lambanomenos, a fourth
below; in the middle, the note mese, for this is both the octave to
proslambanomenos, and the concord of the fifth to the diatonic hypaton.

6. Whoever wishes to carry out these principles with ease, has only to
consult the scheme at the end of this book, drawn up in accordance with
the laws of music. It was left by Aristoxenus, who with great ability
and labour classified and arranged in it the different modes. In
accordance with it, and by giving heed to these theories, one can easily
bring a theatre to perfection, from the point of view of the nature of
the voice, so as to give pleasure to the audience.

7. Somebody will perhaps say that many theatres are built every year in
Rome, and that in them no attention at all is paid to these principles;
but he will be in error, from the fact that all our public theatres made
of wood contain a great deal of boarding, which must be resonant. This
may be observed from the behaviour of those who sing to the lyre, who,
when they wish to sing in a higher key, turn towards the folding doors
on the stage, and thus by their aid are reinforced with a sound in
harmony with the voice. But when theatres are built of solid materials
like masonry, stone, or marble, which cannot be resonant, then the
principles of the "echea" must be applied.

8. If, however, it is asked in what theatre these vessels have been
employed, we cannot point to any in Rome itself, but only to those in
the districts of Italy and in a good many Greek states. We have also the
evidence of Lucius Mummius, who, after destroying the theatre in
Corinth, brought its bronze vessels to Rome, and made a dedicatory
offering at the temple of Luna with the money obtained from the sale of
them. Besides, many skilful architects, in constructing theatres in
small towns, have, for lack of means, taken large jars made of clay, but
similarly resonant, and have produced very advantageous results by
arranging them on the principles described.

CHAPTER VI

PLAN OF THE THEATRE

1. The plan of the theatre itself is to be constructed as follows.
Having fixed upon the principal centre, draw a line of circumference
equivalent to what is to be the perimeter at the bottom, and in it
inscribe four equilateral triangles, at equal distances apart and
touching the boundary line of the circle, as the astrologers do in a
figure of the twelve signs of the zodiac, when they are making
computations from the musical