ought to be as broad as they are high. But in violation of this rule, at the corner columns triglyphs are placed at the outside edges and not corresponding to the centre of the columns. Hence the metopes next to the corner columns do not come out perfectly square, but are too broad by half the width of a triglyph. Those who would make the metopes all alike, make the outermost intercolumniations narrower by half the width of a triglyph. But the result is faulty, whether it is attained by broader metopes or narrower intercolumniations. For this reason, the ancients appear to have avoided the scheme of the Doric order in their temples.
3. However, since our plan calls for it, we set it forth as we have received it from our teachers, so that if anybody cares to set to work with attention to these laws, he may find the proportions stated by which he can construct correct and faultless examples of temples in the Doric fashion.
Let the front of a Doric temple, at the place where the columns are put up, be divided, if it is to be tetrastyle, into twenty-seven parts; if hexastyle, into forty-two. One of these parts will be the module (in Greek ἐμβάτης); and this module once fixed, all the parts of the work are adjusted by means of calculations based upon it.
4. The thickness of the columns will be two modules, and their height, including the capitals, fourteen. The height of a capital will be one module, and its breadth two and one sixth modules. Let the height of the capital be divided into three parts, of which one will form the abacus with its cymatium, the second the echinus with its annulets, and the third the necking. The diminution of the column should be the same as described for Ionic columns in the third book. The height of the architrave, including taenia and guttae, is one module, and of the taenia, one seventh of a module. The guttae, extending as wide as the triglyphs and beneath the taenia, should hang down for one sixth of a module, including their regula. The depth of the architrave on its under side should answer to the necking at the top of the column. Above
