Just as we of earth, in a wide variety of forms, had learned to harness electricity, so on Xenephrene, Reet was harnessed. On earth a common electrical current, a bolt of lightning, a magnetic field, fluorescence of a Crooke's tube, the heat of an electric coil, a giant, leaping electric spark, the X-ray, radio waves--all are akin. We know that now; we learn it more surely every year. On Xenephrene, a score of scientific phenomena were all manifestations of Reet, in various forms, under various abnormal conditions. * * * * * Our earth now is using Reet for the anti-gravity vehicles which now are adventuring into Space; and our scientists say that Reet itself is but another form of electrical force. Father told us how our vehicle operated. The force of gravity itself is merely a vibration flowing between two material bodies, connecting them with a tendency to draw near, to coalesce--a fundamental tendency in all nature when in vibratory contact. The Reet current, applied in a form abnormal to nature, slows down and stops this gravitational vibration. It is, to me at least, a deep subject; I leave it to father's text books. But with several of the Reet rays, we were to have diabolical dealings! Their control of the hidden, unseen forces of nature--we saw a little of it that afternoon in the Scientists' Grotto. The grotto, at least this one to which we were admitted, seemed to be a series of underground passages; converging into a number of underground rooms. Workshops; laboratories; storehouses, perhaps, of weapons and equipment of war. We were shown none of that; we saw, indeed, but one room. Enough to leave us shuddering. On the ground, beneath the forest, we came to the tunnel entrance. A guard--a man standing there, with half a dozen of the insect things lying watchfully beside him, passed us in. A tunnel sloping downward; smooth, gleaming, metallic walls; shifting purple and red lights; a steady movement of artificially controlled air for ventilation; vague, pungent smells; in the distance, ahead of us, the murmur and throb of machinery. It was like plunging into yet another brand new world. Outside the grotto, the Garlands seemed a primitive, pastoral race. This was like a plunge, centuries into the future. An inferno of the future. From a cross tunnel, the sudden whine of a dynamo tore at us. A wave of gas, not unlike chlorine, Freddie said, brought us up gasping and choking, until a blast of fresh cool air fortunately dissipated it. A place of shifting lurid lights; workmen passed us--sometimes with masks, but all wearing what seemed heavy insulated garments. An inferno, frightening in its strangeness. Frightening, also, in another way. The half-seen world of the Infra-red had never left my consciousness since I first set foot upon Xenephrene. It was with me all that morning in the upper streets of Garla, but I had ignored it.