By the help of the phonograph we have continued the investigation described in a previous Communication (Proc. R.S.E., p. 582), and have now obtained about two hundred magnified traces of the phonographic records of vowel sounds spoken and sung by various voices, and of these sixty-five have been already subjected to harmonic analysis, extending as far as the sixth partial tone. In each case the results have been accepted as satisfactory only when, after the magnified trace had been obtained, the record on the tinfoil of the phonograph still gave the vowel sound satisfactorily. Our attention has hitherto been almost exclusively directed to the vowels u (the vowel sound in “food,”) and o (as in “oh,”) both of which are well spoken by the phonograph.