§ 22 A Constructive Device to Avoid Charging Architraves113
Having set up the columns, and above the capitals the architraves, which are brought into contact the one with the other above the middle axis of the column, the builder proceeds to make a square block or die (D, D, Fig. 5). For example, if the column be a braccio thick and the architraves the same in width114 and height, let the die in the frieze be made equal to them; but in front let there remain an eighth in the face for the vertical joint, and let another eighth or more have a sinking into the die on each side, bevelled to an angle of 45°, Fig. 5 (1). Then since the frieze in each intercolumniation is in three pieces (B, A, B), let the two at the sides (B, B) have bevelled projections in the opposite sense to the sinkings, increasing from within outwards, Fig. 5 (2), so that each may be mortised in the die and be keyed after the manner of an arch, and in the front the amount of the eighth must bond vertically; while the part on the other side must do the same to the other die. And so above the column115 one must arrange that the piece in the middle of the said frieze closes within and is recessed in quarter-round form up to the middle, while the other half must be squared and straight and set with an empty space below, in order that it may hold as does an arch, the wall on the external face appearing worked with vertical joints.116 Do not let the stones of the said frieze rest on the architrave, but let a finger’s breadth be between them; in this way, making an arch, the frieze comes to support itself and does not burden the architrave. Afterwards make on the inside, for filling up the said frieze, a flat arch of bricks as high as the frieze, that stretches from die to die above the columns. Then make a piece of cornice as wide as the die117 above the columns, which has the joints in front like those of the frieze, and within let the said cornice be keyed like the blocks of the frieze, care being taken to make the cornice, as the frieze, in three pieces, of which the two at the sides hold from within the middle piece of the cornice above the die of the frieze,118 and mind that the middle piece of the cornice, C, C, slips down into the sinkings so as to span the void, and unites the two pieces at the sides so as to lock them in the form of an arch. In this fashion everyone can see that the frieze sustains itself, as does the cornice, which rests almost entirely on the arch of bricks.119 Thus one thing helping another, it comes about that the architrave does not sustain any but its own weight, nor is there danger of its ever being broken by too heavy a load. Because experience shows this method to be the most sure, I have wished to make particular mention of it, for the convenience and benefit of all; especially as I know that when the frieze and the cornice were put above the architrave as was the practice of the ancients, the latter broke in course of time, possibly on account of an earthquake or other accident, the arch of discharge which was introduced above the cornice not being sufficient to preserve it. But throwing the arches above the cornices made in this form, and linking them together with iron, as usual,120 secures the whole from every danger and makes the building endure eternally.
Returning to the matter in hand, let us explain then that this fashion of work may be used by itself alone, or can be employed in the second floor from the ground level, above the Rustic Order, or it can be put higher up above another variety of Order such as Ionic, Corinthian or Composite, in the manner shown by the ancients in the Colosseum in Rome, in which arrangement they used skill and judgement. The Romans, having triumphed not only over the Greeks but over the whole world, put the Composite Order at the top, of which Order the Tuscans have composed many varieties. They placed it above all, as superior in force, grace, and beauty, and as more striking than the others, to be a crown to the building; for to be adorned with beautiful members gives to the work an honourable completion and leaves nothing more to be desired.