Gestetner duplicator
The Gestener duplicator was an American redesign of a 19th century invention by Hungarian, Gustave Gestener.
The principle of operation is that a specially prepared 'stencil' is mounted on an inking bed that could be repeatedly tracked around an upper and lower drum as the machine's handle is turned. They were basically a hand operated machine although electrified versions were also available where larger runs were required. Blank paper is fed from an in-tray on the left of the machine, under the lower drum where the stencil is forced against the paper transferring ink through the cuts. The 'printed' copy of paper is fed to an out-tray on the right of the machine. As the stencil goes over the top drum, it is supplied with a fresh coat of ink and the cycle repeats. A single stencil could produce hundreds of copies, and with care could even be stored for reuse if required.
The Stencils were a proprietry waxed tissue paper with a stronger mounting strip at one end which had perforation that fitted over a matching pattern on the rotating ink bed. You needed to pay careful attention to fitting the stencil to the machine to avoid creases and tears. Following the invention of the typewriter, that became the main way to 'cut' a stencil. Stencils could also be cut by hand using a special stylus which had a small wheel on the end and as it rotated, cut small impressions into the wax. Some creative uses were made to harness full use of this technology with photos also able to be transferred to stencil using special machines. A small range of ink colours was available but once a machine had been loaded with ink, the colour was usually never changed.
This technology quickly disappeared during the 1970's and 80's as the modern photocopier was developed.