Foliation — Historiation
Folio: A book format, commonly abbreviated 2º. The folio is the largest format, consisting of a piece of paper that has been folded once to produce a gathering of two leaves (or four pages). Folios are also the only kind of format that does not require any cutting. The term can also refer to a leaf, regardless of the book’s format (see foliation for more).
Font: A complete set of type in a given design (called a “typeface”) and size, i.e., 12-point Garamond or 14-point Caslon. Pieces of type that all represent the same letter are called “sorts.” A font might contain different numbers of different sorts, which were provided proportional to their use. Since they are made of metal, fonts are quite heavy: a font of roman type might weigh 243 kilograms (or about 536 pounds).
Format: Properly, the relationship between the printed page and the sheet of paper on which it was printed. Paper was delivered to the printer in sheets, which were printed with a certain number of pages. The sheets of paper were then folded and/or cut to produce gatherings of different numbers of leaves. Formats are numbered based on how many leaves they contain; counterintuitively, the larger the number of leaves in a book, the small the resulting format will be. The most common formats are the folio (2º), the quarto (4º), and the octavo (8º), but smaller formats were possible as printers could keep folding their paper. Formats smaller than octavo are comparatively rare and are usually just referred to with a number and the syllable “mo”; the most commonly named ones are 12mo, 16mo, 24mo, 32mo, 64mo, and 128mo. A 128mo book requires seven folds and produces 128 leaves out of a single sheet of paper: producing one is not for the faint of heart.
Foxing: A general term for the discoloration or staining of paper, typically with brownish-yellow spots. Several different effects can cause foxing, ranging from the paper’s chemical makeup to microorganisms living on it, but it is generally accelerated by humidity or lack of proper ventilation. Foxing does not destroy paper, but it does make it less attractive.
Gathering: A set of folded pages ready for binding. A gathering may consist of multiple sheets of paper (e.g., three sheets that have been folded once to form folios and nested within one another) or just one sheet that has been folded multiple times. Printed gatherings commonly have signature marks and are therefore sometimes called “signatures,” but gathering is a more precise term.
Gloss: An annotation in the margins of a book intended to explain or clarify the main text. Sometimes glosses are also “interlinear,” i.e., written between the lines. Medieval scholars were particularly fond of glosses and it is not uncommon for a page to be more gloss than text in a medieval or early modern edition. In these less heavily glossed times, readers must make do with footnotes or endnotes.
Half bound: A binding style where the spine, part of the boards, and the corners are bound in one material while the rest of the cover is bound in another material (or left unbound).
Headband: A band at the head and/or tail (i.e., the top or bottom edge) of the spine of a book. Headbands can be sewn (in which case they serve to reinforce the spine) or merely pasted on (in which case they just look nice). Islamic bindings are known for their distinctive chevron-shaped headbands.
Historiation: The decoration of initials with images of people or animals rather than the more usual plants or floral designs.