JF Ptak Science Books
So, this is clearly photographic film, and seems to be a picture of something, but a picture of what? This is a positive of a negative, and the major hint here is that the year it was made was 1923.
[Source: private collection]
This is a three-frame snippet from what is evidently among the first true talking motion pictures. It was engineered by Lee de Forest (1873-1961, inventor of the first triode vacuum tube, the Audion, in 1906, earning him the sobriquet of "the Father of radio") and shown in NYC in December, 1923, which was nearly three years ahead of what is commonly thought to be the first 'talkie", the Al Jolson vehicle The Jazz Singer (1926). Although not truly a first/first, The Jazz Singer was certainly the first mass-distributed talkie, and the first monetarily successful one. The de Forest film was a sound-on-film motion picture, which represented the culmination of efforts to reproduce sound in the movies by many different practices, none nearly as successful as synching up the sound/film so that there was no displacement between the two. Here wwe see the sound as the horizontal bars running along the left-side of the film, which in effect is the visualization of the medium of the movie industry to come. (The attempts at sound motion pictures are almost as old as the pictures themselves, the earliest version being simple recordings of the audio on a disk, then played along with the showing of the movie in two different systems. Compared to nothing at all, these advances were very notable, especially if the timing between the two elements wasn't off by very much. These of course failed entirely in the face of the sound-on-film advancement.)
The breakthrough by de Forest turns out to be one of those stories where the inventor and brains behind the technological advance tries to implement and market the thing themselves, only to fail at the economic aspects of a great invention.