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Background: In the early 1800s, somewhat before the invention of the Xerox machine and the iPhone camera, the only way to copy a document was to actually write it twice. That is, UNLESS you owned a newfangled “polygraph” (https://en.wikipedia.org/wiki/Polygraph_(duplicating_device) ), which enabled writing with two mechanically linked pens simultaneously (Figure 1). Proposal: This same technology…