Department of Epistemic Cartography

Standing and jurisdiction

The Department of Epistemic Cartography is a bureau of the Tower charged with the survey, description, and custodial upkeep of knowing itself as a terrain — beliefs, their routes, their collapsed passages, and the terraces on which they are held. It is the sole body administering the Type 1 classification and the strict protocols attached to catalytic holdings, and it handles all catalytic materials and information referred to it by other bureaus. Its working authority derives from the Provisional Manual of Epistemic Protocol, which remains provisional in name only; the Manual's fourth recension has governed the Department since the winter of Floor 411. The Department occupies Floors 718 through 741, excluding Floor 729, which is jointly held with Department of Cartography and is used for the drying of rubbings. Its reading room admits visitors between the third and ninth hour; visitors are requested not to lean on the ledges, which are load-bearing only under specific readings.

Administration of catalytic holdings

A Type 1 (Catalytic) holding is one whose presence alters the standing of adjacent holdings — a shelf of ordinary claims, once shelved beside it, will restate themselves. The Department's protocols for such material are exacting. Each catalytic item is stored in a lead-lined slipcase within a sealed alcove, and the alcove is photographed on the first day of every month. The photographs are stored in a separate wing, because the original photographs, when left adjacent to the items, began to caption themselves. The Guild of Epistemic Foundations regulates the initial intake of catalytic material and works in close correspondence with the Department, though the two have disagreed since the 19th Concordance over whether an item that has already catalysed its neighbours requires re-classification or merely a firmer shelf. The Office of Epistemic Transit draws on the Department's outputs to route unowned beliefs between floors; its carriers are instructed never to read a catalytic label aloud on a stair.

"No clerk shall uncase a Type 1 holding without first noting, in the margin of the register, the name of the clerk who last cased it, whether or not that clerk is still on the roll."

— Provisional Manual of Epistemic Protocol, clause 44, Fourth Recension

Relation to the Cartographic bureaus

The Department maintains a firm boundary with the wider cartographic family of the Tower. It shares floor-rights and rubbings with Department of Cartography, and its staff occasionally sit on the joint oversight of Ephemeral Cartography. It is not to be confused with the Department of Noetic Cartography, which was a bureau of Cartography and whose records were absorbed elsewhere; nor with the Department of Vertical Cartography, which charts the Tower's rises and descents and has no claim on epistemic slopes. Correspondence with the Bureau of Contradictory Cartography is conducted in duplicate, by standing order of the 7th Concordance. Its most productive and least stable relationship is with the Bureau of Concordant Cartography. The two exchange quarterly indexes of settled beliefs. In the Year of the Ninth Landing, an index arrived containing entries that had not yet been written in the Department's own register, and were written only after the arrival of the index. The matter was referred to the Department of Temporal Cartography and remains open.

Floor 729 and the Epistemic Spiral

Floor 729, withheld from general Departmental use, adjoins Floor 303, where the Tower's catalogue of recursive knowledge is kept. Staff assigned to 729 report that the adjoining stair transmits a faint ticking, most audible when a holding on the Epistemic Spiral is amended. The ticking has been catalogued once, as a sound, by the Department of Acoustic Cartography, and once, as a doubt, by this Department; the two entries do not agree on the hour. The Department's own survey of Epistemic Architecture — the built form of beliefs within the Tower — was undertaken on Floor 729 and published in a folio of 112 plates. Plates 61 through 64 were withdrawn before distribution, on the grounds that they depicted corridors which the Department had not, at the time, agreed to have. They are held in the sealed alcove, photographed monthly.

Disputed points

The 19th Concordance states that the Department's authority over catalytic materials is "primary and exclusive." The 31st Concordance, Annex 6 states that the authority is "primary, excepting matters of transit, which pass to the Office of Epistemic Transit at the moment of hand." Hand, in practice, has been interpreted as the instant a carrier's foot leaves the tread, and as the instant the slipcase clears the alcove's threshold. The two readings have produced seven adjudications and one very quiet stairwell. A second dispute concerns the Department's founding date. One account places it at the signing of the Provisional Manual of Epistemic Protocol; another, favoured by senior clerks, places it considerably earlier, on the grounds that the Manual was written to describe an office already centuries in operation. The Guild of Epistemic Foundations maintains a third date, which it declines to commit to paper.

Notes on visiting

Catalytic holdings are not shown to general visitors. Researchers holding a Contingent Epistemic Visa may view a single item per sitting, under supervision, and must not take notes in pencil; graphite, it was found, travels.