Alexander Graham BELL, Ph.D., "On the Production 
and Reproduction of Sound by Light", American Journal of 
Sciences
, Third Series, vol. XX, n°118, Oct. 1880, pp. 305- 324.

[Read before the American Association for the Advancement 
of Science, in Boston, August 27, 1880]

Egalement publié sous le titre "Selenium and the Photophone", 
in Nature, Sept. 23, 1880.

 


Notice

[Traduction en français de larges extraits de cet article et commentaires dans Th. du MONCEL, "Reproduction des sons sous l'influence de la lumière. Photophone de M. Graham Bell", La Lumière électrique, Paris, 1er octobre 1880]

 


  IN bringing before you some discoveries made by Mr. Sumner Tainter and myself, which have resulted in the construction of apparatus for the production and reproduction of sound by means of light, it is necessary to explain the state of knowledge which formed the starting point of our experiments.

    I shall first describe tkat remarkable substance "selenium",  and the manipulations devised by previous experimenters ; but the final result of our researches has widened the class of substances sensitive to light vibrations, until we can propound the fact of such sensitiveness being a general property of all  matter.

    We have found this property in gold, silver, platinum, iron, steel, brass, copper, zinc, lead, antimony, german-silver, Jenkin's metal, Babbitt's metal, ivory, celluloid, gutta-percha, hard rubber, soft vulcanized. rubber, paper, parchment, wood, mica, and silvered glass; and the only substances from which we have not obtained results, are carbon and thin microscope glass. (1)

                                                                                                              

(1) Later experiments have shown that these are not exceptions.

 

 

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