Japanese bowl with nesting upper bowl with drain hole in bottom?

Just purchased at auction a Satsuma bowl. The bottom portion is beautifully painted. There in a nesting upper bowl which is less ornate and has a hole in the bottom about 1″ diameter.

Anyone know the use of such a bowl?

Quantum Raven 15lbs.
$9.99 (1 Bid)
End Date: Thursday Apr-24-2014 7:49:33 PDT
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