We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
MOTION PICTURE PROJECTION PROTECTION OF FILM FROM IGNITION The film is now so surrounded and framed in metal that if it does inflame the center of the film alone will burn, a hole thus being made through the film, leaving the edges intact. As the only danger to be apprehended from a burning film is the panic of the audience, if the combustion can be restricted to less than a square inch of thin film, the vividness of whose combustion is restrained to some extent by the gelatine emulsion which carries the pictures on it, would not seem adequate to frighten a theatre full of people. But from every standpoint the burning of any part of the film is to be avoided by every possible precaution. It is better to provide for its prevention than to rely on the safety devices to prevent it cluing harm, when it occi An operator will take the ground that a film will never do inure than burn out in the center. This is a comforting idea, but it is better to contemplate the possibility of the whole film going a half explosion. 1 and to take measures to make nition of the film as nearly impossible as can be done. THK FIRE SHUTTER FILM The usual way of guarding against long exposure of the film to the heat of the projected rays is by a shutter hinged at the top, which is heM up. so as to leave the path of the rays clear, by a centrifugal mechanism. Thi> operates to hold the shutter up and out of the path of the light as long as the handle of the machine is turned. If anything operates to stop the progress of the ma- chine and thereby to arrot the progress of the film, so that it is stationary, the centrifugal apparatus ceases to work, and the shutter drops between film and condenser, cutting off all heat from the film. The construction of this type of fire shutter will be given in some detail a little later, with some prominent construct^ ; the base of the description. It will be seen that the centrifugal shutters, as they may be called, operate entirely by the motion of the machinery of the projector. But there is a case of exposure of the film to the heat, which may occur without the motion of the projection apparatus being arrested. 264