Pulmonary Brine Pools

The Pulmonary Brine Pools are a distinct geological and biological formation found primarily within the Salt Flats of Floor 44, characterized by their rhythmic expansion and contraction, saline composition, and role in the hypothesized respiratory cycle of the floor itself. Classified under Annex Δ-7 of the Second Concordance as "Ambient Peristaltic Features," the pools are a subject of considerable study by the Department of Ambient Physiology.

Physical Characteristics

Individual pools range from 3 to 15 meters in diameter and are filled with a dense, oxygenated brine of variable mineral content, echoing the shifting chemistry of the surrounding Flats. The defining characteristic is a regular, slow pulsation: a pool will expand over a period of approximately 72 hours, its brim creeping outward by up to half a meter, before contracting over a subsequent 48-hour period. This cycle produces a soft, susurrating sound audible within a 10-meter radius and creates concentric rings of precipitated salts along the pool's margins, which serve as a primary method for dating a pool's activity. The brine maintains a constant temperature of 17°C, irrespective of ambient conditions on the floor.

Proposed Physiological Function

The predominant theory, as outlined in the Treatise on Floor-scale Metabolics, posits that the Pulmonary Brine Pools function as gaseous exchange surfaces for Floor 44. According to this model, the contraction phase draws in atmospheric particulates and trace gases from the floor's atmosphere, which are dissolved and processed within the brine. The subsequent expansion is theorized to release a refined mixture of gases, primarily nitrogen and argon with trace noble elements, back into the environment. This process is informally termed "floor respiration," though the Third Concordance, Clause 809, explicitly forbids the attribution of animalistic functions to architectural structures, creating a persistent point of doctrinal tension.

Biota and the Brine-Skimming Tradition

The pools support a unique ecosystem of extremophile organisms, most notably the Ciliated Salt-Filterer, a translucent, worm-like creature that thrives in the hyper-saline environment. During the peak of the contraction phase, a viscous, nutrient-rich foam often collects on the pool surfaces. For centuries, a licensed guild known as the Foam-Skimmers of the Forty-Fourth has harvested this substance under strict quota governed by the Panel of Adjudication. The refined foam is a valued substrate in several archival preservation techniques and is listed as a Controlled Catalytic Substance in the Fifth Concordance, Annex B.

Scholarly Disputes and the Weeping Atlas Hypothesis

A significant minority of researchers, often from the School of Historical Geomorphology, contest the respiratory model. They argue the pools are merely residual effects, the still-pulsating remnants of a single, catastrophic event—often linked to the legendary Weeping Atlas said to have formed the Salt Flats. This school posits that the pulsations are a decaying harmonic resonance, not a active metabolic process, and that the pools are gradually, over millennia, slowing down and crystallizing solid. This view is supported by obscure measurements recorded in the Ledger of Dwindling Cycles, though its methodology is frequently challenged by the Department of Ambient Physiology.

Administrative Status and Access

Access to the primary cluster of Pulmonary Brine Pools, designated Zone Θ, requires a Class-C Ambient Phenomena Permit and accompaniment by a certified Archivist from the Department. Disturbance of the pool margins, sampling of brine below 2 liters, or interference with the Foam-Skimmers during active harvest is a breach of the Second Concordance, Clause 442, punishable by re-assignment to Dust-Verification Duty on a lower floor. The pools are monitored quarterly, with pulsation rates and brine composition logged in the Voluminous Register of Vital Fluctuations.