THE EDISON KINETOGRAPH.
PHOTO-ENGRAVING OF A PORTION OF THE STRIP NEGATIVE OF THE KINETOGRAPH (ACTUAL SIZE).
The “kinetograph,” which is the precursor of the apparatus for showing moving photographs, is of great interest. The kinetograph as first proposed consisted of a clever combination of a photographic camera and the phonograph, by which the words of a speech or play were to be recorded simultaneously with photographic impressions of all the movements of the speakers or actors. The photographic impression is taken at the rate of forty-six per second. The celluloid film upon which the photographic impressions are taken is perforated along one edge with a series of holes, arranged at regular intervals with as much precision as can be secured by means of the finest perforating mechanism, to secure perfect registry. This was found necessary because the phonographic cylinder must be in exact synchronism with the shutter-operating and film-moving devices of the camera. The phonograph and camera mechanisms are driven by the same motor and controlled by the same regulating mechanism. The greatest difficulty was experienced in devising mechanism for the stopping and starting of the film. It was found that the stopping and starting of the film forty-six times a second required about two-thirds of the time, the remainder being utilized for the exposure of the plate. To take these pictures special camera lenses of large aperture had to be constructed. The reproducing apparatus is practically a reversal of the camera; that is, a superior form of projecting lantern is employed which is provided with a strong light, and mechanism for moving forward the strip with an intermittent motion, corresponding exactly to the motion of the negative strip in the camera. The lantern is furnished with a light interrupter which eclipses the light during the brief period required for shifting the film forward to a new position to show the succeeding picture. The apparatus was largely manufactured on a small scale, without the phonograph, for use in railway stations, cigar stores, etc. It was found to be almost impossible to combine the two instruments. In this case the pictures were not projected upon the screen, but were upon a ground-glass plate which the observer looks at.
REYNAUD’S OPTICAL THEATER.
Up to the time of the invention of this theater, the apparatus that produced the synthesis of the successive phases of an action were limited to reproduction upon a very small scale, which can only be enjoyed by a limited group. The object of the optical theater was to provide an apparatus for the reproduction of a series of actions upon a considerable scale. The continuity of the image obtained by the praxinoscope, invented in 1877 by M. Reynaud, had not up to this time been realized by any projecting apparatus. The effect is produced by using a crystalloid band upon which the images are painted as represented at A in our [engraving]. The operator can revolve it in one direction or the other by means of two reels. The images pass before the lantern, B, and are projected by the aid of the objective, C, upon an inclined mirror, M, which projects them upon the transparent screen, E. Another projection lantern, B, causes the appearance on the screen of the scene, amid which appear the characters, which change their posture according as the painted band, A, is revolved by the operator.
