■what extent wood and adobe were used can hardly be determined. It 

 is evident, however, that the greater portion of the vilhiges and dwell- 

 ings of the lowlands have been of material other than stone, frequently- 

 doubtless of rubble and adobe combined. 



As to situation, they may be classified very properly under three 

 heads: (1) lowland or agricultural settlements; (2) cave-dwellings; and 

 (3) cliff-houses or fortresses. 



Those of the first class are chiefly on the river-bottoms, in close prox- 

 imity to water, in the very midst of the most fertile lands, and located 

 without reference to security or means of defense. 



Those of the second are in the vicinity of agricultural lands, but built 

 in excavations in low-bluff faces of the Middle Cretaceous shales. The 

 sites are chosen also, I imagine, with reference to security ; while the situ- 

 ation of the cliff-houses is chosen totally with "reference to security and 

 defense, built high up in the steep and inaccessible cliffs, and having- 

 the least possible degree of convenience to field or water. 



As to use, the position for the most part determines that. The low- 

 land ruins are the remains of agricultural settlements, built and occu- 

 pied much as similar villages and dwellings would be occupied by peace- 

 able and unmolested peoples of to-day. The cave-dwellers, although 

 they may have been of the same tribe and contemporaneous, probably 

 built with reference to their peaceable occupations as well as to defense^ 

 and it is impossible to say whether or not they made these houses their 

 constant dwelling-places. The eliff'-houses could only have been used as 

 places of refuge and defense. During seasons of invasion and war, 

 families were probably sent to them for security, while the warriors 

 defended their property or went forth to battle; and one can readily 

 imagine that when the hour of total defeat came, they served as a last 

 resort for a desperate and disheartened people. 



In form, the parallelogram and circle predominate, and a consider- 

 able degree of architectural skill is displayed. Where the conforma- 

 tion of the ground i>ermits, the squares are perfect squares and the 

 circles perfect circles. A greater part of the ordinary structures are 

 square or rectangular; while attached to each group, and sometimes 

 without indications of contiguous buildings, are the circular ruins fre- 

 quently resembling towers. These are the most pretentious structures, 

 being often as much as forty feet in diameter, and in many cases having- 

 double or triple walls. They are solidly built of hewn stone, dressed on 

 the outside to the curve, neatly jointed, and laid in mortar. 



The space between the outer walls is invariably divided by heavy 

 partition- walls into a number of apartments, while a circular depression, 

 or estufa* occupies the center of the inclosure. 



It seems evident, from the extraordinary form of these structures 

 and the unusual care shown in their construction, that they were not 

 designed for the ordinary uses of dwelling or defense. It has beeja 

 observed that, among nearly all the ancient tribes of North America,. 

 the grandest and most elaborate works of art were the offspring of their 

 superstitions, and it does not seem at all improbable that these great 

 towers had a religious origin. 



It is stated that the eternal fire — an essential of their worship — bas 

 always been kept in circular inclosures, and that the circle symbojizes 

 the sun, their deity. The occurrence, therefore, of one or more of these- 

 circular inclosures in each of their settlements can be rationally 

 accounted for ; but it is with less certainty we arrive at conclusions in 

 regard to the triple walls and the cell-like apartments. In the inhabited 



*A Spanisli word signifying "sweat-house" or council-house. 



