How to read a manuscript collation formula

A catalog description may include a line such as 1-12⁸ 13⁶(−6). A collation formula gives a compact account of the cataloger's interpretation of the manuscript's gatherings and recorded additions or losses. It is not a complete history of every structural change.

Notation varies among catalogs and scholarly traditions. The diagram accepts the grammar defined below; consult the catalog's key when reading another formula. The University of Nottingham's guide to forming quires and reading a collation gives a worked catalog example.

The grammar, one token at a time

A manuscript is sewn together from quires (also called gatherings): little booklets of folded sheets, stacked and stitched. A collation formula describes each quire in order:

• 1⁸: quire 1 has eight leaves. The superscript counts leaves, not pages: eight leaves, sixteen pages.
• 1-12⁸: quires 1 through 12 all have eight leaves. Runs of identical quires collapse into a range, which is why a 400-page book can fit in a short line.
• 13⁶(−6): in this tool's grammar, quire 13 is modeled as six leaves with leaf 6 absent. Establishing whether the leaf was lost, cancelled during production, or represented differently by the cataloger requires other evidence.
• 2⁷: an odd leaf count. It signals a structure that cannot consist only of intact bifolia, but the formula alone does not identify loss, cancellation, insertion, or repair.

Superscripts are typographic convention: plain ASCII 2^8-4 says the same thing as 2⁸(−4), and the tool below accepts both.

Why halves matter: conjoint leaves

One fact makes collation worth recording at all. A quire's leaves are not independent: they come in pairs, because each pair is one folded sheet, a bifolium. In an eight-leaf quire, leaf 1 and leaf 8 are two halves of the same piece of parchment, and so is each pair inward until 4 and 5 meet at the center. The pairs nest like brackets.

Leaves that share a sheet are conjoint. If one leaf is cut away, a stub may remain while the other leaf stays attached through the fold and sewing structure. Conjoint structure can help a cataloger test hypotheses about missing or inserted leaves, but it cannot identify a displaced leaf's former volume without independent evidence.

Read one for yourself

Type a formula, or start from an example. Click any leaf to see its conjoint partner. The link in your address bar updates as you type, so a diagram can be shared as easily as the formula itself.

In this tool, 1-4⁸ draws four eight-leaf gatherings. 1¹⁰(−1,−10) marks both leaves of the modeled outer bifolium as absent. The odd middle gathering in 1⁸ 2⁷ 3⁸ requires closer examination: it may contain a singleton, a cancelled leaf, a lost leaf, an insertion, a repair, or a structure that this compact notation does not express.