Presently I heard the hum of a high-speed motor somewhere under the table. It throbbed softly through the auditory apparatus on the helmets. I shuddered at the terrific vibratory movements of the world I began to perceive. Suspended between two worlds, these new sounds grated like steel on my ears. I remembered that such vibrations were alien to the human organs and settled back to wait. I was startled by a sudden word from Dr. Korsakoff, for it pulled me back to our own world. "I didn't mean to frighten you, Arnoldi," he said, chuckling. "There's really nothing to be alarmed about. I merely wanted to tell you not to jump when I start the current flowing through the helmet. It will sound very weird on your ear-drums. Sit perfectly still and keep your eyes closed for best results. Open them very slowly, and a new world will be revealed. Now be perfectly still, my son. I am switching on the current. You keep your hands on the table. I will control the vibration from a panel at my side. Have an enjoyable visit into the Sixth Dimension--the Red World, Arnoldi!" I sat with closed eyes for a long time and felt drifting off. Then slowly I opened my eyes and was stunned by an amazing brilliancy of vari-hued lights. For a moment a pain shot through my eyes--they pained to the depths. Gradually it wore off. Crystals that ranged in color from deep, unfathomable red to emerald green danced before me. As though fighting for some control of a color-world the reds began to seep through into the blues and the greens. They suddenly merged into one solid color--the deep, unfathomable infra-red of the spectrum. The suddenness of the change caused my whole system to react in a terrific shudder. Remembering the scientist's words, I clenched my teeth for control over myself. Now I leaned forward tensely. Objects were slowly shaping themselves from the masses. It was the Red World! I thought I was gazing on a world of fire. Everything shimmered in what appeared to be a terrific heat. Then, as objects assumed definite form, I was able to detect the outlines of strange, luxurious vegetable growths. Weird trees and ferns stood on all sides. The sky overhead was of a red not less deep than the more concrete materials of Red Dimension. The earth--as it appeared, showed in open areas like blood-covered sandstone. Across it raced what appeared to be heat waves dancing on a hot, searing surface. Slowly the scene moved. Then I beheld a rather large clearing completely surrounded by the thick, tangled vegetation. I thought I caught a slight movement in a patch of swaying lush herbage. I watched the spot tensely. Slowly, very slowly, the blades parted and out of them protruded a weird snout. The thing was coming into view, slinking forward like a stalking panther.