About half-past five I found myself a few hundred feet below timber-line in the lone valley, which was already beginning to look shadowy and a little uncanny, the tall ridges that leaped up at the right obscuring the light of the declining sun. My purpose had been to find accommodations at a mountaineer's cabin far down the valley, in the neighborhood of the Seven Lakes; but I had tarried too long on the mountain, absorbed in watching the birds, and the danger now was that, if I ventured farther down the hollow, I should lose my way and be compelled to spend the night alone in this deserted place. I am neither very brave nor very cowardly; but, in any case, such a prospect was not pleasing to contemplate. Besides, I was by no means sure of being able to secure lodgings at the mountaineer's shanty, even if I should be able to find it in the dark. There seemed to be only one thing to do--to climb back to the signal station on the summit. I turned about and began the ascent. How much steeper the acclivities were than they had seemed to be when I came down! My limbs ached before I had gone many rods, and my breath came short. Upward I toiled, and by the time my trail reached the cog-road I was ready to drop from exhaustion. Yet I had not gone more than a third of the way to the top. I had had no supper, but was too weary even to crave food, my only desire being to find some place wherein to rest. Night had now come, but fortunately the moon shone brightly from a sky that was almost clear, and I had no difficulty in following the road. Wearily I began to climb up the steep cog-wheel track. Having trudged around one curve, I came to a portion of the road that stretched straight up before me for what seemed an almost interminable distance, and, oh! the way looked so steep, almost as if it would tumble back upon my head. Could I ever drag myself up to the next bend in the track? By a prodigious effort I did this at last--it seemed "at last" to me, at all events--and, lo! there gleamed before me another long stretch of four steel rails. My breath came shorter and shorter, until I was compelled to open my mouth widely and gasp the cold, rarefied air, which, it seemed, would not fill my chest with the needed oxygen. Sharp pains shot through my lungs, especially in the extremities far down in the chest; my head and eye-balls ached, and it seemed sometimes as if they would burst; my limbs trembled with weakness, and I tottered and reeled like a drunken man from side to side of the road, having to watch carefully lest I might topple over the edge and meet with a serious accident. Still that relentless track, with its quartette of steel rails, stretched steep before me in the distance.