The Book of the Fair, Hubert Howe Bancroft, 1893
In addition to the Edison exhibits of electrical appliances, forming a portion of the General Electric company’s display, is a section in the southwest gallery containing the instruments of the Edison Manufacturing company; and in this locality, more perhaps than elsewhere in the Exposition, is represented the genius of the inventor. When first it was reported that Edison had constructed a machine which would store conversations, speeches, songs, orchestral music, and any other sounds given into its keeping, and reproduce them at any future time there were many who refused to believe it, and not until his phonographs were displayed at the Paris Exposition of 1889, were all the skeptics converted. Since that date the sheet of tin foil then used for the purpose has given place to the hollow cylinder of wax, upon which, as it revolves, the point of the diaphgram cuts the lines of sound. Apart from the amusement derived from this machine, it is rapidly finding favor among professional and business men, taking the place of the amanuensis, while through its records scientists are enabled to make a more thorough investigation as to the nature of wave sounds.