What keeps time?

Heartbeats
steps
a circle, pulled through its circumference
a jar, beneath some papers, in a cupboard
a tick
a dinosaur, reshaped and reappraised
rings on a tree
waves, microwaves, and train goodbyes
the folded hands of a pensioner
and the regular occasional ha
ha
ha
of air rising to meet air.

But where, tell me, does all this kept time
earn its freedom?
Is it waiting
in the gap between the bells,
or is it already taken
from the stretched skin
beating one, two, three, four?