Floor Ω

Floor Ω is the terminal lettered floor of the Tower's eastern spiral and, by the reckoning of the Office of Vertical Registry, the last floor on which a name may be lawfully inscribed. It occupies the whole of the spiral's closing turn, a little under two hundred metres of shelving set behind a double seal at the head of the Omega Stair, and is administered jointly by the Librarians and the Keepers of the Terminal Register. Unlike the numbered floors — whose sequence cannot be reconstructed by any method yet attempted, and which place Floor 9090 between Floor 1801 and Floor 101 without evident difficulty — Floor Ω is named for a letter and carries no number at all. It is reached from Floor 111 by the Eastern Spiral, and from nowhere else. The Office of Vertical Registry records this in its standing inventory as "a terminus of one approach, not of the building" (Registry Schedule Ω-1, folio 3).

Nomenclature and the sealed plate

The floor takes its designation from the plate riveted to the lintel of its single door: the Greek capital omega, cast in brass and surrounded by the words λ δ — "the end of the road." Second Concordance, Clause 44, fixes the spelling of the floor's name in all documents as "Floor Ω" and forbids its transliteration into Latin letters on the grounds that "the letter is the floor and the floor is the letter." A minority report appended to the same clause by the Committee on Lettered Holdings disputes this, observing that the plate is brass, the letter is Greek, and the floor is shelving; the report was received and filed without being adopted. Clerks in the Registry continue to write "Floor Omega" in pencil on the backs of transfer slips. The practice is not forbidden, but no transfer slip written in pencil has been honoured at the door since Concordance 118 took effect.

Holdings

Floor Ω holds no books. Its shelves carry instead the closed cases of the Terminal Register: some nine thousand volumes in which the Tower records the names of subjects catalogued on floors that have since been withdrawn. A subject is withdrawn when its floor is renumbered and its name cannot be carried over. The case is then closed, sealed in green wax, and walked up the Eastern Spiral to Floor Ω, where it is shelved in the order of its arrival and never again in the order of its floor. The Register is therefore the only part of the archive arranged by time rather than by number, a fact the Office of Vertical Registry describes as "an irregularity we have chosen to call a method" (Registry Schedule Ω-1, folio 11).

The cases are not read. They are weighed, annually, by the Weighing Office, whose returns are entered into the Register's endpapers in a hand that has not changed in four hundred years. The most recent return, for the year just closed, records a total of 41,208 kilograms and a discrepancy of eleven grams against the previous year, which the Weighing Office attributes to "atmospheric conditions at the head of the stair" without further argument. The Committee on Lettered Holdings has twice asked why the cases are weighed at all. The Weighing Office has twice replied that the question is out of order.

The Omega Stair and the visiting rule

The Omega Stair rises one hundred and eleven steps from the landing at Floor 111 to the plate on Floor Ω. It is the only approach, and it is narrow enough that two persons cannot pass except at the seventh and ninety-fourth steps, where the wall recesses. Visitors are admitted between the second and ninth hours and must sign the door register in ink, not pencil. They are asked not to touch the cases, not to read the endpapers, and not to remain on the stair after the ninth hour has struck, as the lamps are extinguished from below and the descent is made in darkness by the stair's own custom.

The stair has been the subject of one sustained dispute. Third Concordance, Clause 9, holds that the stair "ascends to the floor and is not of it," placing it under the jurisdiction of the Office of Vertical Registry. Second Concordance, Clause 51, holds the reverse: that the stair "is the floor's threshold and its outermost shelf," placing it under the Keepers of the Terminal Register. For ninety years both offices collected a stair tax from the same visiting scholars, each on the authority of its own clause. The matter was settled in the winter of the year recorded in the Register as Ω-90, when the Office of Vertical Registry and the Keepers agreed to divide the proceeds by the step on which the visitor was standing when asked to pay. The seventh and ninety-fourth steps, being recessed, were assigned to neither office and have since been maintained at joint expense. The arrangement is not recorded in any Concordance and is observed exactly.

Scholarly disagreement

The central question of the floor is whether it is the Tower's last or merely its last lettered floor. The Office of Vertical Registry maintains the latter position and cites the existence of floors numbered above it — Floor 2001, Floor 202, and the disputed Floor π — as evidence that the spiral closes while the building does not. The Keepers of the Terminal Register maintain the former, on the ground that "a floor without a number cannot be followed, and a floor that cannot be followed is a floor that has ended" (Keepers' Memorandum on the Status of Ω, article 2).

Third Concordance, Clause 77, appears to support the Keepers but does so in a sentence that the Committee on Lettered Holdings has shown to be a scribal duplication of Clause 76, which concerns the binding of ledgers. The Committee's finding has not been accepted by either party. A third position, advanced by the Society for the Study of Unnumbered Floors and never formally answered, holds that the question cannot be settled from inside the spiral and proposes an expedition to descend the Omega Stair and continue past Floor 111 in search of a further letter. No such expedition has been mounted. The Society's subscription list has not been renewed since the year recorded as Ω-90, and its correspondence is held on Floor Ω, unread, in the order of its arrival.

Inventory of the floor

The Keepers' annual return lists the floor's fixed contents as follows:

• Nine thousand and forty-one sealed cases of the Terminal Register, shelved by arrival.
• One brass plate, riveted, bearing the omega and the words λ δ.
• Two seals at the head of the stair, one Librarian's and one Keeper's, renewed each year on the same day.
• One door register, in ink, beginning at the year recorded as Ω-1 and continuing to the present folio.
• One chair, for the Keeper on duty. The chair is not to be moved.

The return notes in its margin that the chair has been moved twice and that both instances were resolved by the Office of Vertical Registry without recourse to the Concordances. The floor is closed on the day the seals are renewed.