The ancient Chinese method of measuring time were jossticks. Each josstick burn for a specific amount of time. During an event like a fighting contest, the judge would burn a josstick and when the josstick reaches its end, the time is up.

The negative space here is not used to emphasize the subject but rather, give balance to it. The criss-crossed thin smoke is also utilized to show balance (yes, I took 50 shots of the same image just to get the smoke shot I wanted!, LOL)