The interior of the room, like the circular kivas already described, appears to have been plastered with a number of successive coats, all except the last being heavily stained by smoke. If the structure were a chimney, it was a dismal failure. The tunnel was made at the time the wall was erected, and passes under the bowlder over which the wall was built. A little east of the opening, inside the room, the bowlder shows through the wall, projecting slightly beyond its face. [Illustration: Fig. 79--Section of chimney-like structure in ruin 15.] Outside of the room the corner of the bowlder was chipped off, as shown on the plan, to permit the rounding of the shaft, the east, west, and south sides of which were built up with small pieces of stone, a kind of lining of masonry. There was also an outside structure of masonry, but how high above the ground it extended can not now be determined. A small fragment of this masonry is still left on the upper surface of the bowlder and is shown in the section. Figure 80 is a plan of another example, which is attached to the circular kiva in ruin No. 16. This ruin is described on page 129. The kiva had an interior bench and the floor is 2 feet above its top. On the south side nearest the cliff edge the bench is interrupted to give place to a structure much like that described above. In this case, however, there was no convenient bowlder, and the roof of the tunnel has broken down so that the method of support can not be accurately determined. Probably it consisted of slabs of rock, as the span is small, and a number of large flat stones were removed from the tunnel in excavating. The top of the tunnel is on the level of the top of the bench, as shown in figure 81, which is a vertical section. An inspection of the plan will show that the circular wall of the kiva is complete and that the inclosing rectangular wall was added later. The shaft was built at a still later period, and the line or junction marking its inner surface shows plainly in the interior of the tunnel. The general view of the ruin (plate LI) shows the exterior of the shaft, and the horizontal timbers on which the masonry is supported are shown in plate LII. In front of the tunnel a flat piece of stone was placed on the floor, and in front of this again, about 2 feet from the mouth of the tunnel, there was an upright mass of masonry composed of stone and mud, and forming a curtain or screen before the opening. The original height of this structure was the same as that of the interior bench.