"I've never heard of anyone ever doing it except in this book, sir," I protested. "And the experiences set down here sound more like fiction than actual fact. Who was this Dr. Valenev, anyhow?" "Valenev?" Dr. Korsakoff said, brows arching. "Have I neglected to recount his life to you?" "Rather I have neglected reading his works, sir," I replied. "Vladimir Valenev, Arnoldi, was one of the very first Russians to take up the practice and study of optometry in the early days. He was actually the father of the profession in Russia. But his startling discoveries branded him as a fool and he was discredited by the church and state. He was eventually strung up by the thumbs in old St. Petersburg for an exhibition to black magic. "Most of his statements were without concrete foundation, and they led him presently to his death. Yet for all that, Arnoldi, have you ever thought it might be possible to create a pair of spectacles through which one could see into the beyond?" I stiffened in the chair and the heavy book thumped on the floor. I surveyed his serious features for a sign that he was jesting. "I've never thought of such a thing, sir," I said, shaking my head. "In fact I do think it is quite impossible with any glass or series of glasses which we have today." "Naturally, Arnoldi," he said, "it could not be done with our present chromatic glasses. Yet it _is_ possible to penetrate the beyond--the planes of existence beyond our own." "What do you mean, sir?" I asked. "You already know that we exist in a world that wise scientists realize is very limited. Atomic vibration, my dear Arnoldi, has created a varied series of planes of existence, to which the human retina and the human auditory organs are totally out of accord. That is--everything vibrating within the perceptions of our own immediate powers of sense manifests itself in the form of concrete material matter, such as myself and yourself and objects in this room, perceptible by sound, sight, smell, touch, and so forth. Everything below or extremely above our accustomed vibratory limits is to us non existent. You are aware that there are sounds so high in pitch or frequency that the human auditory system cannot hear them. Also there are objects that emit vibrations whose low frequency makes them invisible to the eye." "You have taught me to understand that, sir," I replied, beginning to have a dim, awed feeling of what was to come. Surely he had not evolved a pair of glasses adjusting our senses to vibration frequencies beyond our natural limit, for he would have told me of it. But I had learned to know two sides of Dr. Korsakoff. Although he took great pride in explaining his experiments to me, he secretly guarded his plans and formulae until he could offer concrete proof of their feasibility.