Conjugate leaves have a rather clear definition, meaning one single piece of paper folded to form two leaves, or more familiarly, four pages (Carter). In An Introduction to Bibliography for Literary Students, Ronald B. McKerrow defines conjugate leaves a bit more complexly. He defines them as two leaves, which, “if traced into and out of the back of the book are found to form a single piece of paper” (27). Nonetheless, the use of conjugate leaves has been used for centuries, and can often be identified by a paper’s watermark. Watermarks, which date back to the seventeenth century, are designs left behind by a producer on a sheet of handmade paper from when that sheet is set, and can only be seen when held up to the light (Carter). Similarly, chain lines and wire lines can be used to identify format, and therefore conjugate leaves, in a bound book. These lines appear from the mould used in the process of making paper; they allow excess water to drain while maintaining stability (Carter). Figure 1 demonstrates a set of conjugate leaves from an eighteenth century book and the evidence of wire lines when held up to light.
At first glance, the leaves do not appear to be conjugate, but instead separate leaves, commonly called “singletons” (Carter). This is because older books, if not preserved properly, tend to fall apart when not bound well. We can, however, infer the conjugacy of the leaves by the continuation of chain lines through the middle of the sheet. In an article written by a Lennox Foundation Preservation Intern, Henry Herbert, a nineteenth century quarto manuscript is observed and rebound. In Figure 2, Herbert observes, “toward the front and the back of the book, many pages had been separated from their conjugate leaves, leaving a mass of single sheets.”
According to John Carter in ABC for Book Collectors, conjugate leaves are most often associated with pages not necessarily related to the text itself; blank pages, advertisements and preliminary pages, including the title and half-title pages, are usually printed on conjugate leaves (73-74). This is not to say conjugate leaves are not used throughout the book, however. Fredson Bowers describes the utmost importance of conjugate leaves in bookmaking in Principles of Bibliographical Description; “…format indicates structure: the number of page units to be printed on one side of a sheet determines the number of times the sheet must be folded, after both sides have been printed, to create a sequence of conjugate leaves… that can be sewn through the fold to the spine cords holding together all the folded sheets for a given book” (38). Therefore, conjugate leaves are significant to the study of books because by studying the sets of conjugate leaves in a given book, we can deduce the printing techniques used, the order in which pages were meant to be bound and, when examining format, how many times given sheets were originally printed and then folded. For example, in an octavo format, each gathering consists of four conjugate leaves after folding and cutting a larger sheet with eight printed pages on each side, resulting in eight leaves and sixteen pages. Information like this is crucial to determining the history of the book construction. By observing the way a book was made (by looking at the use of conjugate leaves among other techniques), we can deduce information about the time period in which it was constructed based on the history we already know. Thomas Tanselle discusses some of these techniques and how they are used to recreate the sequence of bookmaking events in The Treatment of Typesetting and Presswork in Bibliographical Description. “Some details in them may result from seemingly pure observation, such as the dimensions of a leaf, the direction of the chainlines relative to the leaf, or the conjugacy of certain leaves…” (3).
The use of conjugate leaves can also be used to determine the authenticity of a copy of a book, as in studying the replication of Robert K. Turner Jr.’s, A Description of Carolana, discussed in the 1957, Volume 9, edition of journal Studies in Bibliography. “This suspicion is made stronger by the fact that in one copy (ViU 291418) two stubs are found between the conjugate leaves I2 and I3.” In this book from the 1700s, the original printed sheets were found in a brand new binding that was being resold. Binding variation with the observation of conjugate leaves, in this case, can be studied to determine book authenticity.
When studying my personal book, This Book Will Save Your Life, by A.M. Holmes, I observe gatherings of conjugate leaves bound together to create a complete text. This technique aids in binding by ensuring security of the leaves- if the leaves were singletons they might not be as permanent in the final binding. This affects the actual reading of the book by making it more durable, and more resistant to damage from frequent page turning and stretching of the binding. Unfortunately because this is a modern book, there are no signatures on the pages. Without signatures it is difficult to tell the format of the book, and therefore the number of conjugate leaves in each gathering.
Bowers, Fredson, and G. Thomas Tanselle. Principles of Bibliographical Description. Winchester: St Paul’s Bibliographies, 1994. Print.
Carter, John, and Nicolas Barker. ABC for Book Collectors. New Castle, DE: Oak Knoll, 1995. Print.
Herbert, Henry. “Checking in with Former Lennox Foundation Interns: Henry Hebert.” Parks Library Preservation. Lennox Foundation, 26 Aug. 2011. Web. 11 Oct. 2014.
McKerrow, R. B. An Introduction to Bibliography for Literary Students. Oxford: At the Clarendon, 1927. Print.
Munby, A. N. L., and Fredson Bowers. “Studies in Bibliography. Vol. 9, 1957.” The Modern Language Review 53.2 (1958): 232. Web.
Tanselle, G. Thomas. “The Treatment of Typesetting and Presswork in Bibliographical Description.” Studies in Bibliography 52 (1999): 1-57. JSTOR. Web. 13 Oct. 2014.
Contributed by Kathryn Wiesendanger.