Peter Robins emailed through the following, in response to my post on “extra features” in literature, yesterday – Pete Hoskin
Eighteenth-century authors were deep into this sort of thing. Pope was continually reissuing the Dunciad with extras to adapt it to his latest enemies: a new fourth book, a complete set of fake scholarly apparatus. (There are editions with real scholarly notes on Pope’s fake scholarly notes, and real notes of textual variations next to his fake ones.) Something similar happened with Swift’s first major work, A Tale of a Tub – he sliced up unfavourable responses and turned them into deliberately foolish annotations to the next edition.
Some other random ones:
Joe Gould’s Secret, by Joseph Mitchell, a classic of American non-fiction, is all a sort of DVD extra to a New Yorker article called ‘Professor Seagull’.

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