The Carbonel Phonograph

From the printed record of American Graphophone Company vs. United States Phonograph Company.  Engineering, Vol. 27, p. 326.
  April 18, 1879.

            The Phonograph.--the Abbé Carbonel, of the Belsunce School, Marseilles, has been experimenting with the phonograph, and concludes that the recording and rehearsing diaphragms should be distinct, the former having a very sonorous plate operating on very stiff, hard foil, the latter a delicate membrane like that of the ear.  The foil could be made from a copper band thinly coated with wax to take the impression, and corroded afterwards by acid so as to obtain a hard metal cast; but this is necessarily a defective process.  The Abbé, therefore, employs albumen spread upon paper or other base, instead of the wax applied to the copper.  The soft albumen record is afterward hardened in a well-known manner, and a hard matrix, whose dints vary in depth with the intensity of the sound, is obtained.  As a means of reproducing the sounds he suggests the use of Savart's wheel instead of a vibrating plate.

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