Now I could see the repellor rays that held the ship aloft, like searchlight beams faintly visible in the bright daylight (and still faintly visible to the human eye at night). Actually, I had been informed by my instructors, there were two rays; the visible one generated by the ship's apparatus, and directed toward the ground as a beam of "carrier" impulses; and the true repellor ray, the complement of the other in one sense, induced by the action of the "carrier" and reacting in a concentrating upward direction from the mass of the earth, becoming successively electronic, atomic and finally molecular, in its nature, according to various ratios of distance between earth mass and "carrier" source, until, in the last analysis, the ship itself actually is supported on an upward rushing column of air, much like a ball continuously supported on a fountain jet. The raider neared with incredible speed. Its rays were both slanted astern at a sharp angle, so that it slid forward with tremendous momentum. The ship was operating two disintegrator rays, though only in a casual, intermittent fashion. But whenever they flashed downward with blinding brilliancy, forest, rocks and ground melted instantaneously into nothing, where they played upon them. When later I inspected the scars left by these rays I found them some five feet deep and thirty feet wide, the exposed surfaces being lava-like in texture, but of a pale, iridescent, greenish hue. No systematic use of the rays was made by the ship, however, until it reached a point over the center of the valley--the center of the community's activities. There it came to a sudden stop by shooting its repellor beams sharply forward and easing them back gradually to the vertical, holding the ship floating and motionless. Then the work of destruction began systematically. Back and forth traveled the destroying rays, ploughing parallel furrows from hillside to hillside. We gasped in dismay, Wilma and I, as time after time we saw it plough through sections where we knew camps or plants were located. "This is awful," she moaned, a terrified question in her eyes. "How could they know the location so exactly, Tony? Did you see? They were never in doubt. They stalled at a predetermined spot--and--and it was exactly the right spot." We did not talk of what might happen if the rays were turned in our direction. We both knew. We would simply disintegrate in a split second into mere scattered electronic vibrations. Strangely enough, it was this self-reliant girl of the 25th Century, who clung to me, a relatively primitive man of the 20th, less familiar than she with the thought of this terrifying possibility, for moral support. We knew that many of our companions must have been whisked into absolute non-existence before our eyes in these few moments. The whole thing paralyzed us into mental and physical immobility for I do not know how long.