Signedon perimeter: Sme D'ARSONVAL Bte S.G.D.G. / DE BRANVILLE & Cie
Inscribedinscribed around the side of the case: Sme D'ARSONVAL Bte S.G.D.G. / DE BRANVILLE & Cie;
stamped on back of case: 1057
FunctionConversion of sound into electrical signal for input to telephone, conversion of electrical signal from telephone into sound
ProvenanceJefferson Laboratory, Physics Department, Harvard University
Published ReferencesThis instrument is described in:
Thomas G. Hedberg, "Catalogue: Telephones, Phonographs and Related Instruments in The Collection of Historical Scientific Instruments at Harvard University." William Andrewes, Project Director (unpublished manuscript, President and Fellows of Harvard College and Thomas G. Hedberg, 1989. Fifth Draft), pp. 62-63.
See also:
William Henry Preece and Julius Maier, The Telephone (London: Whittaker & Co., 1889), pp.52-54.