ed that the ruin was not materially disfigured or
changed, and were they fully carried out the ruin would present much the
same general appearance as before. It is important that this appearance
should be preserved as far as possible, but it can not be maintained if
a roof is erected over the walls. As four years have elapsed since the
completion of the work, it should be possible now to determine whether
atmospheric erosion has played a material part in the work of
destruction.[1]

[Footnote 1: See the letter of the Director of the Bureau of
American Ethnology to the Secretary of the Interior regarding the
examination of Casa Grande by Mr W J McGee in the supplement to
the present paper.]

In the original plans and in the specifications which formed part of the
contract (although this section was not operative) a plan for a roof was
included. Such a structure, if erected at all, should be made as
inconspicuous as possible and should be supported entirely from within
the building. The system of framing employed might safely be left to the
contractor if he were made responsible for the strength of the completed
structure.

RESERVATION OF THE LAND

The final step in the execution of the law quoted was taken June 22,
1892. On that date the recommendation of the writer to the Director of
the Geological Survey, referred by him to the Secretary of the Interior
and by the latter to the President, was finally approved, and it was
ordered that an area of land sufficient for the preservation of the
ruin, and comprising in all 480 acres, be reserved under authority of
act of Congress approved March 2, 1889. This area is shown on the map
reproduced in plate CXXV, the base of which is a map accompanying the
report of Mr H. C. Rizer.

The letter of the Secretary of the Interior recommending the reservation
of the Casa Grande tract, with its indorsement by the President, is as
follows:

Department of the Interior,
_Washington, June 20, 1893_.

Sir: I have the honor to recommend that the SW. 1/4 SW. 1/4, SE. 1/4 SW.
1/4, SW. 1/4 SE. 1/4 section 9, NW. 1/4, NW. 1/4 NE. 1/4, SW. 1/4 NE. 1/4, NW. 1/4 SW.
1/4, NE. 1/4 SW. 1/4, and NW. 1/4 SE. 1/4 section 16, all in township 5 south,
range 8 east, Gila and Salt river meridian, Arizona, containing 480
acres more or less, and including the Casa Grande ruin, be reserved
in accordance with the authority vested in you by the act of March
2, 1889