Notwithstanding the sterile nature of the country, the trappers, during their passage up the Gila, saw with astonishment that the arid and barren valley had once been peopled by a race of men far superior to the present nomade tribes who roam over it. With no little awe they gazed upon the ruined walls of large cities, and the remains of houses, with their ponderous beams and joists, still testifying to the skill and industry with which they were constructed: huge ditches and irrigating canals, now filled with rank vegetation, furrowed the plains in the vicinity, marking the spot where once the green waving maize and smiling gardens covered what now was a bare and sandy desert. Pieces of broken pottery, of domestic utensils, stained with bright colours, every where strewed the ground; and spear and arrow-heads of stone, and quaintly carved idols, and women's ornaments of agate and obsidian, were picked up often by the wondering trappers, examined with child-like curiosity, and thrown carelessly aside.[4] [4] The Aztecs are supposed to have built this city during their migration to the south; there is little doubt, however, but that the region extending from the Gila to the Great Salt Lake, and embracing the province of New Mexico, was the locality from which they emigrated. A Taos Indian, who was amongst the band, was evidently impressed with a melancholy awe, as he regarded these ancient monuments of his fallen people. At midnight he rose from his blanket and left the camp, which was in the vicinity of the ruined city, stealthily picking his way through the line of slumbering forms which lay around; and the watchful sentinel observed him approach the ruins with a slow and reverential gait. Entering the mouldering walls, he gazed silently around, where in ages past his ancestors trod proudly, a civilised race, the tradition of which, well known to his people, served but to make their present degraded position more galling and apparent. Cowering under the shadow of a crumbling wall, the Indian drew his blanket over his head, and conjured to his mind's eye the former power and grandeur of his race,--that warlike people who, forsaking their own country for causes of which not the most dim tradition affords a trace, sought in the fruitful and teeming valleys of the south for a soil and climate which their own lands did not afford; and displacing the wild and barbarous hordes which inhabited the land, raised there a mighty empire, great in riches and civilisation, of which but the vague tradition now remains.