Page:Vitruvius the Ten Books on Architecture.djvu/178

144 into four parts, so that three horizontal ranges of niches may be marked out and constructed: one for the enharmonic, an­other for the chromatic, and the third for the diatonic system. Beginning with the bottom range, let the arrangement be as de­scribed above in the case of a smaller theatre, but on the enhar­monic system.

4. In the middle range, place first at the extreme ends the vessels which give the note of the chromatic hyperbolaeon; next



to them, those which give the chromatic diezeugmenon, a fourth below; third, the chromatic synhemmenon; fourth, the chromatic meson, a fourth below; fifth, the chromatic hypaton, a fourth below; sixth, the paramese, for this is both the concord of the fifth to the chromatic hyperbolaeon, and the concord of the chro­matic synhemmenon.

5. No vessel is to be placed in the middle, for the reason that there is no other note in the chromatic system that forms a natural concord of sound. In the highest division and range of niches, place at the extreme ends vessels fashioned so as to give the note of the diatonic hyper­bolaeon; next, the diatonic diezeugmenon, a fourth below; third, the diatonic synhemmenon; fourth, the diatonic meson, a fourth below; fifth, the diatonic hypaton, a fourth below; sixth, the