I knew, of course, that red light penetrated clouds much better than other colors. I knew that the red light of a neon beacon is visible through miles of mist. I knew that the sun looks red on a murky day, because all but the red rays are absorbed by the atmosphere. I had an idea that a cloud had suddenly come between earth and sun, perhaps a haze of meteoric dust. But I failed to reassure myself. With a glance at the sun, which was gleaming at the zenith like a great red moon, I stepped upon the veranda, still feeling a slight weakness about the knees. Sam had risen to his feet. He stood gazing silently and blankly out to the eastern horizon, where the flaming intensity of the encrimsoned sky met the glancing brilliant beams from the darkened sea. There was no surprise in his expression, and little of fear--merely pain and despair. "What is it, Sam?" I asked quickly. He looked around slowly. "I don't know what it is, Mel, but it means the end of the earth! I've known for years that it was coming, but I hoped it wouldn't be so soon." "You knew that this was coming! And you didn't tell anybody! Not even me!" "It would have done no good. What would be the benefit to mankind to know that it was doomed to die like rats in a trap? A few more years, and I might have been ready to save the earth. As it is, there's just a chance--a bare chance!" "But what does it mean? It's uncanny!" He sat down again, wearily. There were lines of age and care on his lean face that I had never seen before. But even in the dull red light, there was still energy and determination in it. "I've never told you, Mel, but ever since the radio brought you your dream of the Green Girl, I have been working--building delicate apparatus and exploring the ether. And I found a strange force at work--a force that is battling to control the ether! For fifteen years I have known that it was working _to freeze the earth_!" "To freeze the earth!" "It seems so. What it is is a mystery, whose solution has resisted all my efforts. I can hardly conceive a reason for it. But I know that something is at work to cut us off from the sun! You know that light waves of different phases and the same frequency interfere, with mutual extinction--the diffraction grating is based on that fact. And interfering waves have been setting up such a disturbance in the ether about the earth as will ultimately cut off the sun's radiation! The principles of it are a bit abstruse. Even now, of course, the effect is only partially complete. In fact, the red and infra-red rays carry most of the sun's heat." "Then there's no immediate danger?" "No man knows at what moment the force may be synchronized. When it is, within a short time the temperature of the earth will fall to absolute zero. And even as it is, life could not go on long under this red pall, for all life depends upon the actinic rays in the ultra-violet spectrum." "And you have kept a thing like this to yourself for years!"