The Sump

The Sump is the designation, formalised under Third Concordance §212, for Floor 666 and its permanently stationed occupant, The Conduit. The word is never used in the plural in administrative writing; the Librarians hold that what descends into the Sump is a single continuous stream, however many channels deliver it, and that to speak of "sumps" is to invite the confusion that produced the Affair of the Twinned Gargoyles in the first place. Floor 666 is the lowest catalogued level to which an expedition has returned a floor-plan rather than an inventory.

Designation and early concordance

The number 666 was first entered in a survey roll of Year 41 by an unnamed clerk of the Stairwell Register, who recorded it in the sequence 664, 17, 666, 665 without comment. The Third Concordance, compiling the survey a decade later, adopted the entry without correction, noting only that the floor "is not to be renumbered, as renumbering has been found to unsettle it." Later recensions of the same Concordance, in Fifth Concordance Annex 3, describe the floor instead as "the interval beneath the last interval," and it is on this phrasing that the principal scholarly disagreement turns — whether the Sump is a floor that bears a number or a number that has acquired a floor.

The practical distinction has proved costly. In Year 218 the Office of Vertical Survey renamed the Sump "Terminal 6" for the duration of an expedition and spent the seasons that followed unable to locate it again. The renaming was revoked under First Concordance §9, and Terminal 6 remains an open file.

The Conduit

The Conduit has been stationed on Floor 666 since before the current numbering was fixed. The Librarians decline to state whether the Conduit is a person, a fitting, or an office; the standing entry in the Personnel Register records only the date of posting (Year 12), the hours (continuous), and the note "no relief required." Expeditions reaching the floor report a steady descent of matter arriving from above and passing through the Conduit without accumulation. Two separate expeditions, in Year 402 and Year 509, estimated the rate of passage at 1.4 and 1.6 drachms per minute respectively, and the discrepancy has never been resolved, as neither party was permitted to bring away a sample.

"The Conduit is not to be addressed. It has not been introduced to anyone since the posting was made, and it is not the business of the Archive to introduce it."

— Fifth Concordance, Annex 3, marginal note in the hand of First Reader Valen

Visitors are asked to leave their lamps on the step before entering. This rule dates from Year 288 and is painted on the doorframe; it is not otherwise explained.

Relation to the sumps above

The Sump receives at least four documented inflows. The Oblivion Sump on Floor 5017 funnels desiccation events down the Fifth Spiral Watercourse, which continues as a helical ascent (the designation is inconvenient but immutable) before forming the Renal Rapids and discharging at Floor 666. The G-Sump at the base of Annex Δ yields the page-dust bypass, a narrow conduit catalogued as a subsidiary inflow pending a ruling. Cascading specimens above the Sump are captured by the Sump-Gargoyle network on floors Aperture Beta through Aperture Gamma, whose beta-phase prototypes remain stored on Floors 22.H through 22.M.

What arrives at Floor 666 is understood to constitute a single body of material. The Sump of First Want on Floor 712 is sometimes said to feed the Sump by way of the Aorta of Thirst; this is a misreading of the plumbing, and the vessels on 712 run in the opposite direction. A correction was issued in Year 344 by the Office of Conveyance but was filed in the wrong annex, and the error persists in three floor catalogues.

Logistics and the relief of the floor

Because nothing accumulates, the Sump requires almost no maintenance. The floor is inspected every eleventh year by a party of two, one to carry the tapers and one to carry the ledger. The party descends by the Column Stair to Floor 660, transfers to the service shaft, and returns by the same route within the hour; no expedition has been authorised to remain overnight since Year 291, when a surveyor's assistant filled a page of his notebook with a single unbroken line and was thereafter reassigned to the Oblivion Sump, where the work is said to suit him.

Supplies are not delivered to Floor 666. Nothing has been requested from it, and the Office of Stores regards requisition forms descending below Floor 660 as void at sight.

The Year 312 incident

During the Oblivion Sump Incident of Year 312, the Sump was observed to catalogue material retroactively — that is, matter was found on Floor 666 accompanied by entries describing it, although no descent had been recorded. The Custodians intervened and the entries were sealed. They remain sealed. A reading of the seals was requested in Year 480 under Fifth Concordance §88 and was denied on the grounds that the seals had been affixed to prevent precisely such a reading.

Access

Floor 666 is not restricted. It is merely inconvenient. The Librarians note that anyone who reaches it has, by that fact, been expected.