Oneiric Cross-Contamination

Oneiric Cross-Contamination is the transfer of oneiric content — dream-stuff, sleep-state, or the residual coherence of a sleeping mind — between holdings that were not intended to share it. It is the principal concern of the Dream Registry and the only contamination class for which the Tower maintains a standing one-hour reporting rule. Where Conceptual Contamination concerns meaning and Perceptual Contamination concerns the senses, Oneiric Cross-Contamination concerns what happens when one floor's dreams begin arriving, uninvited and fully furnished, in the sleeping quarters of another.

Definition and scope

The Third Concordance, Clause 22, defines the offence as "the passage of oneiric material across a boundary not established for that passage, whether by canal, by index, or by the simple proximity of two holdings that should have been shelved apart." The definition is deliberately broad. Early recensions of the clause named only the Dream Canals; the revision of 11 March, following the second incident on Floor 1117, added the catch-all phrase "or by any means not yet enumerated," which has since been cited in every contested case.

Oneiric contamination is distinguished from Oneiric Feedback in that feedback returns to its own source, whereas cross-contamination necessarily involves two holdings. The distinction is maintained by the Registry at considerable expense and is not universally accepted; see Dispute below.

The Dream Canals and the one-hour rule

The Dream Canals — a network of slow-moving channels through which the Tower's oneiric content is understood to circulate — are the commonest vector. Oneiric Taxonomies classify the content that travels them, and a misapplied classification may send a category of dream into a holding listed for something else entirely. The Registry's standing instruction is unambiguous: emergency intervention for oneiric backflow or cross-contamination events in the Dream Canals must be reported within one waking hour.

Difficulty arises because the waking hour is measured from the moment of waking, and the Registry has never established whose waking is meant. The point was raised by Clerk Anneta Voss of the Registry's intake desk in the winter of the year the canals froze at the fourth lock, who logged a report and then, on the following day, logged the same report again, having slept in between and lost confidence in her reckoning. Voss's double filing is preserved as an example of correct practice.

Catalogue practice

Prevention follows the general doctrine set out in Cross-Contamination: holdings are isolated, measured, and kept apart by apparatus rather than by care. Mimetic Resonance Lamps are deployed in fields of Phantasmal Flora to hold oneiric content at a distance, and the Forty-Seventh Concordance extends this logic to the handling of Xanthoria catalogica, which has never been shown to dream but is kept separate anyway on grounds that have not been restated since the Forty-Seventh's first recension.

Annex Zeta provides the procedure where a contaminated holding is contaminated with something that does not exist, a condition classified under Paradox Contamination Type VII-C. The Antechamber of Unverified Antecedents on Floor 1117 is pressurized for precisely this reason. Night staff are reminded that the antechamber's inner door is to be left on the latch. The Office of Catalogic Logistics publishes the harvest calendar and asks that no one sleep on the stairs during it.

Notable incidents

The Leak of '88, which originated in the Cross-Indexing Annex and reached seven non-adjacent floors, was classified by the Registry as a mixed event: partly Conceptual Contamination and partly oneiric, since three of the affected floors reported dream material belonging to the other four. The Registry's final note observes that "the sleepers were on floors that had no sleepers" (Registry docket 88/Δ, fol. 6). The event is the reason Oneiric Integrity Screening was extended from Class-3 holdings to the whole of the eastern spiral.

A lesser incident, sometimes called the Winter of the Shared Stair, is recorded at Floor 1117 in the same period and involved a Class-3 Oneiric Artefact that was found to be dreaming in the manner of its nearest neighbour rather than its own. The artefact was re-shelved under Retroactive Contamination procedure and its neighbour was moved two floors away, where it is reported to have slept normally.

Dispute and authority

The Register of Thresholds, a subordinate recension never formally repealed, holds at Article 9 that "a dream that crosses a boundary is by that crossing a new dream, and belongs to neither holding." The Dream Registry rejects this position, citing Clause 22 and the practical observation that a new dream still requires a bed. The Provisional Tribunal on Ideological Contamination declined to hear the matter, noting in its minute of refusal that the question was oneiric and not ideological "and that the Tribunal has quite enough to do."

Where the two Concordances conflict — the Third Concordance asserting a single origin for any cross-contaminant, the Forty-Seventh Concordance permitting divided custody where the material settles unevenly — the Registry's practice is to file under both and report to the Echo Archive for a cross-reference ruling. The Echo Archive has not ruled since the eleventh filing. The Registry continues to file.

"Where a dream is found on a floor that is not its own, the finder shall not awake it, nor shall they return it, but shall record it and notify the Registry within one waking hour."

— Third Concordance, Clause 22, as revised

See also

Oneiric Taxonomies Oneiric Feedback Atlas of Oneiric Water Tables Class-3 Oneiric Artefact Type 5 Triggers of Contamination