The Rogan leader, squealing and grimacing, advanced toward the victim on the metal plate. One of the long arms went out and a sucker-disk was pressed to Dex's cheek. Dex quivered at the loathsome contact of that soft and slimy substance; then set his jaws to keep from groaning as the disk was jerked away, to carry with it a fragment of skin and flesh. Gingerly, the tall leader felt the twitching, blackened stump of his blasted arm. Dex grinned mirthlessly at that: he'd struck one or two blows in his own defense, anyhow! At sight of the Earthman's grin, an expression of defiance and grim joy that needed no interpreting to be understandable, the Rogan leader fairly danced with rage. His long arm went out to the switch beside the plate, and pulled it down another notch--just a little, not nearly to the current that had torn at the slave. At the increased torment resulting from that slight movement of the regulating lever, Dex yelled aloud in spite of all his will power. It seemed as though his whole body were about to burst into self-generated flame. Every cell and fiber of him seemed on the verge of flying apart. He could feel his eyes start from his head, could feel every hair on his scalp stand up as though discharging electric sparks. A minute or two of that and he would go mad! He cried out again, and twisted helplessly in his bonds. And then the terrible torture stopped. The Rogan had not touched the switch--yet whatever sort of current it was that charged the plate was abruptly clicked off, as though someone at a distance had cut a wire or thrown a master-switch. * * * * * Simultaneously with its ceasing, an invisible, crushing sea seemed to envelope everything. Dex felt his body sag against his metal bonds as if it had been changed to lead. Before him the Rogans, who had been crowding closer to watch gloatingly each grimace he made, shot doorward as though their pipe-stem legs had been swept from under them. The leader fell on the stump of his seared arm and, a deafening squeal of rage and pain came from his little mouth. His tube fell from his grasp and rolled over the floor half a dozen yards away from him. Amazed, observing the stricken creatures only dimly through a haze of pain, Dex saw them struggle vainly to get up again, and heard them chattering excitedly to themselves. For the moment, in the face of this queer phenomenon, the prisoner seemed to be forgotten. And Dex was quick to seize the momentary advantage. "Greca!" he called. "The tube! There--on the floor!" The girl raised her head quickly, and followed his imploring gaze. Laboriously she started for the tube. At the same instant the Rogan leader began to feel around him for his lost weapon. Not finding it, he raised his head and glanced about for it. He saw the girl making her way toward it and, with a squeak of terror, began to crawl toward it himself. * * * * *