The cutting of this path in itself was a tedious task, and gave some idea of the labour that would have been involved in tunnelling the rock. This narrow shelf, however, proved of inestimable value in handling the heavy overhead members of metal and setting them into position. The dimensions and weight of the latter had to be kept as low as possible to facilitate handling under the peculiarly cramped conditions. Actual erection was exciting and hazardous. The men had to be lowered by ropes and had to ply their tools while swinging in mid-air or when clinging to precarious footholds. However, the cumbrous overhead pieces were successfully set in position, the ends were bolted to brackets sunk deeply into the cliff faces, and from these girders the track floor was suspended, the ends resting on the solid edges of the rocky ledge, while one side was bedded against the wall. Such is the story, as communicated to me by the engineers, of the origin and erection of what ranks as an unparalleled novelty in engineering. The “Hanging Bridge” was built in the Royal Gorge nearly 30 years ago, and although the first structure has been replaced by one of larger and heavier dimensions to accommodate weightier trains, the fundamental principle is precisely the same as conceived by Mr. Robinson. Yet the “Hanging Bridge” is but one of many engineering wonders to be found on this railway. Go where one will over its 1,800 miles of track among the Rockies, and some striking and daring work confronts one at every turn. Here the railway threads its way through a winding abyss, there it passes over the crown of a towering peak, or toils laboriously up the side of a sheering cliff. No two miles are alike. In all it traverses five yawning canyons, each possessing a strange individuality, and crosses the mountain backbone by which the continent is split in twain by three different passes. Level sections are practically unknown. It is one continuous up-hill pull up the one, with a long coast down-hill with steam shut off, on the other, side--a switchback upon a stupendous scale. Let us take the route over the Marshall Pass. At Poncha, on the Atlantic side, the line is at an altitude of 7,480 feet. The summit is six miles away by the iron road, but in that distance the train has to climb steadily at 211 feet to the mile over an extremely meandering route. The mountains become wilder and more broken as the summit is approached. The engineer took advantage of every natural facility that opened up to him. In turn the rail crawls along ledges cut in the mountain flanks, over lofty embankments, spidery trestles, doubling and redoubling upon itself in the most amazing manner. The occasional presence of snow-sheds draws attention to the fact that the metals are above the snow-line, and the many terrible dangers to which the track is exposed from avalanches and landslides.