40 TWO summers' M^ORK TN pueblo ruins [eth. ANN. 22 



The black lava covers the red sandstone, forming great mesas or 

 isolated bnttes, the summits of which are crowned with ruins. The 

 lava ruins have low, rough walls, iu which adobe mortar was not 

 detected. The red sandstone formed a more tractable material, and 

 the buildings constructed of it show tine masonry with adobe mortar. 

 These ruins ordinarily stand on the brinks of small canyons eroded in 

 the sandstone, on isolated blocks of the same stone, or on ridges left 

 by erosion. If these lava and red sandstone ruins were found in dif- 

 ferent localities they might be regarded as products of different peo- 

 ples, but their existence side by side in this region shows that the 

 slight differences in their architecture were due simply to the build- 

 ing materials employed. The irregular forms of the lava lilocks made 

 it impossible to construct from them the fine i-ectilinear walls which 

 were jjossible with the well-squared blocks of sandstone. The erosion 

 of the lava produces a coal-black, porous sand, which as a rule covers 

 the finer red soil derived from the sandstone. This soil, drifting into 

 pockets or depressions in the surface rocks, afforded burial places for 

 the inhabitants of the villages. 



This region has few trees; there are no pines, and only a few cedars. 

 It is the same sagebrush counti-y which we find near the upper Little 

 Colorado at Ilolbrook and Winslow. 



The region is arid; it now has few springs, those which were 

 used in ancient times having probably been filled by drifting sand.'' 

 Volcanic agencies have left their mark on the whole region, causing 

 in places deep fissures in the rocks, into some of which a strong cur- 

 vent of air continually passes, and from one of which emerges a roar 

 as though of suljterranean currents of water. One of the largest of 

 these fissures is about 2 miles from the Tuba road, on the waj' to 

 the ruifis called group A; others are found in the rocks near ruins 

 G and H of this cluster, where their depth has not been determined. 

 These crevasses, which are no unusual feature in the geology of this 

 region, vary in breadth from a few inches to many hundred feet, and 

 from a hundred jards to miles in length. When ^ery broad they 

 form canyons which end abruptly or merge into "washes" as the con- 

 figuration of the country maj" dictate. 



General Features 



The ruins near Black falls are as a rule rectangular in form, with 

 similarly shaped rooms of one or more stories. Curved walls are 

 rare, although in some instances the shape of the ruin follows the 

 curvature of the mesa on which it stands. As has been stated, the 

 ruins are bviilt of both sandstone and lava, and the two varieties are 

 found in close j)roximity, sometimes within a few hundred feet of 



^ The author does not share a common belief that when these now i-uinod structures were 

 inhabited the precipitation was greater. In an arid region springs are rapidly filled by drifting 

 sand if not dug out repeatedly. The Hopis are obliged to clean out some of their largest springs 

 annually. 



