94 THE CLIFF RUINS OF CANYON DE CHELLY [ETH. ANN. 16 
years ago. When the movement to the summit of the mesa became 
general, the material of the old houses was utilized in the construction 
of the new ones, and at the present day it can almost be said that not 
one stone remains above another. So complete is the obliteration that 
no ground plan can be made out. 
If similar conditions prevailed in De Chelly, there might be many more 
ruins of this class than those so far discovered. Even those found are 
not easily distinguished and might easily be passed over. Possibly 
there were small ruins of this type scattered over the whole canyon 
bottom. An example which occurs at the point marked 12 on the map, 
and shown in plate XLIv, presents no trace on the surface except 
some potsherds, which in this locality mean nothing. The site is a low 
hill or end of a slope, the top of which is perhaps 25 feet above the 
stream bed, but separated from it by a belt of recent alluvium carpeted 
with grass. The hill itself was formed of talus, covered with alluvium, 
all but a small portion of which was subsequently cut away, leaving an 
almost vertical face 15 or 18 feet high. In this face the ends or vertical 
sections of several walls can be seen; one of themis nearly 3 feet thick 
and extends 4 feet below the present ground surface. 
The filling of these ruins to a depth of 4 or 5 feet and the almost 
complete absence of surface remains or indications does not necessarily 
imply a remote antiquity, although it suggests it. During the fall and 
early winter months tremendous sand storms rage in the canyon; the 
wind sweeps through the gorge with an almost irresistible power, carry- 
ing with it such immense quantities of sand that objects a few hundred 
feet distant can not be distinguished. These sand storms were and are 
potent factors in producing the picturesque features of the red cliffs 
forming the canyon walls; but they are constructive as well as destrue- 
tive, and cavities and hollow places in exposed situations such as the 
canyon bottom are soon filled up. The stream itself is also a powerful 
agent of destruction and construction; during flood periods banks of 
sand and alluvium are often cut away and sometimes others are formed. 
Yet there are reasons for believing that the old village ruins on open 
sites, now almost obliterated, mark the first period in the occupancy of 
the canyon, perhaps even a period distinctly separated from the others. 
Excavation on these sites would probably yield valuable results. 
II—HOME VILLAGES ON BOTTOM LANDS 
Ruins comprised in the second class are located on the bottom lands, 
generally at the base of a cliff, and without reference to the defensibil- 
ity of the site. They are, as a rule, much broken down, and might 
perhaps be classed with the ruins already described, but there are some 
distinctive features which justify usin separating them. Ruins of this 
class are always located either at the base of a cliff or in a cove under 
it, on the level or raised but slightly above the bottom land, and some- 
times at a considerable distance from the stream. The ground plans 
