Time proceeds as if walking down an endless spiral.
Twenty-four hours constitute one day, seven days one week,
four weeks one month, twelve months one year. Time is divided by human
beings with all these units we've invented. Though time moves forward
along a straight line, it is these units that bend the line into a
spiral, creating an illusion of circularity. “Spiral” is a
clock that consists of four spirals of different revolutions,
respectively representing day, week, month, and year. Moving subtly and
infinitely, it resembles time passing by.