It's a mourning book ... with a xylographic title page, that is, a title page
in which white lettering appears on a black background. But when the
microfilm was being processed, someone clearly didn't believe what they
were seeing and they assumed it was a mistake, that it should be black on
white, and so they reversed the negative, producing a facsimile of a book
that doesn't exist.
-- Sarah Werner,
"where material book culture meets digital humanities."
Wynken de Worde.
http://sarahwerner.net/blog/index.php/2012/04/where-material-book-culture-meets-digital-humanities/