Pete,
I'm not sure what is the experiment, technique, pyro work or handle arrangement.
I can see that at the top rim and base the pyro does not go all the way around, but the bamboo drawing is excellent.
I must admit, when I first saw this it rang a bell with something else I'd seen elsewhere, nothing to do with Les but the 12 Disciples carried by musket men. They contained the measured amount of black-powder for each shot. The larger one is for fine powder for the strike pan.