Part 11 (1/2)

FORUM AT POMPEII

A, Forum. B, Basilica. C, Temple of Apollo. D, D', Market Buildings. E, Latrina. F, City Treasury. G, Memorial Arch. H, Temple of Jupiter. I, Arch of Tiberius. K, Macellum (provision market). L, Sanctuary of the City Lares. M, Temple of Vespasian. N, Building of Eumachia. O, Comitium. P, Office of the Duumvirs. Q, The City Council. R, Office of the Aediles.]

6. But basilicas of the greatest dignity and beauty may also be constructed in the style of that one which I erected, and the building of which I superintended at Fano. Its proportions and symmetrical relations were established as follows. In the middle, the main roof between the columns is 120 feet long and sixty feet wide. Its aisle round the s.p.a.ce beneath the main roof and between the walls and the columns is twenty feet broad. The columns, of unbroken height, measuring with their capitals fifty feet, and being each five feet thick, have behind them pilasters, twenty feet high, two and one half feet broad, and one and one half feet thick, which support the beams on which is carried the upper flooring of the aisles. Above them are other pilasters, eighteen feet high, two feet broad, and a foot thick, which carry the beams supporting the princ.i.p.al raftering and the roof of the aisles, which is brought down lower than the main roof.

[Ill.u.s.tration: _From Durm_

PLAN OF THE BASILICA AT POMPEII]

7. The s.p.a.ces remaining between the beams supported by the pilasters and the columns, are left for windows between the intercolumniations. The columns are: on the breadth of the main roof at each end, four, including the corner columns at right and left; on the long side which is next to the forum, eight, including the same corner columns; on the other side, six, including the corner columns. This is because the two middle columns on that side are omitted, in order not to obstruct the view of the p.r.o.naos of the temple of Augustus (which is built at the middle of the side wall of the basilica, facing the middle of the forum and the temple of Jupiter) and also the tribunal which is in the former temple, shaped as a hemicycle whose curvature is less than a semicircle.

[Ill.u.s.tration: VITRUVIUS' BASILICA AT FANO]

8. The open side of this hemicycle is forty-six feet along the front, and its curvature inwards is fifteen feet, so that those who are standing before the magistrates may not be in the way of the business men in the basilica. Round about, above the columns, are placed the architraves, consisting of three two-foot timbers fastened together.

These return from the columns which stand third on the inner side to the antae which project from the p.r.o.naos, and which touch the edges of the hemicycle at right and left.

9. Above the architraves and regularly dispersed on supports directly over the capitals, piers are placed, three feet high and four feet broad each way. Above them is placed the projecting cornice round about, made of two two-foot timbers. The tie-beams and struts, being placed above them, and directly over the shafts of the columns and the antae and walls of the p.r.o.naos, hold up one gable roof along the entire basilica, and another from the middle of it, over the p.r.o.naos of the temple.

10. Thus the gable tops run in two directions, like the letter T, and give a beautiful effect to the outside and inside of the main roof.

Further, by the omission of an ornamental entablature and of a line of screens and a second tier of columns, troublesome labour is saved and the total cost greatly diminished. On the other hand, the carrying of the columns themselves in unbroken height directly up to the beams that support the main roof, seems to add an air of sumptuousness and dignity to the work.

CHAPTER II

THE TREASURY, PRISON, AND SENATE HOUSE

1. The treasury, prison, and senate house ought to adjoin the forum, but in such a way that their dimensions may be proportionate to those of the forum. Particularly, the senate house should be constructed with special regard to the importance of the town or city. If the building is square, let its height be fixed at one and one half times its breadth; but if it is to be oblong, add together its length and breadth and, having got the total, let half of it be devoted to the height up to the coffered ceiling.

2. Further, the inside walls should be girdled, at a point halfway up their height, with coronae made of woodwork or of stucco. Without these, the voice of men engaged in discussion there will be carried up to the height above, and so be unintelligible to their listeners. But when the walls are girdled with coronae, the voice from below, being detained before rising and becoming lost in the air, will be intelligible to the ear.

CHAPTER III

THE THEATRE: ITS SITE, FOUNDATIONS AND ACOUSTICS

1. After the forum has been arranged, next, for the purpose of seeing plays or festivals of the immortal G.o.ds, a site as healthy as possible should be selected for the theatre, in accordance with what has been written in the first book, on the principles of healthfulness in the sites of cities. For when plays are given, the spectators, with their wives and children, sit through them spell-bound, and their bodies, motionless from enjoyment, have the pores open, into which blowing winds find their way. If these winds come from marshy districts or from other unwholesome quarters, they will introduce noxious exhalations into the system. Hence, such faults will be avoided if the site of the theatre is somewhat carefully selected.

2. We must also beware that it has not a southern exposure. When the sun s.h.i.+nes full upon the rounded part of it, the air, being shut up in the curved enclosure and unable to circulate, stays there and becomes heated; and getting glowing hot it burns up, dries out, and impairs the fluids of the human body. For these reasons, sites which are unwholesome in such respects are to be avoided, and healthy sites selected.

3. The foundation walls will be an easier matter if they are on a hillside; but if they have to be laid on a plain or in a marshy place, solidity must be a.s.sured and substructures built in accordance with what has been written in the third book, on the foundations of temples. Above the foundation walls, the ascending rows of seats, from the substructures up, should be built of stone and marble materials.

4. The curved cross-aisles should be constructed in proportionate relation, it is thought, to the height of the theatre, but not higher than the footway of the pa.s.sage is broad. If they are loftier, they will throw back the voice and drive it away from the upper portion, thus preventing the case-endings of words from reaching with distinct meaning the ears of those who are in the uppermost seats above the cross-aisles.

In short, it should be so contrived that a line drawn from the lowest to the highest seat will touch the top edges and angles of all the seats.

Thus the voice will meet with no obstruction.