Often, I learn the most about the behind-the-scenes story of a book when somebody messes up. Statuti ciuili, et criminali dell’isola di Corsica is the first book printed on the island of Corsica, and it shows; the paper is terrible and the typography is a bit sloppy. The book ends with a very lengthy list of errata (see above comment about the typography) printed on a single leaf, and in a normal copy of the book, that’s all I’d know about it. My copy, however, contains 2 copies of the same errata leaf at the end. Because the binding is as crummy as the paper, I can see into the gutter margin to the sewing, which makes it clear that both copies of the errata leaf were printed on the same sheet of paper. Since this book is a folio, each leaf in it occupies half a sheet of paper, so the printer did the smart thing and set the type of the errata leaf twice. Thus, instead of printing a single leaf (say) 200 times, he only had to print 100 2-leaf sheets. Of course, the crucial step to making this trick work is that you have to remember to separate the leaves, and put each one in a different copy. It’s no earth-shattering discovery; printers did this sort of thing all the time. It’s just that when they do it right, it’s likely to go unnoticed, and this way we know a little more about the making of this book.