His head came against the leg of a bench. For a few moments he was dazed. But it seemed only a few seconds to him before he had staggered to his feet, rubbing his bruised head. Anxiously, he peered about the room. The machine-monster and Agnes were gone! He stumbled back to the mass of apparatus in the center of the huge laboratory. Intently, he gazed into the upright pillar of crimson flame. Nothing was visible there. "No, the other!" he gasped. "The violet is the way they went." * * * * * He turned to the companion ray of violet radiance that beat straight down on the opposite side of the tiny, whirling planet. And in that motionless torrent of chill violet flame he saw them. Tiny, already, and swiftly dwindling! With green wings outspread, the machine-monster was beating swiftly upward through the pillar of purple-blue flame. And close against the crystal tube that contained its brain, was Agnes, held fast by the whip-like tentacles of glistening green metal. Larry moved to spring after them, into the torrent of violet light. But sudden caution restrained him. "I'd shrink, too!" he muttered. "And then where would I be? I'd be standing on the glass platform, I guess. And the thing flying off over my head!" He gazed at the rapidly dwindling forms of Agnes Sterling and her amazing abductor. As it grew smaller, the machine-monster flew higher in the violet beam, until it was opposite the tiny, spinning planet. The distance between the red and the violet rays was just slightly more than the diameter of the pygmy world. The sphere hung between them, one side of it a fraction of an inch from the red, the other as near the violet. Opposite the elfin planet, the monster ceased to climb. It hung there in the violet ray, an inch from the surface of the little world. And still it swiftly dwindled. It was no larger than a fly, and Larry could barely distinguish the form of the girl, helpless in the green tentacles. Soon she and the monster became a mere greenish speck.... Suddenly they were gone. * * * * * For a little time he stood watching the point where they had vanished, watching the red and the violet rays that poured straight down upon the crystal disks, watching the tiny, green-blue planet spinning so steadily between the bright rays. Abruptly, he recovered from his fascination of wonder. "What did she say?" he muttered. "Something about the monsters carrying off people to sacrifice to a rusty machine that they worship as a god! It took her--for that!" He clenched his fists; his lips became a straight line of determination. "Then I guess we try a voyage in the little plane. A slim chance, maybe. But decidedly better than none!"