Annex Delta of the Seventh Concordance

Annex Delta of the Seventh Concordance is the operative annex to the Seventh Concordance, ratified in the eleventh year of the current recension and amended, by the Librarians' own tally, forty-one times since. It is the instrument by which the Seventh Concordance is actually administered: where the parent document sets out principles, Annex Delta sets out floors, forms, and seals. It is best known for having retired the Beta-4 Designation Framework, for establishing the Botanical Register, and for containing at Clause 19 the Priority-by-Obscurity Model by which nearly all requests to the Tower's reading rooms are now ordered.

The Annex is not one text but a sleeve of them. Clerks speak of "Delta" to mean whichever recension is nearest to hand, a habit the Office of Recensions has twice attempted to correct and twice abandoned.

Structure and contents

Annex Delta runs to nine clauses, of which four are routinely cited and five are routinely mislaid. Clause 17 governs the Argent Vaults and their disputed contents; Clause 19 formalizes the Priority-by-Obscurity Model; Clause 22 establishes the Botanical Register and the scope of the Botanical Registry that succeeded it; and Clause 33, added at Revision 4, authorized the ratification of the later Seventh Concordance Annex D Clause 22, a document whose relationship to its own namesake is the subject of a standing disagreement described below.

Annex Delta-7, a schedule appended to the Annex, describes Aspinal Referencing, the calculation by which a petitioner's proximity to the Central Spiral is expressed as a fraction. The schedule gives worked examples for floors 12, 406, and an unnamed floor which the examples refer to only as "the one with the wet stair."

The Annex also contains the standard protocol for a Materialization Watch, a procedure requiring two clerks, one lantern, and a witness who has not previously been on the floor in question. The protocol is not permitted to be read aloud.

Ratification and the Clause 33 question

Revision 4 of the Annex was ratified under Clause 33 of Third Concordance, Clause 33, Annex Delta, an instrument drafted for an unrelated purpose and reused, in the words of the ratifying minute, "for want of a better hook." The Office of Recensions has never resolved whether this makes Revision 4 valid or merely tolerated. The distinction has practical consequences: a tolerated annex cannot compel a floor to appear, whereas a valid one can.

Seventh Concordance, Revision 4 is therefore cited in two incompatible ways. Clerks of the old school cite it as authority; clerks of the new cite it as precedent for citing things that are not authority. Both citations are accepted at the desk and neither is explained to petitioners.

The Beta-4 retirement

Annex Delta's most consequential act was the formal retirement of the Beta-4 Designation Framework, which had until then governed the naming of floors whose names had been lost. Beta-4 permitted a floor to be designated by the sound it made when walked upon. The practice produced designations such as Beta-4/Thud and Beta-4/Thud-With-Squeak, and eventually two floors with identical designations four hundred storeys apart.

The retirement took effect immediately and retroactively, a formula the Office of Recensions defends on the ground that "immediately" and "retroactively" were entered by different clerks and neither would withdraw. Floors designated under Beta-4 retain their designations but may not answer to them.

Annotations and the Theta note

A marginal annotation attributed to Clerk Theta was discovered in the Annex's working copy in the archive's 214th year and has since been reproduced in every subsequent impression. It concerns the nature of vacancy, and reads in part:

"A vacant floor is not an empty one. It is a floor which has declined to be counted, and the count proceeds around it. Do not enter a vacancy to verify it; the verification is what makes it a room."

— Clerk Theta, annotation to Annex Delta, Clause 9

Clause 9 makes no mention of vacancy. The Office of Recensions has ruled twice that the annotation has no force and twice that it has, and the two rulings are filed in the same folder.

Disputes and administration

The chief standing dispute concerns which document Clause 22 establishes. Annex Delta's Clause 22 establishes the Botanical Register; the later instrument known as Seventh Concordance Annex D Clause 22 is styled as though it were that same clause reissued, and the Botanical Registry has since been administered under both. The Hepatic Delta collection is catalogued in the Register and indexed in the Registry, and appears in neither twice.

Administration of the Annex falls to the Substrate Quarries Works, whose perpetual charter under Annex Delta obliges it to supply the stone for any amendment's seal. The Works has complained, in a letter of the 301st year, that it is asked to supply a new seal for every amendment while the amendments are never read, and that it has begun casting seals in advance. The complaint was acknowledged and the practice regularized.

The Annex is consulted in the reading room on floors 9 and 88 and in the annexe adjoining Delta-44, which holds the only complete set. Petitioners are asked to return the sleeve to the shelf themselves, as the shelf has been known to move. Errata are collected each winter and bound into the following year's impression, where they are corrected.