Masonry
The walls of Cliff Palace present the finest masonry known to any cliff-dwelling and among the best stonework in prehistoric ruins north of Mexico. A majority of the stones used in the construction were well dressed before laying and smoothed after they were set in the wall. The joints are often broken, but it is rare to find intersecting walls or corners bonded. Stones of approximately the same size are employed, thereby making the courses, as a rule, level. Although commonly the foundations are composed of the largest stones, this is not an invariable rule, often larger stones being laid above smaller ones; the latter, even when used for foundations, are sometimes set on edge. As a rule, the walls are not plumb or straight. The custom of laying stone foundations on wooden beams is shown in several instances, especially in cases where it was necessary to bridge the intervals between projecting rocks. The arch was unknown to the masons of Cliff Palace; there are no pillars to support floors or roofs as in Spruce-tree House. It is not rare, especially in the kivas, to find instances of double or reenforced walls which may or may not be bonded by connecting stones.
The masonry of the kivas as a rule is superior to that of the secular rooms. The mortar employed in the construction is hard; the joints are chinked with spalls, fragments of pottery, or clay balls. The fact that much more mortar than was necessary was employed resulted in weakening the walls. Several walls were laid without mortar; in some of these the joints were pointed, in others not.[23] The ancient builders did not always seek solid bases for foundations, but built their walls in several instances on ashes or sand, evidently not knowing when the foundations were laid that other stories would later be constructed upon them.
In several sections of the ruin there are evidences that old walls, apparently of houses formerly used, served in part as walls for new buildings. There are also several instances of secondary construction in which old entrances are walled up or even buried and old passageways covered with new structures. Similar reconstruction is common in Hopi pueblos, where it has led to enlargement of rooms and other variations in form. Among the several examples of such secondary building in Cliff Palace may be mentioned a long wall, evidently the front of a large building, which serves as a rear wall of several rooms arranged side by side. The obvious explanation of such a condition is that the walls of the small rooms are of later construction.
As above mentioned the foundations of many walls are of larger stones, and the masonry here is coarser than higher up, which has led some authors to ascribe this fact as due to two epochs of construction. But this conclusion does not appear to be wholly justifiable, although there is evidence in many places that there has been rebuilding over old walls and consequent modification in new constructions, by which older walls have ceased to be necessary, a condition not unlike that existing in several of the Hopi pueblos. In this category may be included the several doors and windows that have been filled in with new masonry or even concealed by new walls. From the fragile character of certain foundations of high walls it would appear that it was not the intention, when they were laid, to erect on them walls more than one story high; the construction of higher stories upon them was an afterthought. Evidences occur of repair of breaks in the walls and corners by the aboriginal occupants, one of the most apparent of which appears at the end of the court in the southern wall of room 59.