6The following are the rules for door-ways of temples, and for their dressings (antepagmenta). First the species is to be considered: this is Doric, Ionic, or Attic. The Doric is constructed with these proportions. The top of the cornice, which is above the upper dressing, is to be level with the top of the capitals in the pronaos. The aperture of the door is determined as follows. The height from the pavement to the lacunaria is to be divided into three parts and a half, of which two constitute the height of the doors. The height thus obtained is to be divided into twelve parts, of which five and a half are given to the width of the bottom part of the door. This is diminished towards the top, equal to one third of the dressing, if the height be not more than sixteen feet. From sixteen feet to twenty-five the upper part of the opening is contracted one fourth part of the dressing. From twenty-five to thirty feet the upper part is contracted one-eighth of the dressing. Those that are higher should have their sides vertical.
6For the doorways of temples and their casings the rules are as follows, first determining of what style they are to be. The styles of portals are Doric, Ionic, and Attic.
In the Doric, the symmetrical proportions are distinguished by the following rules. Let the top of the corona, which is laid above the casing, be on a level with the tops of the capitals of the columns in the pronaos. The aperture of the doorway should be determined by dividing the height of the temple, from floor to coffered ceiling, into three and one half parts and letting two and one half thereof constitute the height of the aperture of the folding doors. Let this in turn be divided into twelve parts, and let five and a half of these form the width of the bottom of the aperture. At the top, this width should be diminished, if the aperture is sixteen feet in height, by one third the width of the door-jamb; if the aperture is from sixteen to twenty-five feet, let the upper part of it be diminished by one quarter of the jamb; if from twenty-five to thirty feet, let the top be diminished by one eighth of the jamb. Other and higher apertures should, as it seems, have their sides perpendicular.