The southern portion of the building—the one which appears to have been erected on a plane surface—was, in all probability, the one first built. The northern portions were added to it gradually as occasion required. This is further shown by the fact that in these northern sections, along the line a, b, c, parts of the third story wall are patched with regular adobe bricks, about half as large as those in the church, but still made by the same process.[106] The rest of the structure is exclusively composed of stone.
It is to all intents and purposes a stone house. Two kinds of rocks predominate among the material; a slaty, gray and red, sandstone,—highly tabular, easily broken into plates of any size,—and a sandstone conglomerate, containing small pebbles from the size of a pea up to that of a small hazel-nut,—the whole rock of a gray color. When freshly broken or wetted, this conglomerate becomes very friable, and so soft that goats have left the impression of their feet on scattered fragments. When dry it becomes hard, and is always very heavy. Both kind of rocks are found in the vicinity of the mesilla. Besides[p. 56] these, loose pieces of stone from the bluff itself, boulders from the creek, of convenient size, enter into the composition of the walls. Sometimes the latter consist exclusively of slabs of sandstone superposed; again there are polygonal fragments of rocks piled upon one another, with courses of tabular sandstone, forming, so to say, the basis for further piling; the foundations are usually boulders and the hardest rocks, also of greater width. There are no walls of dressed stone, but the rocks are broken to a suitable size, as may be done with any stone maul or sledge, or even by smashing with the hand and another rock. In fact the whole stone-work must be termed, not masonry, but simply judicious and careful piling.[107] In performing it, great attention has been paid to having the vertical surfaces as nearly as possible vertical; but this end could be reached without the use of the plumb-line, and with the aid of mere ordinary eyesight, for the rooms are so small, and the partitions so thin, that anything not "true" could, and can yet be, "shoved" into position by a mere steady, slow push; carefully watched on the opposite side. The same applies to the angles, although they are tolerably accurate. As a general thing, the transverse walls appear to be continuous, and the longitudinal partitions to have been added afterwards, but there are also instances of the contrary. In this respect the sinuosities of the rocky foundation seem to have determined the mode of action. To fill up the gaps between the stones,[p. 57] and to coat them with a smooth surface within the chambers what appears to be earth from the surrounding bottoms has been flung into the crevices, thus forming a natural mortar, and at the same time a "first coat" of plaster of varying thickness. This in turn is covered with a thin white layer (now of course turning into gray, yellow, and flesh-red) much resembling our plaster, but whose composition I am unable to determine. (Specimens of the mud, containing small gravel and minute particles of mica, are sent with the other collections, also fragments of the white coating for analysis.[108])
The woodwork proper appears not to have had any connection with the strength or support of the walls, but simply to have been erected within and among the walls as a scaffold for the ceilings, which are also the floors of the higher stories. Upright posts of cedar and pine, stripped of their bark, but not squared, are, as I have already shown, set inside of the stone wall, at more or less even distances. As far as I[p. 58] could ascertain, these distances are regulated by the size of the rooms. These posts are coarsely hacked off at the upper end, and over them other similar beams are laid longitudinally, sometimes fitted over the posts with chips wedged in. Such is the case in a room in the northern wing of the building marked A, of which I shall hereafter speak.[109]
On these longitudinal beams other ones rest, laid transversely, and imbedded in the wall on the opposite side. On these again longitudinal poles are placed, also at intervals varying according to the dimensions of the chambers, and on them transversely, a layer of brush, or splinters of wood, closely overlapping each other; and the whole is capped by about .20 m.—8 in.—of common clay or soil. [Pl. III.], Fig. 1, is a front view of the wooden scaffold in a lower story room, and of the ceiling which it supports.
a, clay and lower seam of brush or splinters.
b, transverse poles or beams, in case the beams are lacking.
c, longitudinal beam.
d, upright posts.
In most cases, however, the beams are transverse and the poles longitudinal, and this is where the beam (c) is lacking, as in the interior apartments, where the ceiling appears as in [Pl. III.], Fig. 2: a, clay; b, brush or splinters; c, poles; d, beams; e, wall.[110]
The diameter of the upright posts is, on an average, 0.28 m.—11 in.,—but even sometimes as great as 0.33 m.—13 in.,—the longitudinal and transverse beams are scarcely less thick, whereas the poles are about 0.05 m.—2 in.—across. The splinters seem to have been obtained by splitting a middle-sized tree, and tearing out thin segments.