If t is much less than t', while t' is a multiple of t, the note (t+t')/2 disappears, and the notes t+t' and t are heard.
Disk No. 2 has--
On circle No. 1 12 holes, distances 30°
" " 2 36 " " 10°
" " 3 48 " " 7½°
" " 4 60 " " 6°
" " 5 24 " " t= 5°, t'=25°
" " 6 24 " 6° 24°
" " 7 24 " 7½° 22½°
" " 8 24 " 10° 20°
Circle 8 produces the notes of circles 1 and 2; circle 7, those of 1 and 3; circle 6, those of 1 and 4; and circle 5, the note of circle 1 and of its sixth harmonic.
C.
If the same circular arc is divided into m and n equal parts; that is to say, if mt=nt', we obtain the notes m and n.
Disk No. 3 has--
Distances.
On circle No. 1 24 holes, distances 15°
" " 2 24 " " 15° & 27 holes, 13-1/3°
" " 3 24 " " 15° " 30 " 12°
" " 4 24 " " 15° " 32 " 11-1/4°
" " 5 24 " " 15° " 36 " 10°
" " 6 24 " " 15° " 40 " 9°
" " 7 24 " " 15° " 45 " 8°
" " 8 24 " " 15° " 30, 36, & 48 holes
Circle 1 produces a single note, circle 2 a second, circle 3 a third, circle 4 a fourth, 5 a fifth, 6 a sixth, 7 a seventh, and 8 a perfect chord.