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From: smoulthrop@UBmail.ubalt.edu
Subject: A history of the interstitial, July 2004.
Many apologies for taking so long to answer, and more apologies still if this is too late to be useful.
The term "interstitial" was memorably used by Michael Joyce in _Of Two Minds_ (U. Michigan Press, 1995) to describe more or less elliptical or digressive sections of the book placed between two more focused or thematic chunks. Michael had earlier used the term in one or more of his essays ("What the Fish Lady Saw," I think) (Dl: 1995), to name a chunk of narrative sandwiched between two slices of critical essay.
To me, Michael's usage always seemed more than arbitrary or technical, really almost metaphysical or spiritual -- as if the standing-between stood for something deeply related to the truth or purpose of what we were doing with hypertext, where as I take it we are always betweening something.
So I absconded with the term when thinking about cybertext, specifically about the Miller Brothers' _Riven_, the sequel to _MYST_. I used the term to talk about both _Riven_ and comic-book temporality in "Misadventure: Future Fiction and the New Networks," which appeared in a journal called_Style_, and can be found online at http://iat.ubalt.edu/moulthrop/essays/misadventure/ .
By the way, when I was checking the references I was delighted to find thatone of Michael's "interstitials" in _Of Two Minds_ is an introduction to_Victory Garden_. Maybe all too small a world, but there's the circuit anyway.
Hope this is some use, late as it is.
Stuart