we had been struggling with so long, it came almost as a relief. Nona’s arms were about my neck; I loosed them, but she clung to my hand. Together we tried to stand upright. This river bottom seemed a gray sand. But we could not maintain footing. The water was empty—by which I mean there was no marine vegetation here—nothing that we could grip with our hands. And from behind us, the current wafted us gently but irresistibly forward. I soon discovered that normally we would float in an upright position. We held ourselves so with our toes occasionally touching the soil, bouncing along like feathers in a gentle breeze. The scene around us now more resembled a misty gray day on one of our sandy Earth-deserts than anything else I can call to mind. The ground was undulating gray sand, sloping upward to one side, and with a steady incline downward in front. And down this slope we were blowing. Swim, you say? It never occurred to either of us! We were frightened; we clung to each other, striving to remain upright. Very soon the light from overhead seemed to deepen. But other light—the diffused light inherent to the water itself—grew brighter by contrast. We were swept forward much faster—and down a much steeper hill. I know now that the change was caused by the river having plunged into that cliff-face, to become subterranean. How far we were carried I cannot say. A mile perhaps. Or more. Rocky cliffs now seemed to pen us in; it was as though we were in a steep canyon, with a powerful wind driving us down through it.