Coriander's Clock

One of the Arcanaeum's most famous, mysterious and popular items, Coriander's Clock is a mainstay on the desks of arcanists and pretentious nobles alike.
One of the very few humans to be granted entrance to Anthur-Ro, and the only one known to have been granted a mastery in any discipline, let alone three (clockwork, astronomy and divination), Coriander Cole was an unparalleled genius in her time, just over 400 years ago.
There are no shortages of theories as to what ultimately drove the great arcanist to madness. Some believed it was eldritch voices from beyond the stars that only she had the skill to hear. Many believe she was pushed to it by an uncharitable god that demanded that this artifact beyond the ken of mortals be built. The least fun historians believe it was a function of underlying mental trauma under the pressures of every rich and powerful individual on Oa demanding exclusive use of her gifts.
According to some, however, Cole remained quite sane through the end of her short life but was so driven by the scope of the work she had undertaken that it rendered every one of her other interests and the external demands on her time (like food, language and hygiene) entirely irrelevant.
The bottom line is this: her work was a success, the clock works, and it's a verified miracle of astronomical and artificial brilliance.

Genius of the Clock and its Complications

Entire careers at Anthur-Ro are built in theorizing upon the interrelationship of the specific parts of Coriander's Clock. No credible master as yet has dared to publish upon a theory of the whole.  
Every now and then there is a breakthrough whereby some natural phenomenon or arcane event can be synchronized to a delay gear or the tension of a flywheel. In one particularly revelatory article, Professor Gloriana Slateshod at last identified the purpose of a nearly microscopic anti-magic field set behind the Tear Sapphire and on the superior aspect of the balance bridge governing what was otherwise identified as being a complication tracking Regni's orbit. Professor Slateshod theorized, and later a team of her students proved, that its purpose was to minimally, and on an irregular basis as it traced the outline of the bridge, disrupt the flow of arcane energy from the oscillator within to an enigmatic elliptical ratchet far to the rear of the case that otherwise interacted with nothing but transfer cogs. The interdisciplinary team of students was able to verify in a monograph-length publication that the effect of the antimagic field was to slow the complication replicating Regni's orbit by precisely the gravitational effect of Oko upon that much more distant moon: a nearly negligible gravitational phenomenon.
Perhaps the most celebrated breakthrough study, conducted at the Planar Gates with an observational team over a period of eight years, identified a icosahedric complication floating in an antigravitic double-axis tourbillon as having snapped to reveal a different face at the precise moment that a cubic gate was triggered by the opening of the portal to the Elemental Plane of Water. A second movement correlated 211 days later with the opening of the portal to the Ethereal Plane, verifying that the Ceramic Icosahedron's purpose was to identify the timing of the opening of the Planar Gates. Although there is a small constituency of scholars that believe that to be the purpose of the Clock, the overwhelming majority point to the numerous unexplained complications, the arcane tension the positions of the Icosahedron exerts on the core tumblers, the fact that the Icosahedron is barely visible when the Clock is fully assembled, and, of course, the bell, as evidence that it is merely a complication providing an element of a greater equation.
It was this breakthrough that really shone a light on the deep brilliance of the object, as it required Cole to have personally inferred not only the timing of the opening of the Gates (which had never previously been identified) but to have intuited their cause such that their irregular openings could be timed in advance through mechanical means. Anthur-Ro has yet to identify even a contributing factor to that phenomenon, which Cole clearly understood and never recorded.

Reproductions

Cole's notes are summary in nature. She left behind schematics and basic instructions that allowed the clock to be reproduced with relative ease. With the exception of the Tear Sapphire, no expensive components are necessary to construct a copy and no spellcasting above third level is required to animate it. Not only do numerous artificers create replicas each year in an attempt to better understand and analyze the Clock, but kits are also sold to hobbyists with an interest in creating the most complicated machine on Oa. Pure artificers are often less taken by the scope of the Clock's output but by the simplicity of its construction, such that even an intermediate-level artificer could put one together reliably given a few years of free time in the evenings.  The Circle has not restricted dissemination of replica Clocks in hopes of encouraging new discoveries.

Mystery of Purpose

The central question of any student of the Clock is, of course this: what does it do? Immediately apparent to any user is that the clock does not keep time moving forward.  It is a countdown timer. When the hands reaches their apex, the sterling silver bell rings and the clock resets itself to begin counting down again. In the nearly 400 years since Anthur-Ro has been keeping track, the clock has reset itself to periods of time as long as 26 years, three months and change, and as short as 17 days, eight minutes and 12 seconds. Because the event being counted down to remains a mystery, the interval between bells seems to have been predictable only to Cole.  
New clocks can be tested by checking their reset against existing verified accurate clocks. Every properly built Coriander's Clock on Oa is synchronized with every other.

Item type

Magical