However, as that was inefficient because of heat lost due to thermal radiation, smoke given off, and fire sputtering in the wind, and so on, kamado made from mud, stone or cement were invented.
が、周辺に熱が熱放射などの形で逃げる他、煙が漂う・火が風で揺らぐなど効率が悪いため、土、石、セメントで作られる竈が発明された。