The G. E. M. Camera (Fig. 59) is a very light self-contained clockwork-drive camera taking 36 pictures six inches square. The film is unrolled from a small-diameter feeding roller on to a large-diameter receiving roller to which the driving mechanism is attached. By this means approximately equal spacing of pictures on the film is assured. The film is held flat by continuous contact with a glass plate, which is made of yellow glass, so that it serves at the same time as a color filter.
Fig. 59. - G. E. M. automatic film camera.
The lens—of 8 to 12 inch focus—is equipped with a single speed between-the-lens shutter. The operation of the camera is entirely automatic. The interval between pictures is controlled by varying the clockwork speed, through a lever on the outside of the camera box. Protection of the camera from vibration is sought by supporting it on four spring cushions mounted on a solid frame, to which the camera is held by spiral springs attached to its sides.