80 CASA GRANDE, ARIZONA [erH, ANN. 28 
Grande Group, and the single structure, with standing walls, the Casa 
Grande ruin, or simply Casa Grande. 
Probably no two investigators would assign the same limits to the 
area covered by the group, as the margins of this area merge imper- 
ceptibly into the surrounding country. 
The bird’s-eye views here used (pls. 11, 12) to illustrate the relation 
of Casa Grande to the surrounding mounds are in general correct, 
although not entirely in agreement with the results of the excavations. 
According to Mindeleff, the area covered by the Casa Grande Group 
“extends about 1,800 feet north and south and 1,500 feet east and 
west, or a total area of about 65 acres.” ' 
The following description of Casa Grande is from Mindeleff :1 
The Casa Grande ruin is often referred to as an adobe structure. Adobe construc- 
tion, if we limit the word to its proper meaning, consists of the use of molded brick, 
dried in the sun but not baked. Adobe, as thus defined, is very largely used through- 
out the Southwest, more than 9 out of 10 houses erected by the Mexican population 
and many of those erected by the Pueblo Indians being so constructed; but, in the 
experience of the writer, it is never found in the older ruins, although seen to a limited 
extent in ruins known to belong to a period subsequent to the Spanish conquest. 
Its discovery, therefore, in the Casa Grande would be important; but no trace of it 
can be found. The walls are composed of huge blocks of earth, 3 to 5 feet long, 2 feet 
high, and 3 to 4 feet thick. These blocks were not molded and placed in situ, but 
were manufactured in place. The method adopted was probably the erection of a 
framework of canes or light poles, woven with reeds or grass, forming two parallel 
surfaces or planes, some 3 or 4 feet apart and about 5 feet long. Into this open box 
or trough was rammed clayey earth obtained from the immediate vicinity and mixed 
with water to a heavy paste. When the mass was sufliciently dry, the framework was 
moved along the wall and the operation repeated. This is the typical pisé or rammed- 
earth construction, and in the hands of skilled workmen it suffices for the construc- 
tion of quite elaborate buildings. As here used, however, the appliances were rude 
and the workmen unskilled. An inspection of the illustrations herewith, especially 
of Plate Ly [here pl. 10], showing the western wall of the ruin, will indicate clearly 
how this work was done. The horizontal lines, marking what may be called courses, 
are very well defined, and, while the vertical joints are not apparent in the illustration, 
a close inspection of the wallitself shows them. It will be noticed that the builders 
were unable to keep straight courses, and that occasional thin courses were put in to 
bring the wall up to a general level. This is even more noticeable in other parts of 
the ruin. It is probable that as the walls rose the exterior surface was smoothed with 
the hand or with some suitable implement, but it was not carefully finished like the 
interior, nor was it treated like the latter with a specially prepared material. . . . 
The floors of the rooms, which were also the roofs of the rooms below, were of the 
ordinary pueblo type, employed also to-day by the American and Mexican popula- 
tion of this region. . . . Over the primary series of joists was placed a layer of 
light poles, 14 to 2 inches in diameter, and over these reeds and coarse grass were 
spread. The prints of the light poles can still be seen on the walls. . . . 
The walls of the northern room are fairly well preserved, except in the north- 
eastern corner, which has fallen. The principal floor beams were of necessity laid 
north and south, across the shorter axis of the room, while the secondary series of poles, 
14 inches in diameter, have left their impression in the eastern and western walls. 
1In 13th Ann. Rep. Bur. Ethnol., p. 309 
