On the 22d of October, 1867, we returned to Pichincha with another guide and entered the crater by a different route. Manuel, our Indian, led us to the south side, and over the brink we went. We were not long in realizing the danger of the undertaking. Here the snow concealed an ugly fissure or covered a treacherous rock (for nearly all the rocks are crumbling), there we must cross a mass of loose sand moving like a glacier down the almost vertical side of the crater; and on every hand rocks were giving way, and, gathering momentum at each revolution, went thundering down, leaping over precipices and jostling other rocks, which joined in the race, till they all struck the bottom with a deep rumbling sound, shivered like so many bomb-shells into a thousand pieces, and telling us what would be our fate if we made a single misstep. We followed our Indian in single file, keeping close together, that the stones set free by those in the rear might not dash those below from their feet; feeling our way with the greatest caution, clinging with our hands to the snow, sand, rocks, tufts of grass, or anything that would hold for a moment; now leaping over a chasm, now letting ourselves down from rock to rock; at times paralyzed with fear, and always with death staring us in the face; thus we scrambled for two hours and a half till we reached the bottom of the crater. Here we found a deeply furrowed plain strewn with ragged rocks, and containing a few patches of vegetation, with half a dozen species of flowers. In the centre is an irregular heap of stones, two hundred and sixty feet high by eight hundred in diameter. This is the cone of eruption,--its sides and summit covered with an imposing group of vents, seventy in number, all lined with sulphur and exhaling steam, black smoke, and sulphurous gas. The temperature of the vapor just within the fumarole is 184 deg., water boiling beside it at 189 deg.. The central vent or chimney gives forth a sound like the violent bubbling of boiling water. As we sat on this fiery mount surrounded by a circular rampart of rocks, and looked up at the immense towers of dark dolerite which ran up almost vertically to the height of twenty-five hundred feet above us, musing over the tremendous force which fashioned this awful amphitheatre,--spacious enough for all the gods of Tartarus to hold high carnival,--the clouds which hung in the thin air around the crest of the crater pealed forth thunder after thunder, which, reverberating from precipice to precipice, were answered by the crash of rocks let loose by the storm, till the whole mountain seemed to tremble like a leaf. Such acoustics, mingled with the flash of lightning and the smell of brimstone, made us believe that we had fairly got into the realm of Pluto. It is the spot where Dante's "Inferno" ought to be read. INCA HIGH-ROADS AND BRIDGES. E. GEORGE SQUIER.