Breath is like the hoop with which a child plays. According to the force of the blow from the stick, so many turns the hoop makes, and when the force is spent the hoop falls down. It is like the ticking of the watch. The watch goes on for the time for which it is wound; it may be for three days or for twenty-four hours, or for a week or a month. Longer than that period it cannot work, because it was not wound for it. Breath is like a child's top. According to the strength with which it is spun so many turns the top makes, each turn helping the other, and when the force is expended the top falls down. In accordance with the first breath, so long will life last: so many breaths.