that would be practical from the standpoints of weight, size, use,
and cost indicated a small negative size, as did the number of supplementary features that were desirable as integral parts of the camera rather than as accessories. Final choice rested on the 35mm film width and the 24 x 36mm format, because of the wide range of emulsions available for this size, widespread standardization on the convenient 2 x 2-inch projection slides it makes possible, similar standardization in projectors, and convenient accommodation in precision enlarging equipment.
        The number of these specialised negative emulsions-in both black and white and color-as well as the different types of pictures and different conditions under which successive groups of pictures are made-indicated some practical and safe means of changing quickly from one emulsion to another.

An achievement of cooperative planning, design, and manufacture
        Once these determining factors were evaluated and interpreted into practicability, experts went to work to put them into tangible form. Lens scientists, camera, designers, mechanical engineers, authorities in range-finder and view-winder optics, production engineers cognizant of the possibilities of new precision manufacturing . . . these and many others started "from scratch" to develop the camera specified. Working in

closest cooperation with one an-
other, they also coordinated their efforts with the activities of divisions producing the films, accessories, enlargers used in contemporary advanced photography. This coordination was a prerequisite because of the extreme precision and wide scope determined upon . . . because of the intimate interrelationship of the complex
mechanisms required . . . because of the interdependence necessary