It's like pulling a pin out of the gears of the clock, to allow them to turn in a synchronized manner.

My visage high above your city,
Shines like gold, but half as pretty.
Arms I've none, but hands I've two:
Mondo, mini, black not blue.
Climb my stairs and have no fears,
All that threatens are my gears.
Tucked beneath the mightly wheel,
An envelpe shall truth reveal.

There is a dynamic interplay between circadian rhythms and metabolism. You don't eat while you are sleeping, and the body needs to take this into account.

The time it takes for that to happen determines the length of the cycle-roughly 24 hours-and keeps the clock going.

Just turn back the clock nine years. It was the same thing with Tiger.

We had to turn the electricity and that wouldn't allow us to make lunch.