Thomas Edison discovered the Electric pen (perforator/stencil maker) in 1876. His electric pen was used to create multiple copies of a document by passing over the stencil at a rate approximate to 50 cycles per second perforating the layers below creating duplicates under the original.  The machaninc of the Edison perforator have the same components that you would see in telephones, door bells and even Morse code machines.  The first machine was credited to Southernland Macdonald whom predated Edison by a few years.