The sky was utterly black, above that desolate purple world. The stars were blazing with strange splendor, like a mist of sunlit diamond dust. They were brighter than they ever are on earth, for we were above the atmosphere. I turned toward the east, to look at the morning sun. Its light was blinding. The solar corona spread out like great wings from a sphere of livid white. And on the purple desert, below the blazing sun, was a city! Great spires and towers and domes rose above the dull flat expanse of purple and blue and violet. The strange buildings were scarlet. They gleamed with a metallic luster, as if they were made of the same metal as the red airplanes. This was the land of the madman's allies, the home of the purple, gleaming creatures! In all that strange world, save for the intense red of the weird city, there was no bright color. The smooth plains, the towering mountains, the great lakes, were dull purple or blue or violet. And all were semi-transparent! I could see the Sierra Madre like a little gray ridge, scores of miles below. And in the west, below those purple mountains, was the broad blue Pacific, gleaming like steel. I cried out in wonder to the guard. "Huh," he muttered. "It's nothin'. I've been up here a dozen times. Nothin' solid. Just mist. Even the--Things--cut like butter." The Second Shell Certainly our machine had risen easily enough through the purple rocks below us. The scientific aspects of that second crust about the earth have been considered very carefully, and the best scientific opinions have been sought. Mankind dwells upon a comparatively thin crust about the molten or plastic interior of the earth. It would seem there is a similar crust about the air. Science long ago had evidence of it in the reflection of radio waves by the so-called Heaviside Layer. The volume of the gases in the atmosphere depends upon temperature and pressure. As one leaves the surface of the earth, the air grows thinner, because the pressure is less. But interplanetary space is nearly at absolute zero, where molecular motion ceases. It follows that the molecular motion of the outside of the atmosphere is not sufficient to keep it in the gaseous state at all. The top of the air is literally frozen into a solid layer!