One physical volume holds an Ars Notoria followed by an Opus operum. Treating the two folio ranges as a single undifferentiated “original” conceals the evidence.
The codex changes work at folio 22v
Sloane MS 1712 is one physical volume, but its textual boundary is unusually clear in this thirteenth-century codex. Folios 1r–22r contain an Ars Notoria introduced by a rubric naming Solomon, Machineus, and Euclid. Folio 22v starts the Opus operum with its own rubric, “the notory art which is called the new art,” and a new opening that announces a work of works and a science of sciences. The first text ends with language about appointed lunations, days, and hours; the next leaf begins a different composition. Binding the works together encouraged readers to see a relationship between them, yet adjacency did not erase the second incipit or the new title. The volume therefore records reception as well as contents: someone preserved two methods concerned with revealed knowledge as useful neighbors, while the copy itself still signals where one stops and the other begins.
The first Ars Notoria builds toward theology
The first text distributes its figures across a deliberate late sequence. Grammar appears on 14v–15v, dialectic on 16v–17v, rhetoric on 18r–19r, and geometry begins on the right side of 19r. The sequence then expands into geometric diagrams and symbols across 19v–21v, including hybrid faces on 20r. Folio 22r closes the work with a fifth theological figure containing swords, birds, and serpents. This progression changes both subject and visual vocabulary. Verbal arts lead into geometry, while the final theological image brings recognizable creatures and weapons into the diagram. The catalogue’s count also varies by discipline: three grammar figures, two dialectic figures, four rhetoric figures, and a larger geometric run. That unevenness argues against viewing the notae as interchangeable seals. Each group occupies a particular place in an escalating intellectual and devotional program.
The Opus operum compresses and rearranges the arts
The related Opus operum runs from 22v to 37r and includes six notae of its own. Near its conclusion, folio 36r carries a grammar figure; 36v gathers dialectic, rhetoric, and arithmetic; 37r contains geometry and a “signifier circulus.” This is a different architecture from the first work, where the figures stretch over eight leaves and culminate in theology. Several arts now share a page, and arithmetic becomes explicit in the surviving catalogue description. The comparison shows what “derivative” can mean materially: the later composition keeps the link among prayer, knowledge, and figures while reordering their distribution. It is neither a simple second copy of folios 1r–22r nor an unrelated tract accidentally bound after them. The shared purpose creates continuity; the changed rubric, incipit, figure count, and curriculum create a distinct textual unit.
Columns, colors, and full pages control reading pace
Most of the codex is written in two columns of thirty-five to thirty-seven lines in Gothic script. Rubrics and reserved initials divide the verbal text, while red and brown diagrams, sometimes with green, interrupt that regular page rhythm. Circular, rectangular, and other geometric writing does not behave like prose moving down a column. A reader must rotate attention around borders, compare compartments, and hold several inscriptions together. Full-page figures make the interruption stronger: the ordinary sequence of lines gives way to a surface meant to be surveyed. Color also separates functions. Red can mark structural borders or headings, brown can carry other written elements, and occasional green adds another visible distinction. The manuscript’s intellectual claim is therefore built into its page design. Knowledge is presented through recitation and reading, but also through a disciplined change from linear text to simultaneous visual arrangement.
Worked folio reading: 19r through 22v
The four-leaf turn from 19r to 22v reveals the book’s structure in miniature. On 19r, the last rhetoric material shares a leaf with the beginning of geometry, so one discipline literally yields space to another. The following leaves enlarge geometry into symbols and hybrid faces rather than keeping it confined to one labeled mark. On 22r, the fifth theological figure supplies a visual conclusion with birds, swords, and serpents. Turning the page then exposes the new rubric and incipit of the Opus operum on 22v. The binding makes the transition immediate, but the sequence does three separate things: it closes the verbal arts, develops a geometric interval, and crowns the first text with theology before restarting under the name of a new art. That worked sequence is stronger evidence for the manuscript’s internal argument than a list that simply calls all thirty-seven folios “Ars Notoria.” The physical quire supports that reading. Catchwords elsewhere help a reader follow the gatherings, while this content boundary is announced inside the text itself. The turn from a culminating full-page nota to a fresh rubric would have been conspicuous even without a modern table of contents. It creates an ending and a new beginning within one continuous bound object.