One of the great pleasures of working here at Powell's is stashing an interesting or beautiful book at my desk for a few days. Did I say "stash"? I meant "study."
I've been paging through the delightful limited edition quarto A Study of Rare Books by Nolie Mumey. It contains reproductions of title pages, press devices, and colophons of great editions ? the Gutenberg Bible, the 1611 King James Bible, Boswell's Life of Samuel Johnson, etc. ? printed on lovely paper with generous margins.
One of the other fabulous things about working here is learning something new every day. In the section on collation, Dr. Mumey writes:
To recognize the size of a book, hold the page to the light to show the fine lines, called "wire mark," which are placed about an inch apart running parallel to each other. In octavos, folios, 12mos, 32mos, they are perpendicular; in quartos, and 16mos, they are horizontal.
Makes sense! I just hadn't thought of identifying the format by looking at the wire marks, or "chain marks."
In days long gone by, when books were actually printed with moveable type, the text was printed and then the paper was folded into signatures. The size of the folded sheets dictates the size of the book, or format.
When reading a rare book description, the format should be part of the notation. The most common is octavo, abbreviated as 8vo. Folio is usually written out, but can be listed as Fo. Here's a list of the abbreviations, in order of descending size:
Folio : Fo
Quarto : 4to
Octavo : 8vo.
Duodecimo : 12mo.
Sextodecimo : 16mo.
Tricesimo-secundo : 32mo.
I gathered a few of these together for a group photo. The largest is the folio, the square book with marbled boards at the top is the quarto, the red book below that is the octavo, and the smallest in the photo is a duodecimo.
When does this matter? An atlas or book of engravings wouldn't be very appetizing printed as a 24mo. A book of devotions or daily meditations would be hard to take to church printed as a folio. The size should fit the book's purpose.
There is so much paper in our lives now that it's hard to think of it as a costly commodity. Hundreds of years ago it was precious, and the price of a book reflected the quantity and quality of the paper used in its production. Here are photos of an example; this is the same title, printed with the same plates, but in different sizes from different printers.
The larger of the two was printed by John Murray. The smaller, beautifully rebound in modern full calf, hasn't the magnificence of the full margins. Printed by Thomas M'Lean, it has no date on the title page, but has been dated by the watermarks.
They are different sizes, obviously, but they are both quartos, and are identified as such in their descriptions.
Confused? Don't be. Take a deep breath, read the description of format in your copy of Carter's ABC and preorder your copy of the new Harry Potter which, I'm betting, will be released in 8vo. format.