Pallophotophone

Collier's New Encyclopedia (1921)

an apparatus for recording and reproducing sounds photographically. The human voice or other sound is made to cause the oscillation of a delicate mirror and in this way to affect a beam of light reflected from the mirror to a photographic film in continuous motion. The sound is reproduced by moving the developed film in front of a delicate electrical device whose energy is affected by the intensity of the light falling upon it. The electrical current with these impressed variations is in turn transformed to sound as in ordinary telephony or as in radio with loud-speaking devices. The pallophotophone has already been used to make records for broadcasting from radio stations. Its possible applications in the recording and reproducing of long speeches, lectures, etc., are obvious, while it also makes possible the simulciple was asserted by the United States at the end of the nineteenth century, when Secretary Hay addressed the Powers in protest against the establishment in China of exclusive commercial and other rights within their so-called spheres of influence. In general, the Powers assented to the principle, which, however, remained largely unapplied in practice until given a new and more definite standing by the treaties and resolves concerning China agreed upon by the Washington Conference, February, 1922. At the Near Eastern Conference held at Lausanne, 1922-23, the American Government strongly demanded the acceptance of the principle of the open door in Turkey. The Turkish representatives expressed their approval, and the other Powers in general assented. taneous recording of pictures and sounds on the same photographic film, thus answering the main problem of the talking motion picture.