"Explains how a projectionist can put on a professional 16 mm. sound film showing by observing a check list of hints and safeguards. Emphzsizes the importance of a pre-showing check of the kind and source of power, light conrol facilities, and ventilations; of correct set-up of projector, speaker, and screen; placement and plugging of cords; adjustment of focus, screen size, tone and volume controls; and a final check for clean aperture before threading." - Summary from Worldcat.