c1919 drawing of triode = book page copied
Toronto. In the early 1900s, some American companies sold fancy copy machines, that relied upon photography, to prosperous companies. Their machines snapped and recorded material directly to photographic paper, which was sometimes developed and fixed automatically.
But not everyone could afford these machines. For example, I was just a little child during the second war and I can remember watching a teacher make handwritten exam sheets using an indelible pencil to write a master sheet in purple.
This sheet was rolled on what looked like a shallow tray of stiff jelly making the words and letters reversed in the “jelly”. A number of blank papers were individually rolled on the “jelly” and peeled off showing purple words and letters now right way around.
In the late 1950s/early 1960s at work, we had a mimeograph machine. A clerk typed instructions on a gestetner master sheet (stencil) that was wrapped around the machine’s drum. These office machines all disappeared when Xerox copy machines came on the market later on. Initially computer-connected scanners were expensive stand alone machines. Today, all-in-one inkjet printers (scan, print, and fax) are dirt cheap squeezing out most of the stand alone scanners.
I made the copy that post a year ago. At the time, I was using a digital camera and copy stand to record negatives and a scanner plus the Image Capture app to copy prints, papers, book pages, etc. A few decades earlier, I used some Leitz accessories to copy papers and book pages both at home and at the Reference Library.
My thanks to friend and fellow PHSC member George Dunbar for sharing this February 1917 article in Electrical Experimenter magazine showing how one company used a camera set up to do copy work. George found the article while researching for photographic history. Below you can see the machine discussed in the article. The lens and prism are on the right facing the copier platform below.
