2The circumsonant are those where the voice, wandering round, is at last retained in the centre, where it is dissipated, and, the final syllables being lost, the meaning of words is not distinguished. The resonant are those in which the voice, striking against some hard body, is echoed in the last syllables so that they appear doubled. Lastly, the consonant are those in which the voice, aided by something below, falls on the ear with great distinctness of words. Hence, if due care be taken in the choice of the situation, the effect of the voice will be improved, and the utility of the theatre increased. The differences of the figures consist in this, that those formed by means of squares are used by the Greeks, and those formed by means of triangles by the Latins. He who attends to these precepts will be enabled to erect a theatre in a perfect manner.
2The circumsonant are those in which the voice spreads all round, and then is forced into the middle, where it dissolves, the case-endings are not heard, and it dies away there in sounds of indistinct meaning. The resonant are those in which it comes into contact with some solid substance and recoils, thus producing an echo, and making the terminations of cases sound double. The consonant are those in which it is supported from below, increases as it goes up, and reaches the ears in words which are distinct and clear in tone. Hence, if there has been careful attention in the selection of the site, the effect of the voice will, through this precaution, be perfectly suited to the purposes of a theatre.
The drawings of the plans may be distinguished from each other by this difference, that theatres designed from squares are meant to be used by Greeks, while Roman theatres are designed from equilateral triangles. Whoever is willing to follow these directions will be able to construct perfectly correct theatres.