Irori is the name for a traditional sunken Japanese hearth, often set in a tatami-style room.
Usually square in shape these small pits of burning charcoal were used for rudimentary heating and to warm a metal pot suspended by a hook (jizaikagi) and chain from the ceiling. A wooden fish-shaped lever to raise or lower the pot is common.
Old-style irori can still be found in traditional farm houses and tea-ceremony rooms, where they are used to boil the water for the green tea. One can imagine that irori are potential fire-traps. The word irori is a common name for a Japanese restaurant.
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