The above monster machine which is equipped with whirring motors, blinking lights, prisms and cameras ladies and gentlemen, is the genealogical limb of the family tree of our current copy machines and scanners. Indeed, the genealogical tree for the "Photostat" can be attached to the Xerox family tree. Fascinating! In a nutshell: The document to be copied was photographed by one of the on board cameras in this monster machine. A prism reversed the image which was printed on photographic paper which was fed from a huge roll of photo sensitive paper.