ing as from a centre, and striking against the cavity of 
each vase, will sound with increased clearness and har¬ 
mony, from its unison with one or other of them. If. 
however, the theatre be on a larger scale, the height is to 
be divided into four parts, so that three ranges of cavities 
may be provided, one for harmonic, the second for chroma¬ 
tic, and the third for diatonic vases. That nearest the bot¬ 
tom is for the harmonic genus as above described, for a 
lesser theatre. In the middle range on the extremities. 
vases producing the chromatic hyperbolæeon are placed: in 
the second cavities the chromatic diezeugmenon, a fourth 
from the last : in the third, at another interval of a fourth. 
the chromatic synèmmenon: in the fourth, the chromatic 
meson, another fourth: in the fifth, the chromatic hy¬ 
paton, another fourth: in the sixth, the paramesè, which 
is a fifth to the chromatic hyperbolæon, and a fourth to 
the chromatic meson. In the centre none are to be 
placed, because no other sound in the chromatic genus 
can be in consonance therewith. In the upper division 
and range of the cavities, the vases on the extremities are 
constructed to produce the tones of the diatonic hyperbo¬ 
læon: in the next cavities, those of the diatonic diezeugme¬ 
non, a fourth: in the third, of the diatonic synèmmenon, a 
fourth : in the fourth, of the diatonic meson, a fourth: in 
the fifth, of the diatonic hypaton, a fourth : in the sixth, 
proslambanomenos, a fourth : in the centre, mesè, be¬ 
tween which and proslambanomenos is an octave, and a 
fifth between it and the diatonic hypaton. He who is de¬ 
sirous of more fully understanding these matters, must refer 
to the musical diagram at the end of the book, which is 
that left to us by Aristoxenes, who with much intelligence 
and labour, formed a general scale of the tones. Hence,