[Footnote 28: Isolated cliff-dwellings are scattered throughout the Southwest, but there are several areas, as the Mesa Verde, in which they are concentrated. Among these clusters may be mentioned the Canyon de Chelly, the Navaho National Monument, the Red Rocks area, and that of the upper Gila. One characteristic feature in which the cliff-dwellings of the Mesa Verde differ from some others is the independence of all of the upright walls from support of the sides of the cliffs. In the cliff-houses of the Navaho Monument a large majority of the houses have the rear wall of the cave as a wall of the building; a few of the houses in Cliff Palace have the same, but the largest number are entirely free from the cliff. This separation on all sides is due largely to the geological structure of the rear of the cavern in which the cliff-house stands.] There is also a vacant space between the rear of the Speaker-chief's House and the cave wall, but this space was almost entirely free of refuse. The amount of débris in the refuse heaps back of the so-called plaza quarter lends weight to other evidence that this is one of the oldest sections of Cliff Palace. The accumulation of débris was so deep in these places, and the difficulties of removal so great, that it was not attempted. It had all been dug over by relic seekers who are said to have found many specimens therein.[29] [Footnote 29: Workmen could operate in these parts only by tying sponges over their nostrils, so difficult was it to breathe on account of the fine dust.] SECULAR ROOMS The majority of the rooms in Cliff Palace were devoted to secular purposes. These are of several types, and differ in form, in position, and in function. Their form is either circular or rectangular, or some modification of these two. As a rule, the secular rooms lie deep under the cliffs, several extending as far back as the rear of the cave. The front of Cliff Palace shows at least two tiers or terraces of secular rooms, the roof of the lower one being level with that of the floor of the tier above. The front walls of secular rooms lower than the fourth terrace are as a rule destroyed, but the lateral walls are evident, especially in the tower quarter. The passage from one of these terraces to the room above was made by means of ladders or by stone steps along the corners. The following classification of secular rooms, based on their function, may be noted: (1) Living rooms; (2) milling rooms; (3) storage rooms; (4) rooms of unknown function;[30] (5) towers; (6) round rooms. It is difficult to distinguish in some instances to which of the above classes some of the rooms belong. The secular houses were probably owned by the oldest women of the clan, and the kivas were the property of the men of their respective clans, but courts, plazas, and passageways were common property. [Footnote 30: Possibly some of these may have been used sometimes for ceremonial purposes, or rather for the less important rites.]