This post is a collaboration between Adam G. Hooks (U. of Iowa) and Marissa Nicosia (UPenn) — and is cross-posted at Adam’s blog anchora and the Penn Libraries’ blog Unique at Penn. This started as another post in Adam’s “Breaking Apart” series, which has recently focused on leaf books (see here, here, and here). As you’ll see below, our collaboration started when we began comparing our libraries’ respective copies of the same leaf book.
This is a story of a bibliographic reference book that does not simply describe old books, but actually incorporates original leaves from those books, making it a unique and rare work in and of itself. Falconer Madan’s study of Oxford printing, The Early Oxford Press (1895), catalogs and provides bibliographical descriptions of books produced in Oxford up to 1640. As he had outlined two years before, in an address to the Bibliographical Society, a “perfect bibliography” would not only attend to the physical aspects of a book, but would attend to the historical and cultural context, as well–or, in Madan’s words, it would “set before the student so much of the life of a book as would give him … the place of the volume in the literature of its subject” (“On Method in Bibliography,” 91). As such, a bibliographer should “never rest content with the technical description only.” Madan went even further than this, though, arguing that “if possible, leaves from real books should be bound in each copy, to illustrate the actual printing of each decade or each quarter century” (98).
And indeed, Madan’s ambition was (at least in part) fulfilled: the first edition of The Early Oxford Press included specimen leaves from actual sixteenth and seventeenth century printed books.  Though some of Madan’s illustrative examples are facsimiles intended to exemplify different styles of book production, each copy of his book also included a sampling of rare material. In the preface Madan provides a rationale for the inclusion of this rare material, one of the “features of novelty” of his work. In his account, “actual pages of books printed at Oxford” were inserted, pages which were selected, as he is careful to state, “from works which are cheap and common” (vii). At this point Madan inserts a footnote, further justifying his method in opposition to the insertion of “separate leaves from rare and costly books” in a previous work (a collection of leaves from Swedish liturgies from 1879) which, as he curtly notes, was “a practice which cannot be approved.”
As Christopher de Hamel notes in his consideration of the often dubious ethics of leaf books, “most writers would say that the leaves being dispersed derived from a book that was already defective and fragmentary” (11). In Madan’s case, the books may or may not have been “defective and fragmentary” (although as you’ll see in a moment, there was a particular kind of damage in one of the books he used) but nevertheless they were “cheap and common,” which alone justifies breaking them apart. This makes Madan’s leaf book a limit case of the genre (especially since it is primarily a reference work) and de Hamel duly notes that Madan’s “austere bibliography” is “quite the least bibliophilic leaf book ever issued” (11).
Breaking Apart / Collaborating
When Adam posted on twitter that he had found a copy of a book on the open stacks with sixteenth- and seventeenth-century leaves (and later found two more copies of the book, one of which was also on the open stacks), I promised (on twitter) to track down Penn’s copy to see if ours also included rare materials. Sure enough, it was also on the open stacks with the rare leaves intact. On closer examination of two of the Iowa and Penn copies, Adam and I were able to establish a few points of contact. When we realized we had the chance to bring together leaves from texts that had been broken apart, we decided to collaborate.
As it happens, two of the Iowa copies and the Penn copy include leaves from the same books. According to the plan Madan outlines in his preface, the extracted leaves were systematically grouped and divided. The first 700 copies of the print-run included three leaves; beyond 700, at least one leaf was promised. Madan also provides a reference list of books from which these exemplary leaves were drawn.
Penn’s copy (#366) and Iowa’s (# 371 and #456) are from the same subset (nos. 323-500) of the first 700 copies of Madan’s book. The third Iowa copy (#27) is from the first subset (nos. 1-200). 
Here’s a list of the books from which the leaves in our shared copies are taken:
Madan’s selections suggest that the Oxford printing trade in this era could be represented by a theological work in English (Ursinus), a text on logic in Latin (Sanderson), and a treatise on the value of proverbs in Latin (Reusner). (The Fuller and Carpenter books also fit this model). This is perhaps unsurprising–the Oxford trade would naturally cater to a primarily academic audience, focusing on popular or useful works which would need to be reprinted on a regular basis, while relying on the import trade, from both London and the Continent, for books which were less popular, less useful, or simply extra-curricular.
On closer observation, however, the Penn copy and two of the Iowa copies share more than just leaves from the same books–they include leaves from the same copy of the same book. The extracted leaves from Ursinus in all three copies bear evidence of the industrious work of bookworms. 
A very hungry bookworm started somewhere before page 733 (Penn’s copy) and ate its way through pages 743 and 915 (Iowa’s copies).
In its original state, this copy of Ursinus’s The Summe of Christian Religion was consumed along a trajectory that became impossible when the book was disbound. Linda Charnes suggests wormholes as a metaphor for understanding temporality in our relationship to early modernity and the work of time within early modernity itself. She asks, “Is it possible to create a transmissible methodology out of reading for temporal ‘wormholes’?” (para. 2) By reading the wormholes in the scattered leaves of this copy of Ursinus, we are confronted with persistent reminders of the former state of these leaves, bound together within the boards of a late-sixteenth century book printed in Oxford. Just as Charnes’s metaphor simultaneously invokes holes made by actual worms and events where the space-time continuum collapses, encountering the wormholes shared between two copies of a bibliographical handbook held at two research universities forces us to consider the materialities of the original book and the leaves rebound at Madan’s discretion. Indeed, in comparing these copies of Madan’s book we are brought to a greater understanding of the original books, and thus fulfill part of Madan’s original mission of reaching a greater understanding of early Oxford printing, if through a circuitous path. These books may have been broken apart–and they may still be housed apart–but they have been brought back together again here in the digital ether.
 Penn copy is part of a three-volume set with volumes on the years 1641-1650 and 1651-1680. Volumes 2 and 3 do not contain any rare materials. World Cat records 206 copies of Madan’s Early Oxford Press held in US and International Research Libraries, but this count does not distinguish between individual volumes in the series or reprints.
Fuller, Nicholas, Miscellaneorum Theologicorum (1616; STC 11461)
Carpenter, Nathaniel, Philosophia Libera (1636; STC 4679)
If you’re interested in bookworms, Blair Hedges has done some fascinating research on the traces they leave in early modern woodblocks. http://science.psu.edu/news-and-events/2012-news/Hedges11-2012
Charnes, Linda. “Reading for the Wormholes: Micro-Periods from the Future” Early Modern Culture (Special Issue, 2007) http://emc.eserver.org/1-6/charnes.html
de Hamel, Christopher. “The Leaf Book” in Disbound and Dispersed: The Leaf Book Considered, Christopher de Hamel and Joel Silver, with John P. Chalmers, Daniel W. Mosser, and Michael Thompson (Chicago: The Caxton Club, 2005).
Madan, Falconer. The Early Oxford Press: A Bibliography of Printing and Publishing at Oxford ‘1468’-1640. (Oxford: Clarendon Press, 1895).
Digitized copies on Hathi Trust:
[rare leaves in the digitized Princeton copy (148) http://babel.hathitrust.org/cgi/pt?id=njp.32101035038189;view=1up;seq=411%5D