Yep - the computer typeface snuck in there reminded me a bit of Nick Wilding's discovery of a forged Galileo book. There was a two-character chunk of a supposedly letter-press printed word that had blurred in the way things do when you bump a scanner. It turned out it was a forgery created just a decade before, but done with such remarkable expertise that it fooled even the leading Galileo and rare book experts. It's really a fascinating story:

http://www.newyorker.com/magazine/2013/12/16/a-very-rare-boo...