110 THE CLIFF RUINS OF CANYON DE CHELLY [ETH. ANN. 16 
ete. The buttress shown in the illustration is of stone and the front wall 
that it supports is slightly battened. A close inspection of the illus- 
tration will show that this wall rests partly on horizontal timber work, 
a feature which is repeated in several walls in the main cluster of the 
ruins. 
The use of timber laid horizontally under a wall is not uncommon, 
and as it will be discussed at greater length in another place, it may be 
dismissed here with the statement that as a rule it failed to accom- 
plish the purpose intended. But the use of the buttress is an anoma- 
lous feature which it is difficult to believe was of aboriginal conception. 
Its occurrence in this ruin together with so many other unaboriginal 
features is suggestive. 
The walls of the principal room and of the rooms immediately in 
front of it are constructed of stone; all the other walls in the upper 
ruin are of adobe or have adobe in them. The two rooms on the east 
and two walls of the room adjoining on the west are wholly of adobe, 
about 7 inches thick and now 3 and 4 feet high. In the southeast cor- 
ner of the second room from the east there is an opening through the 
front wall which may have been a drain. It is on the floor level, 
round, 5 inches in diameter, and smoothly plastered. In the fourth 
room from the east there is a similar hole. Both of these discharge on 
the edge of the cliff, and it is difficult to imagine their purpose unless 
they were expedients for draining the rooms; but this would imply 
that the rooms were not roofed. Although the cliff above is probably 
500 feet high, and overhangs to the degree that a rock pushed over its 
edge falls 15 feet or more outside of the outermost wall remains, and 
over 70 feet from the foot of the cliff, still a driving storm of rain or 
snow would leave considerable quantities of water in the front rooms 
if they were not roofed, and some means would have to be provided 
to carry it off. 
In the same room, the fourth from the east, there are the remains of 
a chimney-like strueture, the only one in the upper ruin. It is in the 
northeast corner, at a point where the wall has fallen and been replaced 
by a Navaho burial cist also fallen in ruin, and was constructed of stone. 
There is no doubt that it was added some time after the walls were 
built, as it has cracked off from the wall on the east, which shows at 
that point its original finish. In the eastern wall of this room there is 
a well-finished opening, and at the corresponding point in the wall of 
the room on the right, the third wall from the east, there is another. 
The latter wallis of adobe, or rather there are two adobe walls built side 
by side; one, the eastern, considerably thinner than the other. The 
opening extends through both walls; it was neatly finished and was 
closed by a thin slab of stone plastered in with mud. It has the appli- 
ance for closing mentioned above and described later (page 165). Most 
of the openings in the walls appear to have been closed up at the time 
the houses were abandoned. 
