Glaziers' Guild — The Tower

The Glaziers' Guild is a Grade-II administrative apparatus of the Tower, charged under Concordance 41-B, Annex 2 with the regulation, procurement, and application of Ideational Silica throughout the inhabited floors. It is among the oldest continuously sealed bodies in the archive, and the only one permitted to cut, anneal, or refuse a pane of ideational silica without countersignature. Its headquarters, the Annealed Hall, occupies Floor Xi-114 and has done so since the floor was renumbered in the winter of 1147.

The Guild is overseen directly by the Department of Applied Ephemera, which serves as liaison between theoretical cataloguing and the operational guilds. In practice the liaison consists of a single clerk who reads the Guild's quarterly returns aloud to a sub-committee that is not obliged to be present. The arrangement has never been challenged in writing, which the Margin Commentators Guild notes is itself a form of endorsement.

Mandate and the Luster Scale

The Guild's classification authority rests on Guild Standard 88-Gamma-4a, which defines the Luster Scale: a graduated measure of a silica's capacity to render abstract notions perceptually inert. A pane rated Luster 1 permits a reader to see an argument through it; a pane rated Luster 9 permits the reader to see nothing whatever, including the argument's absence, which is the more commercially valuable condition.

Grading is performed in the Annealed Hall's east range by assessors who work in pairs, one calling the reading and one recording it. The Guild's own returns for 1189 record 41,206 panes graded, of which 312 were re-graded on appeal and 9 were found to have been graded while the assessor was absent. Those nine panes were withdrawn from circulation and are stored, unlabelled, in the Hall's north cellar.

Procurement and the Dream-Mines

Ideational Silica is a meta-stable byproduct of certain classes of Ephemera, and the Guild does not harvest it directly. Harvesting rights are licensed to the Metaphorical Cartographers' Guild, which works the dream-mines on floors too poorly surveyed to appear on the Formal Cartographers' registers. The Cartographers' licence, renewed at intervals the Guild declines to publish, permits the extraction of up to eleven tonnes of raw silica per season, measured wet.

Disputes over what constitutes a tonne are frequent. In the matter of the Second Vein Accord, the Guild argued that the Cartographers had been weighing silica in a vessel the Guild itself had supplied and had therefore been weighing it incorrectly; the Cartographers replied that the vessel had been supplied full. The ruling, recorded in Concordance 41-B, Annex 7, found for the Guild and ordered the vessel emptied, an instruction that has not been carried out and cannot be, the vessel being in use.

Legal interpretation of these instruments falls to the Theoretical Jurisprudence Guild, which the Glaziers consult on immaterial property rights in silica veins. The two bodies have disagreed continuously since 1204 over whether a vein belongs to the floor it occupies or to the dream it was dreamed on.

Production and the Silica Sheeting

The Guild's principal product is Ideational Silica sheeting, formed in the Hall's annealing chambers and credited to the Guild's founding master, Master Anselm Vey, whose method of slow cooling under damp cloth remains in use. The sheeting's most celebrated application is the outer layer of Impervium Sheeting, and the Guild constructed the ideational silica sheeting used for Procurement Ledger Delta-9, a commission now cited in every guild's instruction on how not to specify a tolerance.

The commission required a sheet that would render its contents inert but not invisible; the Guild delivered a sheet that did the opposite, and the Ledger, when sealed inside it, remained perfectly legible to anyone who was not looking for it. The Guild was not found at fault. The Guild of Groundskeepers, who had requested the work, were found to have specified the wrong floor.

The Assessors' Dispute of 1241

In 1241 the Guild's assessors refused to grade a consignment of silica recovered from a stairwell on Xi-114, on the grounds that the material had already been graded and the grade recorded under a ledger entry that could not be found. The refusal lasted nineteen days. The Annealed Hall was closed to visitors throughout, a measure the Guild described as routine maintenance and which the Scribes' Guild of the Middle Floors recorded as the longest closure of a Grade-II apparatus in living memory.

The matter was resolved when the missing ledger entry was located in the binding of a different ledger, where it had been placed for safekeeping by a clerk named Orra Pell, who had since been reassigned to the Inter-Guild Logistical Network Guild. Pell's note, recovered with the entry, reads: "The grade is correct. The consignment is not." The consignment was released without grade and has since been used in the construction of two interior partitions of no importance.

"No silica shall be cut, annealed, or refused on a floor not its own, save by leave of the Hall, entered in the register, and read back to the applicant before the applicant has left the building."

— Concordance 41-B, Annex 9

Relations with Other Guilds

The Guild's standing with the Reflector Guild is poor and has been since the Reflectors declined to return a mirror lent for the assessment of Luster 6 stock; the mirror is still on loan, and the Guild's inventory lists it, in the same hand as everything else, as "with the Reflectors, pending." Relations with the Glasswrights' Guild are complicated by the obvious overlap, which both bodies resolve by not mentioning it. The Dialectic Guild has twice petitioned to have the Glaziers' grading authority reviewed; both petitions were referred to the Department of Applied Ephemera, where they remain.

The Guild publishes no membership list and has never done so. Enquiries concerning the number of its members are directed to the Annealed Hall, which does not answer them. The Guild Hall maintains a standing instruction that visitors to the Guild are to be received courteously and shown the annealing chambers but not the north cellar.