MiNDELEFF] DESCRIPTION OF CASA GRANDE 323 



The exterior walls rise to a height of from 20 to 25 feet above the 

 grouud. This height accommodated two stories, but the top of the 

 wall is from 1 to 2 feet higher than the roof level of tlie second story. 

 The middle room or space was built up three stories higli, and the walls 

 are still standing to a Leight of 28 to 30 feet above the ground level. 

 The tops of the walls, while rough and greatly eroded, are approxi- 

 mately level. The exterior surface of the walls is rough, as shown in 

 the illustrations, but tlie interior walls of the rooms are finished with a 

 remarkable degree of smoothness, so nuich so that it has attracted the 

 attentiou of everyone who has visited the rum. Plate cxv shows tiiis 

 feature. At the ground level the exterior wall is from 3i to 4i feet 

 thick, and in one place over 5 feet thick. The mterior walls are from 

 3 to 4 feet thick. At the tops the wails are about 2 feet thick. The 

 building was constructed by crude methods, thoroughly aboriginal in 

 character, and there is no uniformity in its measurements. The walls, 

 eveu in the same room, are not of even thickness; the floor Joists were 

 seldom in a straight line, and measurements made at similar places 

 (for examj)le, at the two ends of a room) seldom agree. 



Casa Grande is often referred to as an adobe structure, but this use 

 of the term is misleading. Adobe construction consists of the use of 

 molded brick, dried in the sun, but not baked. The walls here are 

 composed of huge blocks of rammed earth, 3 to 5 feet long, 2 feet high 

 and 3 to 4 feet thick. These blocks were not molded and then laid in 

 the wall, but were manufactured in place. 



Plate cxvi shows the character of these blocks. The material 

 employed was admirably suited for the purpose, being when dry almost 

 as hard as sandstone and nearly as durable. A building with walls of 

 this material would last indeflnitely, provided a few slight repairs were 

 made at the conclusion of each rainy season. When abandoned, how- 

 ever, sapping at the ground level would commence and would in time 

 bring down all the walls; yet in the two centuries which have elapsed 

 since Padre Kino's visit to this place — and Casa Grande was then a 

 ruin — there has been but little destruction from the elements, the dam- 

 age done by relic hunters during the last twenty years being, in fact, 

 much greater than that due to all (-auses in the preceding two centuries. 



The building was well provided with doorways and other openings, 

 arranged in pairs, one above the other. There were doorways from 

 each room into every adjoining room, except that the rooms of the mid- 

 dle tier were entered only from the east. Some of the openings were 

 not used, and were closed with blocks of solid masonry, liuilt into them 

 long prior to the final abandonment of the structure. 



CONDITION OF CASA GRANDE IN 1891 



The south and east fronts of Casa Grande seem to have suffered 

 particularly from the weather, and here rainstorms have probably 

 caused some of the damage. The outer faces of the walls are of the 

 same material as the wall mass, all the masoury being composed of 



