Comments by "GTW" (@gtw4546) on "Appalachian People How they Heated their Homes back in the day" video.

In places known for very cold winters like Russia, Finland, and Sweden, they'd build fireplaces with a maze of passages that redirected the smoke and hot air to warm the bricks before eventually going out a chimney. The rest of the house was built around the massive masonry heater. They minimize the amount of wood needed by using heat as efficiently as possible and a section of these fireplaces was used for cooking and baking.
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