Vat-moss

Vat-moss designates any of six lichenized bryoid complexes exhibiting catalysed, substrate-specific growth patterns when exposed to effluvia from the Primary Humour Retention Vats. Its cultivation and containment are governed under Annex 7 of the Tenth Concordance, with supplemental protocols issued by the Humour Regulation Guild.

Primary Variants and Characteristics

Six distinct variants are catalogued, each corresponding to one of the three primary humours or their documented admixtures.

• Choleric Bind-Moss (Vat-moss Alpha): Exhibits a brittle, crystalline structure and a high affinity for metallic surfaces. It is the primary component in the sealing grout used along the Sub-basement Gamma Vat Perimeter. Its growth is accelerated by exposure to Choleric Residue.
• Sanguine Creep (Vat-moss Beta): A fast-growing, filamentous form with a distinctive crimson sheen. It displays thigmotropic behavior, often forming dense mats that can impede drainage grates in sub-basement sectors. Studied for its potential in filtration, though its tendency to clog valves remains a logistical challenge.
• Phlegmatic Bloom (Vat-moss Gamma): Characterized by its gelid, translucent pods that slowly release a neutralising mist. This variant is often found in condensation zones near Sub-basement Gamma and is considered non-hazardous, though its slippery residue presents a minor slip hazard.
• Melancholic Shroud (Vat-moss Delta): An admixture-responsive variant, appearing as a dark, velvety pellicle that absorbs ambient sound. Its relationship to Silent Moss is disputed, with some scholars arguing it is a humour-induced epiphyte of the latter.

Cultivation and Containment Protocols

Intentional cultivation of Vat-moss requires a Class-C Humour Handler’s licence and must be conducted in designated ateliers, most notably The Vat on Floor 440. Unauthorised propagation is a violation of Concordance 10.7.12. The standard cultivation procedure involves the application of diluted humour samples to a sterile pumice substrate, followed by a 72-hour incubation period under controlled luminance not exceeding 50 lumens.

Containment breaches, typically involving Sanguine Creep, are to be reported to the Humour Regulation Guild within one hour. Standard remediation involves application of a salt-petrol solution, as per Guild Ordinance 331. However, a minority opinion within the Inkmixing Guild contends that a tincture derived from Mourning Moss is more effective, leading to occasional jurisdictional disputes during cleanup operations.

Applications and Prohibited Uses

Vat-moss has several sanctioned industrial applications. Choleric Bind-Moss is milled into a powder for structural sealants. Phlegmatic Bloom extracts are used in certain humidity-regulating inks. The most significant development was Selena Moss’s pioneering work with Sanguine Creep filaments, which led to the development of Lumen-Moss Symbiotic Tincture.

Prohibited uses are extensively documented. Concordance 8.22.1 expressly forbids the use of any Vat-moss in foodstuffs or medicinal preparations. Furthermore, the attempted hybridization of Vat-moss with Sigh-Moss or Creeping Phosphor-Moss is a cardinal offence under the Guild Charter, due to the unpredictable and often violently expressive bio-luminescent events that result.

The Spirelocation Debate

A persistent scholarly controversy concerns the applicability of the Moss Growth Spirelocation methodology to Vat-moss colonies. The technique, developed for defining the boundaries of natural Moss-Growth Spires, relies on ambient spore precipitation. Proponents, led by the school of Kaelen Moss, argue that humour-catalysed growth follows analogous volumetric principles and that Spirelocation can predict containment failure points.

Opponents cite the Incident on Floor 331, where the misapplication of Spirelocation parameters to a Sanguine Creep outbreak resulted in a significant overestimation of its metabolic decay rate, exacerbating the breach. The debate remains unresolved, with the Humour Regulation Guild maintaining a default position that Vat-moss is an artificial construct and thus outside the scope of traditional bryological cartography.

Specimen Depositories

Live archival samples of all six primary variants are maintained in the Humour-Regulated Botanical Collection on Floor 112. Dried and inert specimens are held in the Central Herbarium on Floor 900. Access to live specimens requires dual authorization from the Humour Regulation Guild and the Office of the Chief Botanist. Notably, no Vat-moss has ever been successfully cultivated outside a 300-floor vertical radius of the Primary Humour Retention Vats, supporting the theory of a humour-dependent symbiotic lifecycle.