eady mentioned, was not part of it. The northern wall of this room
seems to have run through to the outside, on the east, as though at one
time it formed the exterior wall of the structure; and the eastern wall
of the building north of this room is separated from the rest of the
wall by a wide crack, as though it had been built against a smooth
surface. The western wall of this room shows clearly that in the
construction of the building the floor beams were laid on the tops of
the walls, and that the intervening spaces were filled with small lumps
of material up to a level with or a little above the upper surface of
the beams, the regular construction with large blocks being then
resumed.

In the middle room many blocks bearing the imprint of grass and rushes
were found, and the rough marking of the walls just above the floor
beams is covered in places in this room with masonry composed of these
grass marked blocks projecting some distance into the room, indicating
that in this room at least they mark the position of a bench. These
blocks occupy the whole thickness of the setback at the second roof
level--perhaps an indication that the upper story was added after the
building was occupied.

_Openings._

The Casa Grande was well provided with doorways and other openings
arranged in pairs one above the other. There were doorways from each
room into each adjoining room, except that the middle room was entered
only from the east. Some of the openings were not used and were closed
with blocks of solid masonry built into them long prior to the final
abandonment of the ruin.

The middle room had three doorways, one above the other, all opening
eastward. The lowest doorway opened directly on the floor level, and was
2 feet wide, with vertical sides. Its height could not be determined, as
the top was completely broken away and merged with the opening above,
but the bottom, which is also the floor level, is 6 feet 9 inches below
the level of the first roof beams. The doorway of the second story is
preserved only on the northern side. Its bottom, still easily
distinguishable, is 1 foot 6 inches above the bottom of the floor beams.
It was not over 2 feet wide and was about 4 feet high. The upper doorway
is still well preserved, except that the lintels are gone. It is about
three inches narrower at the top than at the bottom and about 4 feet
high.

In addition to its three doorways, all in the eastern wall, the middle
tier