Believing this vintage movie camera to be from the 1950s going by the undated paperwork it came with, this Bell & Howell is a double 8mm cine camera. What "double 8mm" means is that it filmed on one side of a 16mm film strip (essentially 8mm) and could then be flipped over to expose the other half (another 8mm). The 16mm film was then split when developed and would give you 50 ft. of exposed 8mm film to play in your projector.
Unlike some of my other vintage finds, I have no intention of filming anything with this one. I was really impressed because this camera was in practically brand new condition and included the original manual for only $20. For now this vintage Bell & Howell will make a nice prop.