I concluded this canyon hunting could bear some sustained attention and thought, as well as frenzied action.
Examination of my position showed how impossible it was to arrive at any clear idea of the depth or size, or condition of the canyon slopes from the main rim wall above.

The second wall--a stupendous, yellow-faced cliff two thousand feet high--curved to my left round to a point in front of me.

The intervening canyon might have been a half mile wide, and it might have been ten miles.

I had become disgusted with judging distance.

The slope above this second wall facing me ran up far above my head; it fairly towered, and this routed all my former judgments, because I remembered distinctly that from the rim this yellow and green mountain had appeared an insignificant little ridge.
But it was when I turned to gaze up behind me that I fully grasped the immensity of the place.