t the rocks used
were similar in kind and shape to those composing the walls of all the
other kinds of construction in the _mesilla_ north of the church.

For what purpose these buildings were erected, and in what relation they
stood to _B_, I am unable to determine. Some of them appeared to have
doors opening to the east.[115] Beyond _f_ the ground rises suddenly.
The floor of those structures is, in some instances, formed of a black
or red loam. I excavated one of those, or, rather, dug into it, to the
depth of one metre. The surface had shown traces of a fire built in the
centre, and I found also, at the depth of nearly two feet, that the dark
soil was traversed by a band of charcoal, fragments of burnt and
blackened pottery, and some splinters of bone. Below it the soil was
dark red. Whether there was a buried hearth at that depth, or whether
the traces of fire were due to an original destruction of woodwork
through combustion, the _debris_ subsequently covering them with clay, I
am unable to judge.[116] In all of them, of course, pottery and obsidian
were found.

I have already stated that the _mesilla_ dips to the south-west; that
there is a depression along the northern end of its "neck;" and that
from _f_ the rocks bulge upwards again. All this contributes to
concentrate the drainage of the entire cliff-top, as far north of the
church as it was inhabited, in the hollow where the gate of the general
enclosure is placed. This gate was therefore not only a passage-way, but
also the water-gap or channel through which the _mesilla_ was finally
drained into the bottoms of the Arroyo de Pecos.

[Illustration: PLATE IV
PLAN OF BUILDING A.]

20 m.--65 ft.--to the N.N.W. of the mound i, there rises before us the
huge pile of ruins which, on the plat as well as on the diagram, I have
designated by _A_. It crowns the highest point of the entire _mesilla_,
and covers the greatest portion of its top. In ruins like _B_, its
general aspect is yet somewhat different Instead of forming, like the
latter, a narrow, solid rectangle of 140 m. x 20 m.--460 ft. x 65 ft.--,
the building _A_ is (taking, of course, the outlines of the entire
_debris_) a broad hollow rectangle of 150 m. x 75 m.--490 ft. x 245 ft.
Its interior is occupied by a vast court or square, containing three
circular depressions, and surrounded on all four sides by the broad
ruined heaps of the former dwellings. On the east side, between the
circumvallation and