sits. The mounds are composed
of gravelly cement and fine debris of house walls, and the rooms left
are completely filled with this material. It is easy to imagine how
the mounds were formed by the gradual demolition of the ceilings,
plastering, and roofs, forming a heap which to-day appears as shapely
as if it had been made by man for some definite purpose.

The houses were communal dwellings, each consisting of one room,
which generally was not quite ten feet square. The walls, eight
to nine inches thick, built of a mixture of clay and earth, were
fairly well preserved in places. In one house, which had unusually
solid compartments, the walls were twenty, and in some places even
thirty-three, inches thick. Here nothing could be found, either in
the rooms or by excavating below the floor. The same conventional
doorways were met with in all the mound houses, but there was hardly
any trace Of woodwork.

Excavations in one of the mounds near our camp disclosed very
interesting composite structures. One part of the walls consisted of
large posts set in the ground and plastered over, forming a stuccoed
palisade. At right angles with this was a wall of cobble-stones,
and among the buried debris were fragments of adobe bricks. In one
room of this group, at a depth of less than five feet, we struck a
floor of trodden concrete. Breaking through we found a huddle of six
or seven skeletons, which, however, were not entire.

Rarely if ever was any object found in these rooms, except, perhaps,
some stray axe, or some metates and grinding stones, and in one case
a square stone paint pot. But by digging below the concrete floors
we came upon skeletons which seemed to have been laid down without
regard to any rule, and with them were invariably buried some household
utensils, such as earthenware jars and bowls, beautifully decorated;
axes and mauls, fairly carved and polished. One very rare object was
secured: a doubled-grooved axe. The skeletons were badly preserved,
but we were able to gather several skulls and some of the larger bones.

The floor material was so hard that only by means of heavy iron
bars could we break through it. As it was impracticable for us to
make complete excavations, the number of rooms each mound contained
cannot be stated. There were in the immediate neighbourhood of Cave
Valley at least ten or twelve separate groups, each of which had
from four to eight rooms on the ground floor. The entire district i