In the western spiral arm of our galaxy lies a star system and a planet
occupied ages ago. On one mountain of that planet there is a great
structure, thousands of cubits tall. It is constructed of sapphire and
diamond, is self-repairing, and derives energy from both solar power and
an internal power supply which we still do not understand.

Each solar rotation, this vast mechanism emits a tick. Each hundred
rotations, it emits a gong. Those who study the mechanism believe that
every ten thousand rotations, a small mechanism will appear from a certain
door and make a sound. The last effect has not been observed in living
memory, and the next occurrence is projected to be nearly eighty
generations removed from those now living. Xenoarchaeologists say that
the gong’s period was longer than the lifespan of an individual of that
species, and that the unseen mechanism has a period longer than that
species’ entire recorded history. The entire edifice was constructed only
a few years before that race vanished forever to wherever ancient races
go.

Philosophers across the galaxy have argued over the purpose of the
Eternal Clock. As with other artifacts such as the Diamond Book, the
Circle of Time, the Oracle, and the Wandering Flame, consensus holds
that the motive was not religious or superstitious in nature, but
philosophical.

What principle the Eternal Clock was intended to embody is still a matter
of great controversy. But while arguments rage in the halls of
philosophy, while children are born and great-grandparents die, while
intelligent races evolve and vanish, the Eternal Clock continues to tick.
And perhaps that is the message it is intended to convey.

Curious about the Diamond Book, Circle of Time, Oracle, or Wandering Flame? Read the rest of the story here.