I finished with the wall. There was a twenty-foot square piece of metal apparatus, ramified and intricate; I heaved it over upon its side. A thousand little mirrors and prisms, dislodged from it, came out in a splintering deluge. I was aware of Snap fighting with a brown-shelled figure. Then he was free of it. I saw it mashed and broken at his feet as I dove past, swimming in the smoke to lunge the length of a great fluorescent tube which was still dimly glowing. My pole pried it over; it crashed with a brief puff of light and the rush of an explosion as air went into its vacuum. I found Snap panting beside me, clinging to me in mid-air. The glare was dying around us; the din was lessening. We were choking in the chemical fumes of the released, half-burned gases. Turgid darkness was coming to the wrecked room, with little hissing flares spitting through it. "Enough, Gregg! Listen! Up overhead...." A great siren from up there was screaming into the night. Snap panted, "Got to get out of here. Can't breathe." Together we lunged for the tunnel by which we had entered. I stood a moment, gazing back upon the strewn and scattered room. The delicate nerve-center of Wandl. Heavy green-black gas fumes swirled in it; darkness and silence closed down. 16 Over us was turmoil, that screaming siren. Then suddenly it was checked and we heard the thump and swish of what on Earth would have been called running footsteps and shouts. Snap shoved me. "Don't stay there, you fool!" We lunged up the passage. Figures barred it but they scattered; a bolt hissed at us, but missed. At the kiosk a group of workers and several peering little brains leaped away in terror to let us pass. We gained the open air. With the small gravity rays darting down with repulsion upon the rocks we mounted like rockets out of the cauldron. The upper plateau lay silent in the starlight, but the cauldron behind us was ringing with alarm, and again the danger siren was blaring. I changed my way of direction, swung it to the plateau rocks ahead. The arc of my flight was sharply bent as I went hurtling down. Over me, I saw Snap use the same tactics. I tried to aim for where we had left the girls and Molo. I could not see them down there amid the starlit crags; and suddenly a wild apprehension filled me. How had we dared leave them to Molo's trickery? Then, ahead and below me, I saw the slight figure of one of the girls, standing on a rock with arms outstretched to signal us. I changed my ray to repulsion barely in time to avoid crashing. The landing flung me in a heap. Twenty feet away, Snap came whirling down. We picked ourselves up, saw Anita waving from the rock, and bounded to her. The girls were safe. Venza sat intent, with unwavering watchful gaze across the intervening space to where Molo had flattened himself against his rock, not daring to move. "Still got him," Venza exulted. "He wasn't willing to take any chances with us. You did it, Snap?"