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[Anton]

I don't know about the four figures, but two of them (those closest to 12 o'clock) are remarkable in that they both sit in tubs with the same ornament. A quick glance suggests to me that it is not common, is it? So why the two tubs are the same? I can suggest the following explanation: The artist began the circle with the right figure, and then proceeded clockwise (alternatively, he could begin with the keft figure and then proceed counter-clockwise). Then when he came to the last figure, he had to use the same ornament as the one he began with, because some pre-defined sequence or pattern of ornaments was in place, and it suggested this very ornament for this last figure.

So what is that pattern, if any?