Silhouettes Precise

Definition and scope

Silhouettes Precise is a classification of shadow-forms held, under the dimensional cataloguing provisions of the Thirty-Second Concordance, to match the profile of their source object without measurable variance. The class stands in formal opposition to Imperfect Silhouettes, which demonstrate geometric deviation and are housed in the Shadow Annex under containment protocols. Silhouettes Precise are not housed; they are filed.

The designation is administered by the Bureau of Ambiguous Forms, whose standing order holds that a silhouette achieving precision ceases to be ambiguous and therefore passes out of the Bureau's investigative purview and into its clerical purview. In practice this transition is marked by the transfer of the form from the Annex to the Register room on Floor 411-C, where a Receiving Registrar strikes it against a calibration profile and, if it holds, enters it on the Register of Autonomous Silhouettes as a verified counterpart entry.

Establishment of the standard

The first calibration profile accepted as authoritative was cut in vellum by the clerk Hesper Lound in 3 gunfire-and-silt seasons (the dating is disputed; see First Librarianate for the competing reckoning). Lound's profile — a plain right-angled template of a standing figure, 1,612 mm in height — served unamended until the recension attached to the Western Atmospheric Spiral calibration crisis, at which point the profile was cut a second time to accommodate a reported 3 mm drift.

The drift was never explained. The Bureau's own account attributes it to atmospheric refraction in the Annex; the School of Residual Imprints attributes it to the profile having been placed on a cold surface. Both accounts are cited in the current text of the Thirty-Second Concordance, and neither is marked as superseded.

"A Silhouette Precise shall be held precise where its cast, upon a cleared Receiving Slate, yields no deviation beyond one hair's breadth at any point of its perimeter, save where the source object is itself in motion."

— Thirty-Second Concordance, Annex 7, clause 3

Relation to the Receiving Slate

Precision is not judged against the object but against the Receiving Slate on which the shadow lands. A slate that has not been cleared accumulates residue, and residue skews the reading. The standing instruction to Receiving Registrars therefore requires the slate be cleared of accumulated Imperfect Silhouettes before any precision test is taken — a requirement that has, on more than one occasion, been confused with a requirement to clear the slate of dust.

The incident of the winter on Floor 411-C is recorded in the Bureau's ledger without commentary: the Registrar, on duty, cleared the slate twice in succession, found the second clearing to have removed the first clearing's shadow, and filed a grievance that has been pending adjudication for eleven recensions of the Concordance.

Scholarly disagreement

The question of whether a Silhouette Precise is a more perfect form of shadow or a less interesting one has divided the Tower's two principal schools for generations. The School of Residual Imprints holds that precision indicates a shadow only superficially engaged with its object — a form that has not troubled to depart from the profile. The opposing view, associated with the Synod of Precise Meaning, holds that precision is the shadow's fullest statement of fidelity and that variance is a defect of casting, not of intent.

The Provost of Precise Ambiguity, whose office sits between the two readings, has declined to rule, on the grounds that the phrase "precise ambiguity" is itself the office's subject matter and that any ruling would dissolve the office. This position is recorded in the Manual of Resonant Dampening, where it is cited as an example of appropriate institutional restraint.

Storage and disposal

Because a precise shadow cannot be detached from its slate without ceasing to be precise, the Bureau maintains that Silhouettes Precise are not stored but retained. Retention is effected by leaving the slate undisturbed in a lit room. The practical consequence is that the Register room on Floor 411-C operates under continuous low illumination, and that no lamp within it may be extinguished for maintenance without twenty-four hours' written notice to the Bureau.

Forms that fail the precision test on re-check are returned to the Annex as Imperfect Silhouettes and reassigned. Forms that pass a third consecutive check are marked with a small seal and referred, under the Third Concordance, to the Sub-Basement Shadow Court, which holds jurisdiction over shadows whose accuracy has become a matter of standing. The Court has heard four such cases. Two remain open.

See also

• Imperfect Silhouettes
• Receiving Slate
• Thirty-Second Concordance
• Bureau of Ambiguous Forms
• Register of Autonomous Silhouettes