24 INDIANS OF THE SOUTHWEST. 
BUILDINGS. 
The character of the buildings, ruins of which are 
found in the Southwest, depended in part upon the 
period in which they were built and in part upon the 
topography and other geographical conditions. 
In widely separated localities are ruins of small struc- 
tures mostly subterranean with walls of adobe supported 
by slabs of stones around the base on the outside. These 
houses were circular or oval, not rectangular, and appear 
to have had a conical roof of poles and thatch or earth. 
The character and style of the pottery indicate that 
these houses are older than the large community build- 
ings but that they belonged to the sedentary pueblo 
peoples rather than to the ancestors of the nomadic 
peoples now living in the Southwest. : 
There are also widely scattered ruins consisting of 
houses of a few rooms. Those in the Mesa Verde region 
have the rooms arranged on three sides of a small plaza 
in which is a circular room nearly or quite underground. 
There is an underground passageway from one of the 
rooms of the house leading to this circular chamber, 
which is-called by archaeologists a kiva. That the 
buildings belonged to a period older than that in which 
large community houses were built is indicated by the 
character of the pottery which is but crudely decorated. 
They may come next in order after the house in which 
slabs were used in connection with adobe walls. 
Sites. The building sites chosen by the prehistoric 
people seem to have depended in part upon the topog- 
raphy of the particular locality and in part upon the 
needs of defense in a given area. Few available caves 
seem to have been overlooked. The overhanging cliffs 
protected the building from rains and most such situa- 
tions were easily defended. The size of the buildings | 
is of course limited by the extent of the cave. Many 
