Here, in the gloom and weirdness of the grotto, the crimson chattering things seemed to gain reality. My imagination perhaps. I do not know. But when once we entered the tunnel, I was newly conscious of them. As though this were their home--their very breeding place. Or perhaps, their jail, where they were held imprisoned--sullen, resentful, watchful of any chance to escape. All fancy, yet as I was soon to learn, it had a very real basis of fact. My fancy was oversharp; my nerves taut. An insect loitered idle against the burnished tunnel-wall; a purple ball of light was over it. I fancied the thing tensed itself as though to spring upon me. I did not breathe again until we were past it. A scientist was leading us now. Freddie, Dan, myself and father--we had left the girls at home. We came to the barred entrance to a room. Its heavy metal door suggested the circular door to a vault in a New York bank. Nothing flimsy here; solid metal, everywhere. My heart sank. Kean had said that with our great physical strength we might be able to force our way in; it did not seem very reasonable. A scientist met us. He smiled gravely at father--a short, slim man, garbed in smooth, dull black. His white hair was clipped close; heavy bull's-eye goggles made his face grotesque. His ears were clasped with a device in appearance not unlike a radio headphone; he removed it, stepping over its dangling wires as he laid it aside. "Come in," said father softly to us. "This is the control room. I wanted you to see it." A low, black-vaulted room. I could see nothing but a small railed area on a two-foot metal platform in the room's center. Within this low metal railing, on a bare flooring of burnished metal, two small mechanisms stood side by side. Two transparent globes, each about a foot in diameter. Within one, a fluorescence of purple; the other held a crimson glow. Wires connected them to near-by batteries; wires ran to a bank of indicators--dials and pressure gauges. Above the neck of each globe, fastened to it, was a small grid of wire; from one, a vague, violet-purple beam streamed out; and from the other, the beam was crimson. I could barely see the scientist as he moved about us; there was no light save these purple and crimson beams. The man seemed adjusting his goggles, and replacing his headphone. Then he moved a switch. The crimson globe sprang into greater intensity. The beam from it deepened; it seemed streaming out across the room, through the further wall of metal rock--streaming out and opening to my gaze a blackness of distance unfathomable. A murmur was coming from it! A myriad tiny growls and screams! The crimson sounds! The red things lurking around me responded to it! Or were they making the sounds? I could not tell. They seemed rushing out from the unseen, into visibility--searching--one almost seemed plucking at me. * * * * *