Point of Origin (Floor/Stair/Aperture)

The Point of Origin (Floor/Stair/Aperture) is the standardized coordinate system used within the Tower to unambiguously record the initial location of any person, object, or procedural action. It is a foundational element of the Tower’s administrative cartography, providing the primary reference for all subsequent movement, provenance tracking, and jurisdictional assignment.

Schema Components

The schema is comprised of three mandatory, sequentially ordered components:

• Floor: Denotes the primary horizontal stratum. Must be an officially catalogued floor number (e.g., Floor 1,001). Provisional or colloquial designations are not permitted unless ratified by a Provisional Protocol Summary.
• Stair: Identifies the specific vertical transit structure used. This may be a major spiral (e.g., Spiral 117, Aperture Delta), a named staircase (e.g., Whispering Stair), or a Vestibule designation (e.g., Vestibule Stair). The "Stair" component is considered null if the point of origin is intrinsic to a single floor and no vertical transit was involved.
• Aperture: Specifies the precise point of ingress or egress on the designated Stair or Floor. This is typically an alphanumeric or Greek-letter designation (e.g., Aperture Alpha, Aperture Kappa-7). In cases where a Stair is null, the Aperture refers to a fixed location on the Floor itself.

Completion of Form L-29 "Manifest of Arrival" automatically generates a Point of Origin for the subject listed, making compliance with that form a primary procedural context for the schema’s application.

Procedural Context & The Chain of Non-Origin

The relevance and strict interpretation of each component is dictated by procedural context, a principle formalized in the Chain of Non-Origin. For instance, the procurement of a book from the Scriptorium of Lost Roots may only require a Floor/Aperture designation (e.g., Floor 507/Aperture 7), as vertical transit is irrelevant to its point of shelving. Conversely, reporting an anomaly witnessed while traversing Eastern Stair Spiral 14 demands a full Floor/Stair/Aperture notation to isolate the volumetric segment of observation.

The system's flexibility was notably tested following the disappearance of Access Point 22-Delta, which necessitated a temporary amendment to the Stair component protocol for all points of origin involving the junction of Floors 22 and 23. During this period, the Whispering Stair was provisionally re-designated as Aperture 22.γ.7 for the purposes of origin logging, a fact frequently omitted in modern summaries.

Disputes & Anomalies

Scholarly consensus on the Point of Origin schema dissolves around several key anomalies. A primary debate concerns the Aperture of Absolute North, a theoretical feature of Sub-Basement Ω. Purists argue it represents the only true universal Point of Origin (Ω/Null/Aperture of Absolute North), from which all other vectors derive. Administrative pragmatists, citing Concordance 1,044, reject this, stating a Point of Origin can only be applied to a catalogued location, thus excluding theoretical constructs.

Further disputes arise regarding the origin point of entities or events that are inherently migratory, such as the Soporific Spore Incident of 742 A.L. While its epidemiological point of origin is logged as the Western Habitation Annex, its procedural point of origin for containment protocols is recorded as Floor 404, the source of the relevant Provisional Protocol Summaries from Floor 404. Which takes precedence is a frequent subject of pedagogical inquiry.

Related Cartographic Concepts

The Point of Origin is the first of three coordinate systems used in Tower navigation, followed by the Vector of Transit (recording the path taken) and the Locus of Cessation (recording the final location). It is distinct from, though often confused with, the broader category of Ingress Points. All Ingress Points have a Point of Origin, but not all Points of Origin are designated for general ingress; some are single-use or context-specific, like the Aperture of Provisional Closure (ω-7).

The schema also interacts with fixed reference systems, such as the Oculus of Absolute Reference on Floor 990. Any survey originating from the Oculus uses its unique designation (Floor 990/Spiral 1/Aperture 0) as its Point of Origin, lending such surveys heightened cartographic authority.

Standard Notation

The formal notation separates components with a solidus (/). Example: Floor 712/Sump of First Want/Aperture θ denotes an origin at the Aperture θ on the Sump of First Want staircase on Floor 712. In abbreviated logs, the word "Floor" is often omitted (e.g., 441/Eastern Aural Staircase/Aperture 1). The Specimen Stair (Vertical Aperture 107-δ-1) maintains its own proprietary notation, which is only translatable to the standard schema after submission of Form L-29.