He stared again at the bell-shape towering above him, but its purpose was beyond guessing: it was a part of the machine. His eyes came back to the mechanism itself. There was a splinter of stone.... Garry reached for it unthinkingly, but his hand was checked in mid-air. The fragment was wedged beneath a tiny lever, holding it erect. "That's the answer," Garry whispered. "The machine was left open,"--he felt of the cover that had been dented by some heavy blow, and saw sharp splinters of rock beneath his feet--"a rock fell from the roof, flaked off and dropped onto the machine, and a splinter jammed this little lever. But the machine has been ticking along...." His fingers reached for the stone. "Let's go!" he said, and grinned broadly at the thoughts that were in his mind. "Let's see what the machine would have done!" The fragment came away within his hand, and he saw the lever fall slowly. There was motion within the case--wheels and shining spheres that touched one upon another were spinning in gleaming circles of silvery green--and from above he heard the first faint whisper of a sound. It came from the bell, and Garry drew back to stare upward. The first soft humming of the clear bell-note was incredibly sweet. It rose in pitch while the volume increased, till the musical note was lost in the rising roar that resounded from walls and roof. Higher it rose; it was a scream that was human in its agony, prodigious in its volume! * * * * * Garry Connell stood trembling with unnamed fear. This sound was unbearable; it beat upon his ears; it battered his whole body; it searched out every quivering nerve and tore at it with fingers of fire. Still higher!--and the scream was piercing and torturing his brain. He felt the jerk of uncontrollable muscles. The whirling machine was a blur of light, and he longed with every fibre of his tortured mind to throw himself upon it--into it!--anything to end the unbearable impact from on high. His body, assailed by a clamor that was physical torment, could not move; the vibrations beat him down with crushing force, while the shrieking voice rose higher, then grew faint, and, with a final whisper, died to nothingness. And still Garry felt himself sinking; the room was blurred; the excruciating agony of tortured nerves melted into a lethargy that swept through him. Dimly he sensed that the monstrous, quivering, bell-topped thing was still launching its devastating rain of vibrations; they were above the range of hearing; but he felt his body quivering in response to the unheard note. Then even these vague fragments of understanding left him. The towering, soundless thing was indistinct ... it vanished in the darkness that closed about....