As we paced along, meditating, I became more sensibly impressed with the fact that our progress was down a rapid declination. The saline incrustations, fungi and stalagmites, rapidly changed in appearance, an endless variety of stony figures and vegetable cryptogams recurring successively before my eyes. They bore the shape of trees, shrubs, or animals, fixed and silent as statues: at least in my distorted condition of mind I could make out resemblances to many such familiar objects; the floor of the cavern became increasingly steeper, as was shown by the stalactites, which, hanging here and there from the invisible ceiling, made a decided angle with the floor, corresponding with a similar angle of the stalagmites below. Like an accompanying and encircling halo the ever present earth-light enveloped us, opening in front as we advanced, and vanishing in the rear. The sound of our footsteps gave back a peculiar, indescribable hollow echo, and our voices sounded ghost-like and unearthly, as if their origin was outside of our bodies, and at a distance. The peculiar resonance reminded me of noises reverberating in an empty cask or cistern. I was oppressed by an indescribable feeling of mystery and awe that grew deep and intense, until at last I could no longer bear the mental strain. "Hold, hold," I shouted, or tried to shout, and stopped suddenly, for although I had cried aloud, no sound escaped my lips. Then from a distance--could I believe my senses?--from a distance as an echo, the cry came back in the tones of my own voice, "Hold, hold." "Speak lower," said my guide, "speak very low, for now an effort such as you have made projects your voice far outside your body; the greater the exertion the farther away it appears." I grasped him by the arm and said slowly, determinedly, and in a suppressed tone: "I have come far enough into the secret caverns of the earth, without knowing our destination; acquaint me now with the object of this mysterious journey, I demand, and at once relieve this sense of uncertainty; otherwise I shall go no farther." [Illustration: "AN ENDLESS VARIETY OF STONY FIGURES."] "You are to proceed to the Sphere of Rest with me," he replied, "and in safety. Beyond that an Unknown Country lies, into which I have never ventured." "You speak in enigmas; what is this Sphere of Rest? Where is it?" "Your eyes have never seen anything similar; human philosophy has no conception of it, and I can not describe it," he said. "It is located in the body of the earth, and we will meet it about one thousand miles beyond the North Pole." "But I am in Kentucky," I replied; "do you think that I propose to walk to the North Pole, man--if man you be; that unreached goal is thousands of miles away."