Lateral Weight

Lateral Weight is the quality formally defined in Theories of Lateral Weight as mass that accumulates perpendicular to a floor's primary catalogical axis. It is measured in selvage (Sv), a unit whose standard was fixed only after the revision of Annex A, Seventh Amendment, and it is the sole quantity the Tower recognises as capable of being wrong in more than one direction at once. Materials manifesting primary Lateral Weight are held and classified under the Lateral Stacks system, while pronounced and persistent cases fall to the jurisdiction of the West Lateral Stacks.

Definition and measurement

The prevailing definition descends from the work of Aethelred of the Unseen Corners, who first proposed a unified weight system to reconcile discrepancies between survey parties working the same corridor in opposite directions. Aethelred's original formulation held that Lateral Weight was a property of the object; the modern position, ratified in the Former Principles of Lateral Gravity and its successor theories, holds that it is a property of the object's relation to the floor, which is why two clerks weighing the same volume from different ends of a stack may both be correct and neither reconcilable.

Measurement proceeds by Annex A protocols: a specimen is placed on a Desk of Lateral Correspondence, allowed to settle for no fewer than four hours, and read against a reference chain whose calibration is renewed each chronological quarter. Readings below 0.3 Sv are not recorded, as the Lateral Cataloguing Guild maintains that such quantities fall within the ordinary noise of shelving. Readings above 41 Sv require a second clerk to witness the entry. Clerks are reminded that the reference chain is not to be used to open windows.

The Guild and classification

The Lateral Cataloguing Guild is the primary custodian and classification authority for materials and phenomena exhibiting Lateral Weight. Its classification is not one of degrees but of behaviours: a text that leans, a text that leans only when unobserved, and a text whose leaning is deferred to a later floor. The third category has caused the most difficulty. In the winter of floor 2,914, a consignment of ledgers classified as deferred-leaning was found on arrival to have discharged its entire lateral accumulation onto the receiving shelf, which subsequently registered 17 Sv and had to be reclassified as a holding in its own right.

The Lateral Stacks accommodate the first two behaviours by bracing and by spacing respectively. The West Lateral Stacks accommodate the rest, and are avoided by porters after the third hour.

Disputes and the Quiet Weight

Where two offices disagree on a measurement, the matter is not appealed but administered. Ceremony of the Quiet Weight is the formal adjudicatory rite of the Quiet Council, conducted on Quiet Floors with Mindfelt Padding placed to counterbalance whatever the parties have manifested between them. The ceremony is not a trial; no finding is issued. The Council instead declares the discrepancy quiet, after which the disputed reading is entered in the record without qualification and may not be raised again.

This has produced a body of settled absurdity. Categoryii Nonsequential Lateral Annex preserves some nine hundred such readings, among them a 1289 SCE entry recording a single folio simultaneously at 2 Sv and 19 Sv, both entries marked quiet, both cited in subsequent proceedings by parties seeking opposite conclusions.

Doctrinal disagreement

The Tetra-Lateral Accord was thought to have closed the question of whether Lateral Weight is conserved. Its Seventh Clarification formally supplanted the Former Principles and established that lateral weight may be transferred but not destroyed. The Ninth Concordance asserts the opposite in a single clause, and the Eleventh asserts both positions in consecutive sentences, the second beginning "notwithstanding the foregoing." The Lateral Cataloguing Guild has declined to adjudicate, noting in its annual return that the dispute is properly a matter for the Quiet Council and the Quiet Council has been unable to convene on the subject since its chamber was found to be leaning.

"Where two weights obtain and neither yields, the clerk shall record both and proceed. The record does not prefer the tidy account."

— Tetra-Lateral Accord, Annex 4, clause 12

Notable incidents

The Lateral Shift of Y156 SCE remains the largest recorded displacement. Some 4,300 petitions, stored flat for eleven years, shifted laterally in the course of a single night and were subsequently located in the Thirteenth Stairwell, stacked against the eastern wall at an average of 22 Sv. The Guild of Lateral Navigators was summoned to survey the stairwell and returned a report of four pages, three of which were the survey itself and one of which was a request that the stairwell not be surveyed again.

Smaller incidents are routine. The Desk of Lateral Correspondence on floor 1,606 has been reclassified as a specimen twice in living memory, and the Guild's standing guidance is that a desk which registers above 5 Sv should be reported rather than used. Clerks assigned to that floor are issued a second desk.

See also

• Tetra-Lateral Accord
• Annex A
• Ceremony of the Quiet Weight
• West Lateral Stacks
• The Aethelred Tome-Weight
• Lateral Feature Airspace