The Repair of Casa Grande Ruin, Arizona, in 1891 | Page 4

more moist than the
remainder, although possibly only in an infinitesimal degree, is more
subject to erosion by flying sand in the windstorms so frequent in this
region, and gradually the base of the wall is eaten away until the
support becomes insufficient and the wall falls en masse. The plan
shows that in some places the walls have been eaten away at the ground
level to a depth of more than a foot. Portions of the south wall were in a
dangerous condition and likely to fall at any time.
Visiting tourists have done much damage by their vandalism. They
have torn out and carried away every lintel and every particle of visible
wood in the building. After the removal of the lintels a comparatively
short time elapses before the falling in of the wall above. Apparently
but a small amount of this damage can be attributed to rainstorms,
which, although rare in this region, are sometimes violent. There is
evidence that the present height of the walls is nearly the original
height, in other words, that the loss from surface erosion in several
centuries has been trifling, although numerous opinions to the contrary
have been expressed by causal observers. The eastern wall has suffered

more from this cause than the others; a belt on the northern half,
apparently softer than the remainder of the wall, has been eaten away to
a depth of nearly a foot. The interior wall faces are in good condition
generally, except about openings and in places near the top.
Evidences of the original flooring are preserved in several of the rooms,
especially in the north room. The flooring conformed to the pueblo type
in the use of a series of principal beams, about 3 inches in diameter,
above which was a secondary series smaller in size and placed quite
close together, and above this again a layer of rushes with a coating of
clay. All the walls show evidences of the principal series of beams in
the line of holes formed by their ends where they were embedded in the
walls. In the south wall, in parts of the east wall high up on the level of
the upper roof, and in parts of other walls a few stumps of floor beams
remained. These specimens of aboriginal woodwork have survived only
because they are not in sight from the ground, and their existence
therefore was not suspected by the tourists. Evidence of the other
features of the floor construction can be seen on the walls in places
where they have left an imprint, as described in the memoir previously
cited.
No single opening remains intact, as the lintels have been removed
from every one of them. This is particularly unfortunate, for openings
at their best are an element of weakness in a wall, and here each
opening, after the lintel was removed, became, as it were, a center of
weakness from which the destruction of the wall mass gradually
proceeded further and further.
PLANS FOR THE REPAIRS
The plans for the repair of the ruin and its preservation included the
reservation of the area covered by remains and, if possible, its inclosure,
for within that area are exhibited all the various degrees of decay and
disintegration which clearly link the comparatively well preserved Casa
Grande with the numerous almost obliterated ruins along the Gila and
the Salt, whose vestiges will become even less distinct as time passes
and cultivation increases.

It was deemed necessary to remove all the rubbish and debris within
the building and from an area measuring 10 feet from the outer walls in
every direction. Plate CXVII shows the extent of this area, and six
sections are shown in plates CXVIII and CXIX, three on east-and-west
lines and three on north-and-south lines. The lines along which these
sections were made are indicated on the plan, plate CXVII. The ground
level was determined by excavation, and is of course only approximate.
The sections show the estimated amount of debris which was to be
removed. Aside from other considerations, it was necessary to uncover
the walls to the ground level in order to do the necessary underpinning.
It was planned to underpin the walls, where erosion at the ground level
had weakened them, with hard-burned brick laid in cement mortar.
Plate CXVII shows in a measure the extent of this erosion. The brick
surface was to be set back an inch or two and faced with that thickness
of cement mortar. Plate CXX shows the south front and plate CXXI the
south and east fronts when the brickwork was completed, but before it
was plastered, and will illustrate what was planned better than can a
description.
This treatment, it was believed, would give a surface capable of
effectually resisting atmospheric influences and the destructive