COLONNADES AND WALKS

1. Colonnades must be constructed behind the scaena, so that when sudden
showers interrupt plays, the people may have somewhere to retire from
the theatre, and so that there may be room for the preparation of all
the outfit of the stage. Such places, for instance, are the colonnades
of Pompey, and also, in Athens, the colonnades of Eumenes and the fane
of Father Bacchus; also, as you leave the theatre, the music hall which
Themistocles surrounded with stone columns, and roofed with the yards
and masts of ships captured from the Persians. It was burned during the
war with Mithridates, and afterwards restored by King Ariobarzanes. At
Smyrna there is the Stratoniceum, at Tralles, a colonnade on each side
of the scaena above the race course, and in other cities which have had
careful architects there are colonnades and walks about the theatres.

2. The approved way of building them requires that they should be
double, and have Doric columns on the outside, with the architraves and
their ornaments finished according to the law of modular proportion. The
approved depth for them requires that the depth, from the lower part of
the outermost columns to the columns in the middle, and from the middle
columns to the wall enclosing the walk under the colonnade, should be
equal to the height of the outer columns. Let the middle columns be one
fifth higher than the outer columns, and designed in the Ionic or
Corinthian style.

3. The columns will not be subject to the same rules of symmetry and
proportion which I prescribed in the case of sanctuaries; for the
dignity which ought to be their quality in temples of the gods is one
thing, but their elegance in colonnades and other public works is quite
another. Hence, if the columns are to be of the Doric order, let their
height, including the capital, be measured off into fifteen parts. Of
these parts, let one be fixed upon to form the module, and in
accordance with this module the whole work is to be developed. Let the
thickness of the columns at the bottom be two modules; an
intercolumniation, five and a half modules; the height of a column,
excluding the capital, fourteen modules; the capital, one module in
height and two and one sixth modules in breadth. Let the modular
proportions of the rest of the work be carried out as written in the
fourth book in the case of temples.

4. But if the columns are to be Ionic, let the shaft, excluding base and
capital