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 deg.
" " 2 36 " " 10 deg.
" " 3 48 " " 71/2 deg.
" " 4 60 " " 6 deg.
" " 5 24 " " t= 5 deg., t'=25 deg.
" " 6 24 " 6 deg. 24 deg.
" " 7 24 " 71/2 deg. 221/2 deg.
" " 8 24 " 10 deg. 20 deg.

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 deg.
" " 2 24 " " 15 deg. & 27 holes, 13-1/3 deg.
" " 3 24 " " 15 deg. " 30 " 12 deg.
" " 4 24 " " 15 deg. " 32 " 11-1/4 deg.