Arbre

First Appearance and Context

Arbre is referenced during the winding of the great clock at a math’s Mynster, when the central meteorite weight is described as being made of the same material as the heart of the world. Other clock weights of carved stone are said to have been quarried from the Cliffs of Ecba and hauled over the North Pole, situating these practices geographically on Arbre. The term also frames in‑world dating conventions such as A.R. seen in citations.

Description and Role

Arbre is the world that contains the walled scholarly enclaves known as maths and the wider “extramuros” society beyond their walls. The narrative so far places daily mathic rites, studies, and engineering within this world’s physical and historical setting. The Mynster’s astronomical and timekeeping works—driven in part by a nickel‑iron meteorite described as "made of the same stuff as the heart of Arbre"—highlight the planet’s geophysical analogy and its role as the reference body for local observances and calendars.

Periods of stability and upheaval are hinted at in accounts of visitors being admitted when conditions outside are orderly, and in references to times described as post‑apocalyptic, during which maths focus on self‑sufficiency. Mentions of the Three Sacks indicate past crises severe enough to interrupt normal operations of the clock, though details remain sparse.

Relationships and Functions

• Serves as the setting for the mathic tradition and its institutions, including the Mynster where the clock and star‑observing apparatus are housed.
• Provides the frame for the in‑world era notation A.R., used in scholarly references like entries of The Dictionary.
• Contains geographic features such as a North Pole and the Cliffs of Ecba, from which building stone for clock weights is quarried.

Current Status

Arbre is inhabited and active: maths conduct regular rites and maintenance of the clock, and controlled visitation from extramuros has been permitted in recent times when conditions allow. Broader political and historical details remain limited in the narrative to date.