Gradually, as we two stood in silence with our great craft speeding on, I became aware that during the last few minutes the air inside the pilot room had become perceptibly warmer, and that its warmth was still increasing. I glanced at the dial that registered the output of our heat-generators, but it was steady at its accustomed position; yet with each moment the warmth was increasing, until within a few minutes more the heat about us had become decidedly uncomfortable. Korus Kan, too, had noticed it, and had now swung backward the control of the heat-generators; yet still the warmth increased, the heated air in the pilot room rapidly becoming unbearable. I turned to the Antarian, fully alarmed now, but as I did so the door snapped open and Jhul Din burst up into the pilot room. "What's happening to the ship?" he cried. "Its inner walls are getting almost too hot to touch!" In stunned surprize we gazed at each other, our heating-mechanisms turned completely off now, yet the inside-temperature dial's arrow was still moving steadily forward! The thing was beyond all reason, we knew, and for an instant we stood in amazement, the heat increasing still about us. Then suddenly Jhul Din pointed upward toward the massed dials above the controls, his arm quivering. "Look!" he cried. "The outside-temperature dial!" Swiftly we raised our own eyes toward it, the dial upon which was shown the temperature outside the ship. It should have shown absolute zero, we knew, as always in the infinite cold of empty space. But now it did not, and our eyes widened as we stared at it, in utter astonishment and fear. _For it registered a temperature of thousands of degrees in the empty void about us!_ "Heat!" I cried. "Heat in empty outer space! It's unthinkable!" Unthinkable it was; yet, even as we stood and stared, the arrow on the outside-temperature was still creeping steadily forward, showing a swiftly increasing heat outside, while the air inside had become all but unbreathable, parching to the lungs. At the same moment a faint light began to appear about us, a dim-red glow that was intensifying with each moment that we raced onward, and as we wheeled toward the windows we saw, in the blackness of space before us, a great, faintly glowing region of red light ahead, stretching across the heaven before us. Ever stronger that crimson glow was growing as we raced on, the heat about us mounting with it, and from beneath came the cries of fear of our crew as they too glimpsed the awful region of heat and light through which we now were racing.