A Quick Guide to Arcane "Desbib" Vocabulary and Format Detection
"Edition": All books printed from a single setting of type.
"Impression": all copies of an edition printed at any one time | "Issue": all copies of an edition packaged for sale by a book seller |
"State": Differences in individual copies of the same edition/issue caused by deliberate corrective changes in the way any page's type was set during printing, or by wear and tear on individual pieces of type or engravings or ornaments (e.g., printers' colophons).
Format Detection for the Four Most Common Formats in Early Books
Chain line orientation? Watermark location?
Vertical (folio or octavo) center & whole = folio (Fo)
divided upper gutter corner = octavo (8o)
Horizontal (quarto or duodecimo) in middle of gutter & half = quarto (4o)
1/3 from top/bottom outer edge = duodecimo (12mo)
When in doubt, go to the Canvas discussion forum for "Cadaver Book Descriptive Bibliography ("desbib") Notes" and print a copy of the Goucher watermark paper to use for the folding exercise. Always remember to rotate the sheet after each fold and before the next in a clockwise direction so that the folded edge remains on the top.
(Exceptions? In smaller formats, clever printers saved paper by printing by "half-sheet imposition," so that two identical sets of pages are set up on each half of the sheet, which is then cut in half before binding to make leaves for two different copies or even two different editions (!). See Williams and Abbott, and Philip Gaskell for examples.)