The rear walls of rooms 89 and 90 are well preserved, but those in front have been completely destroyed. The former has a banquette like that of the Speaker-chief's House. The walls of rooms situated north and east of kiva U, now reduced in height, formerly extended to the roof of the cave, which is here somewhat lower than in the middle of the cavern. The existence of these former walls is indicated by light bands on the smoke-covered surface of the cave roof, and fragments of clay still adhering to the side of the cliff show that the walls here were two and three stories high. In rooms 84, 85, and 86 the builder took advantage of the cliff for rear walls. The middle of the floor of 84 has a depression lined with vertical slabs of stone, evidently a fireplace, as it contained a quantity of wood ashes. In the floor on the eastern side of this fireplace there is a short trench also lined with stone and containing wood ashes, the relation of which to the other inclosure is unknown. It appears that this exceptional structure was not used in the same way as the fireplaces so constantly met with in other rooms, but that it might have been used for baking paper-bread, called _piki_ by the Hopi. In a corner of room 91 there is another depression, half under the floor, covered with a flat stone, that appears quite likely to have been used for this purpose. Unlike the fireplaces sunken in the floor, the one in room 84 is partially or wholly above the floor, its confining stones being several inches above the floor level. Room 92 is the best example of a milling room in Cliff Palace. It has four grinding bins, or metatakis, arranged side by side, with all the parts entire and in working condition. When excavation was begun in this part of the ruin these structures were wholly concealed under fallen rocks. As streams of water from a vertical cleft in the cliff poured down upon them after exposure during periods of rain, it was necessary to construct a roof to protect them.[42] The discovery of this and of other grinding rooms shows that the cliff-house metatakis are the same in structure as those in the Hopi pueblos. In an inclosure south of these metatakis was found a granary. Fragments of walls projecting from the cliff west of room 93 show the former existence of rooms in this section, but as their front walls have been obliterated by the downpour of water their form is obscure. [Footnote 42: On the top of the rock that forms the foundation of the walls of these rooms, and south of them, are hollows or grooves where the metates were ground, and shallow pits used in some prehistoric game. There are similar pits in some of the kiva floors.] KIVAS