everything with his pencil and camera lucida while
Doctor Cabot and myself took up the Daguerreotype; and, in order to
ensure the utmost accuracy, the Daguerreotype views were placed with
the drawings in the hands of the engravers for their guidance.

[Engraving 13: Ground Plan of the Casa del Gobernador]

The ground plan of the Casa del Gobernador is represented in the
engraving below. It has eleven doorways in front and one at each end.
The doors are all gone, and the wooden lintels over them have fallen.
The interior is divided longitudinally by a wall into two corridors,
and these again, by cross walls or partitions, into oblong rooms. Every
pair of these rooms, the front and back, communicate by a doorway
exactly opposite a corresponding doorway in front.

The principal apartments in the centre, with three doorways opening
upon the terrace, are sixty feet long. The one in front is eleven feet
six inches wide, and the inner one thirteen feet The former is
twenty-three feet high to the top of the arch, and the other twenty-two
feet. The latter has but one door of entrance from the front room, and
except this it has no door or aperture of any kind, so that at the ends
it is dark and damp, as is the case with all the inner rooms. In these
two apartments we took up our abode.

The walls are constructed of square, smooth blocks of stone, and on
each side of the doorway are the remains of stone rings fixed in the
walls with shafts, which no doubt had some connexion, with the support
of the doors. The floors were of cement, in some places hard, but, by
long exposure, broken, and now crumbling under the feet.

The ceiling forms a triangular arch, as at Palenque, without the
keystone. The support is made by stones overlapping, and bevilled so as
to present a smooth surface, and within about a foot of the point of
contact covered by a layer of flat stones. Across the arch were beams
of wood, the ends built in the wall on each side, which had probably
been used for the support of the arch while the building was in
progress.

For the rest, I refer to the plan, mentioning only one circumstance. In
working out the plan on the spot, it was found that the back wall,
throughout its whole length of two hundred and seventy feet, was nine
feet thick, which was nearly equal to the width of the front apartment.
Such thickness was not necessary for the support of the building, and,
supposing it might contain some hidden passages, we