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The Collation

Fun in cataloging, or, the mysterious 12mo

On occasion, interesting and unusual aspects of books, manuscripts, and prints catch the attention of the cataloger at work on them. 1 The office of the Cataloging and Metadata Department (located on Deck A right below the Paster Reading Room) is an open area with a large table in the center, which makes it really easy to show each other the cool stuff we come across. Something interesting, unusual, and cool crossed my desk recently, and it seems a shame not to share it with a wider community.

title page of John Newton's Tabulae mathematicae

title page of John Newton’s Tabulae mathematicae

John Newton’s Tabulae Mathematicae, or, Tables of the Naturall Sines, Tangents and Secants, published in 1654, offers up exactly what the title promises: hundreds and hundreds of pages of dense numbers in tabular form. Tucked in among its 452 unnumbered pages is a folded leaf containing (wait for it … ) a table. So far, nothing unusual.

Now we’re getting to the fun part. When the folded leaf is unfolded, we see a lot of wasted space, in stark contrast to the compact printing everywhere else. 

  1. One such item was written up by Sarah Werner last December in “‘Tis the season for almanacs.”
  2. For more on signature marks, see Sarah’s “Deciphering signature marks“.


Nifty! This kind of plate is known as a “throwout” plate, and is nicely described by Roger Gaskell in “Printing house and Engraving Shop,” _The Book Collector_, vol. 53, no. 2 (Summer 2004), page 213-251. He writes, “The familiar problem of reading the text of a book while referring to an illustration was commonly solved in the seventeenth and eighteenth centuries by binding the plates as throwouts. Throwout plates are attached to the book in such a way that they can be opened out with the image thrown clear of the text block, so that any page can be read while looking at the illustration.”

Sometimes throwouts were planned by the printer/publisher, like this example. In other cases, they’re copy-specific: the binder would add a blank leaf, then paste the plate face-down along the fore-edge.

Erin Blake — June 17, 2014


What are the conjugacies? In other words, how does the imposition of Q differ from the Gaskell diagrams? Are Q1 and 2 singletons, or might the foldout table have been printed as Q11-12 and remained attached to either Q1 or Q2, with the sewing after Q6 as in a normal gathering of 12? (Is there anything on the reverse of the foldout table, or is it blank?)

John Lancaster — June 17, 2014


That’s a good question. Deborah is out of town, but I’ll pop down into the Reading Room as soon as I have a chance and see what I can find out.

Sarah Werner — June 18, 2014


I think John is correct, but I think we can be more precise. Using Gaskell’s imposition scheme for common 12s (fig. 55), if the cut is made towards the inner margin of Q11 then the foldout is comprised of Q12r.Q11v. This would leave the conjugate of Q11, that is Q2, unsupported if the cut were made in the gutter. Hence the position of the black line which is brought in from the margin to leave a stub for Q2. The cut has to be made before folding. The notes to the formula should therefore read ‘The folded table was imposed on Q12r.Q11v (the full point here indicating conjugacy in the unopened bolt)’.

Roger Gaskell — November 21, 2019


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