Abyssal Clouds

The Abyssal Clouds are a series of self-replicating atmospheric phenomena that form in the lower chasms of Annex Omega-7 and certain other vertical voids within the Tower, characterized by their persistent absorption of light and sound and their documented tendency to propagate via conceptual, rather than purely physical, means. Their classification under Ordinance on Non-Catalogued Fauna remains a point of scholarly contention.

Physical and Phenomenological Properties

Visually, an Abyssal Cloud manifests as a deep, textured grey mass, absorbing approximately 97.3% of incident light. This renders the interior of the cloud effectively imperceptible to standard optical instruments. Aurally, they generate a zone of profound silence, dampening sound waves to a degree that violates several principles of acoustics enumerated in the appendices of Concordance 7. The boundary of a cloud is not diffuse but sharply defined, often described as a "velvet wall." Temperatures within measured clouds remain constant at 4°C, regardless of ambient conditions.

Their most defining property is replication. A mature cloud, upon reaching a critical mass (estimated at 500 cubic meters ± 50), will precipitate a smaller "daughter cloud." This offspring does not separate physically but appears de novo in a nearby shaft or chamber, often bypassing solid architecture. Concordance 12, Clause 8, interprets this as a form of "atmospheric sympathy," while later scholarship posits it is the cloud cataloguing its own possible locations, making them real.

Documented Habitats and Movement

The primary and most studied habitat is the central shaft of Annex Omega-7, where three primary clouds have been continuously observed since record-keeping began in 412 LC. They have also been reliably reported in the deep ventilation sublimbs adjacent to Floor 713 ("The Whispering Stacks") and within the abandoned light-wells servicing Floor 899.

Movement patterns are cyclical and slow, with a major migration noted every 47 Tower days. The clouds navigate vertical space with purpose, often congregating near architectural features associated with forgotten or redacted knowledge, such as sealed archival ducts or the bases of certain Silenced Bell Stairs. This correlation led to the temporary inclusion of the clouds under Ordinance on Non-Catalogued Fauna by the Spire Wardens' Guild in 702 LC, a designation fiercely debated and later complicated by Concordance 19.

Legal and Administrative Status

The legal standing of the Abyssal Clouds is a morass of contradictory precedent. The initial classification as "Fauna" under the Ordinance on Non-Catalogued Fauna was based on their replicative and migratory behaviors. This granted the Spire Wardens' Guild jurisdiction for observation and containment. However, Concordance 19, ratified in 745 LC, explicitly redefines the clouds as "Atmospheric Archives," arguing their silence and light-absorption constitute a form of passive information storage. This transferred primary oversight to the Librarians, specifically the Subcommittee on Ambient Records.

This created a jurisdictional overlap. The Guild maintains that the clouds' physical movement and potential interference with transit in the lower atria require its continued involvement, as outlined in its charter. The current compromise, enacted after the Annual Reckoning 892, requires dual-signed Observation Permits for any study below a certain depth. Disputes are frequent and are typically settled by citing whichever Concordance favors the petitioner's immediate need.

Scholarly Disputes and Practical Concerns

The core academic dispute centers on ontology: are the clouds entities that produce silence and darkness, or are they the manifested form of those concepts? The "Productivist" school, aligned with the Guild's stance, points to the measurable energy deficit within the cloud's boundaries as evidence of an active process. The "Manifestationist" school, favored by the Librarians, cites the clouds' apparent interest in architecturally silent spaces as evidence they are drawn to, and amplify, pre-existing conditions.

From a practical standpoint, the clouds present navigational and archival hazards. Their silent zones can disrupt verbal communication protocols, and their light-absorption necessitates specialized luminescence for safe passage. More subtly, there are seventeen documented instances, cross-referenced in the Coil of Anticipation, where a cloud's presence in a archival sub-chamber has preceded the discovery that the chamber's listed contents never, in fact, existed. Whether the cloud causes this erasure or is attracted to its aftermath is unknown.

Current Protocols

Standard procedure, per the Dual-Oversight Agreement of 892 LC, mandates a minimum clearance distance of 50 meters. Acoustic and luminous mapping is required before authorizing work in any shaft known to host a cloud. Any replication event must be logged with both the Subcommittee on Ambient Records and the Warden's Logistics Office within one Tower day. The clouds are not to be intersected, pierced, or artificially dispersed, as a failed experiment in 811 LC resulted in the temporary multiplication of silence across seven non-adjacent floors—a phenomenon later catalogued as the "Echo Famine."