The Annex 4 Schematics

Scope and identification

The Annex 4 Schematics are the primary visual and technical reference for all certified substructures, appendages, and non-sequential expansions within the Tower. They are held under governance of the Third Concordance, Clause 112, Annex Δ, and are maintained as a composite document comprising folded plates, elevations, and stippled section drawings at a nominal scale of 1:200, though the scale is stated differently on Plates 9 through 14.

The Schematics are frequently confused with their several partial copies and derivative recensions. The designation refers specifically to the operative composite held at Annex 4, not to the verification copies distributed to the regional Bureaus of Structural Integrity, nor to the earlier folio now catalogued as Annex IV.

Physical description

The working set consists of 312 plates bound in four volumes of buff vellum, with a fifteenth supplementary gathering sewn in annually during the Survey Window. Plate dimensions are uniform at 610 × 470 mm, with the exception of Plate 207, which is 610 × 470 mm when closed.

Notations appear in three hands: a formal drafting hand consistent with the Scriptorum of Vertical Surveys, a cramped marginal hand identified as belonging to Clerk-Verifier Haddad, and a third hand that appears only on plates concerning the region below Floor 7,401 and has not been attributed. Annotations in the third hand are invariably correct.

Governance and disputes

Administration of the Schematics is contested between the Department of Structural Integrity and the Department of Structural Verifications. The dispute, first formally lodged in the winter of the Long Recension, concerns which department holds drawing authority over appendages that were constructed before the relevant clause existed. Both departments cite Third Concordance, Clause 112, Annex Δ; the Clause does not resolve the matter, having been amended eleven times since the dispute began.

Under the Second Concordance, Fig. 1 is formally classified under Annex 4: Structural Schematics — a classification that has no equivalent in the Third and is therefore treated as precedent by one department and as obsolete by the other.

The Cartographer-Scribes may apply for permits to update the annex's structural schematics during the Survey Window. Applications submitted outside the Window are returned unopened with a slip reading "not concurrent." The Window runs from the first thaw to the last, and in two recorded years has not occurred at all.

Historical incidents

The most consequential error in the Schematics' history is the omission of Annex 12c from Plates 44 through 51 for a period of forty-one years. Annex 12c, which is housed within the primary structural envelope of Annex 4 itself, was drawn only in dotted outline after Clerk-Verifier Haddad noticed that the load calculations on Plate 47 accounted for mass that appeared nowhere in the elevation. The dotted outline remains to this day, though the annex has since been fully surveyed.

In the winter of the Scriptorum Fire, Plates 288 through 296 were lost to smoke. They were replaced from memory by Archivist-Lieutenant M. Kael, whose replacements were ruled "substantively identical" by the Department of Structural Verifications and "unacceptable in every particular" by the Department of Structural Integrity. Both rulings are on file.

Scholarly disagreement

The Tower's principal unresolved question regarding the Schematics is whether they describe the Tower or prescribe it. The Department of Structural Integrity holds that the drawings record what exists and that errors are drafting failures to be corrected. The Department of Structural Verifications holds that the drawings define what is certified to exist and that discrepancies in the built fabric are construction faults to be corrected. Under the first reading, the Schematics are amended to match the Tower; under the second, the Tower is amended to match the Schematics.

A minority position, associated with the Intent Certified Architects, holds that the distinction is a category error of the kind already dismissed in matters of un-rooms and pressure differentials, and that the Schematics describe neither the Tower nor its certification but a third thing for which no term has been agreed.

The Vestigial Endorsement appearing on the flyleaf of Volume I — a seal of an office abolished before the current recension — has been cited by all three parties as supporting evidence. No party has explained how.

Custody and access

The Schematics are stored at Annex 4 under glass, with two plates on permanent display: Plate 1, the general section, and Plate 207. Consultation requires a chit from the Pre-Review Documentation desk. Chits issued before noon are honored; chits issued after noon are honored only if the clerk who issued them is still on duty, which is a matter of record rather than policy.

Verification copies are distributed to regional Bureaus of Structural Integrity on a five-year cycle. The cycle has not been completed since the third distribution.