FEWKES] EXCAVATIONS AT CASA GRANDE, ARIZONA 295 



eight feet from the main building. It extended southward, forming 

 the main wall of the central building and the east wall of the south- 

 west plaza. This extension of the ceremonial rooms may once have 

 been the east wall of a narrow compound containing the main build- 

 ing and the cluster at the northwest angle of the original compound. 

 On this hypothesis the rooms east of Casa Grande may have been ad- 

 ditions, the buildings of the northeast, central, and east plazas not 

 having been included formerly within the walls that surrounded the 

 main building. 



It appears from the author's explorations that the main building 

 does not stand in the middle of Compound A, but is nearer the west 

 and south sides than the east and north. The most important build- 

 ings of the present enclosure are situated on the east, north, and 

 south sides of Casa Grande, those on the west being small and in- 

 conspicuous. This arrangement was evidently intentional, primarily 

 heliotropic, that is, for the purpose of allowing outlooks from roofs 

 to the east for sun worship or other ceremonial purposes. 1 



The main building was not isolated from the others, but connected 

 with them at its base on the east, north, and south sides. The roofs 

 of neighboring buildings communicated directly with a terrace on a 

 level with the lower rooms of the main building, which opened upon 

 the terrace through low, narrow entrances. By the use of ladders 

 one could mount to the doorways of the second story of the main 

 building, which were situated on the east, north, and south sides. 



The south wall of Compound A is curved slightly outward, the 

 curvature reaching its maximum at the point of union of the north 

 wall of the six ceremonial rooms, where it is over two feet, or a little 

 more than the width of the wall. The west wall is without curve 

 from the northwest to the southwest corner, and is a fine specimen 

 of aboriginal masonry constructed without instruments of precision. 

 The south wall, which is a little more than half the length of the 

 west wall, is likewise straight. This is also true of the east wall, 

 which, however, is double at the northeast end, being broken by a 

 small jog or reentrant angle about a hundred feet from the northeast 

 corner of the compound. 2 



The purpose of the double wall at the northeast angle of the com- 

 pound is not known ; perhaps it is connected in some way with the 



1 The openings in Casa Grande through which the sun priest watched the 

 rising and setting sun are still visible. Their use, as mentioned by early 

 writers, will be discussed in a final report on the building and its purposes. 



2 A similar break in the wall is also found in the Casa Blanca compound. 



