irty-three palms and
eleven inches. The space in the centre is hollow and serves as a
passage, which is two squares in height and curves in a continuous
round, with a barrel-shaped vault; and in line with the four entrances
are eight doors, each of which rises in four steps, one of them
leading to the level platform of the cornice of the first basement,
six palms and a half in breadth, and another leading to the inner
cornice that curves round the tribune, eight palms and three-quarters
broad, on which platforms, by each door, you can walk conveniently
both within and without the edifice, and from one entrance to another
in a curve of two hundred and one palms, so that, the sections being
four, the whole circuit comes to be eight hundred and four palms. We
now have to ascend from the level of this basement, upon which rest
the columns and pilasters, and which forms the frieze of the windows
within all the way round, being fourteen palms and one inch in height,
and around it, on the outer side, there is at the foot a short order
of cornice-work, and so also at the top, which does not project more
than ten inches, and all of travertine; and so in the thickness of the
third part, above that on the inner side, which we have described as
fifteen palms thick, there is made in every quarter-section a
staircase, one half of which ascends in one direction and the second
half in another, the width being four palms and a quarter; and this
staircase leads to the level of the columns. Above this level there
begin to rise, in line with the solid parts of the basement, eighteen
large piers all of travertine, each adorned with two columns on the
outer side and pilasters on the inner, as will be described below, and
between the piers are left the spaces where there are to be all the
windows that are to give light to the tribune. These piers, on the
sides pointing towards the central point of the tribune, are
thirty-six palms in extent, and on the front sides nineteen and a
half. Each of them, on the outer side, has two columns, the lowest
dado of which is eight palms and three-quarters broad and one palm and
a half high, the base five palms and eight inches broad and ... palms
and eleven inches high, the shaft of the column forty-three and a half
palms high, five palms and six inches thick at the foot and four palms
and nine inches at the top, the Corinthian capital six palms and a
half high, with the crown of mouldings nine palms. Of th