It was that which broke the spell for the two, and they flung themselves toward the great condenser, still yards away, hurled themselves toward the control, the great arms looping toward the staggering two. Ralton heard a cry from Mallett, felt him jerked back from his side by one of those arms, but did not look back even in that instant, flinging himself madly on toward the control. He was within a dozen feet of it, a half-dozen--was almost within reach of it--and then another great glistening arm had looped lightning-like from the masses behind and had caught and held him in its cold grip, while upon him and upon Mallett swept the gleaming floods from which those arms had shot out! Ralton felt that cold, terrific grip about him, pulling him backward, the shining masses behind gliding swiftly upon him, and as they did so he put his last strength into one supreme effort, straining with a final mad burst of strength toward the control-knob just before him. Beneath that super-human effort the relentless grip that held him relaxed a little for an instant, and in that instant Ralton's forward-straining fingers had just touched the control-knob, had flicked it sharply upward from the white letters at which it stood to those just above, from the cosmic ray vibrations to those of the radio-active vibrations. The next instant it seemed to him that over all the world there lay a sudden, tremendous stillness, a complete and utter cessation of all movement and sound, as the grip that held him, the gray masses that had been rushing forward upon him and upon Mallett paused, halted, hesitated. Then, as he swayed there, he felt the grip relax and disappear, saw dazedly that the translucent arm about him had changed oddly, had shriveled suddenly, crumbled into a smear of gray powder that fell to the ground! And the mighty masses behind him, the great tides of protoplasm on the cone's summit and sides, and those he could see out over the island's level sands far below, all had crumbled, too, disintegrated in that same moment, and where they had been was but a thick coating of fine gray powder! Gray powder in the coating of which behind them lay the dark, twisted bodies of Munson and the others! Gray powder that lay, he knew, over all earth where the protoplasm masses had been but a moment before, that lay in city and on land, the sole remaining evidence of the gigantic masses which the great condenser with its concentrated cosmic rays had built up over all earth and which with its concentrated radio-active rays it had in the same way destroyed! Gray powder, that alone remained of the greatest and most terrible menace ever to challenge the existence of man and the world of man!