I pondered, revolving in my mind the fact that persons had in mental abstraction, passed through unusual experiences in ignorance of conditions about them, until their attention had been called to the seen and yet unnoticed surroundings, and they had then beheld the facts plainly. The puzzle picture (see p. 129) stares the eye and impresses the retina, but is devoid of character until the hidden form is developed in the mind, and then that form is always prominent to the eye. My remarkably light step, now that my attention had been directed thereto, was constantly in my mind, and I found myself suddenly possessed of the strength of a man, but with the weight of an infant. I raised my feet without an effort; they seemed destitute of weight; I leaped about, tumbled, and rolled over and over on the smooth stone floor without injury. It appeared that I had become the airy similitude of my former self, my material substance having wasted away without a corresponding impairment of strength.I pinched my flesh to be assured that all was not a dream, and then endeavored to convince myself that I was the victim of delirium; but in vain. Too sternly my self-existence confronted me as a reality, a cruel reality. A species of intoxication possessed me once more, and I now hoped for the end, whatever it might be. We resumed our journey, and rushed on with increasing rapidity, galloping hand in hand, down, down, ever downward into the illuminated crevice of the earth. The spectral light by which we were aureoled increased in intensity, as by arithmetical progression, and I could now distinguish objects at a considerable distance before us. My spirits rose as if I were under the influence of a potent stimulant; a liveliness that was the opposite of my recent despondency had gained control, and I was again possessed of a delicious mental sensation, to which I can only refer as a most rapturous exhilaration. My guide grasped my hand firmly, and his touch, instead of revolting me as formerly it had done, gave pleasure. We together leaped over great inequalities in the floor, performing these aerial feats almost as easily as a bird flies. Indeed, I felt that I possessed the power of flight, for we bounded fearlessly down great declivities and over abysses that were often perpendicular, and many times our height. A very slight muscular exertion was sufficient to carry us rods of distance, and almost tiptoeing we skimmed with ever-increasing speed down the steeps of that unknown declivity. At length my guide held back; we gradually lessened our velocity, and, after a time, rested beside a horizontal substance that lay before us, apparently a sheet of glass, rigid, immovable, immeasurably great, that stretched as a level surface before us, vividly distinct in the brightness of an earth light, that now proved to be superior to sunshine. Far as the eye could reach, the glassy barrier to our further progress spread as a crystal mirror in