What the hell is this? The machine that used to mop rice?

Hehe, this is called windmill, which is used to sort rice. Is to put the dried millet into the upper bucket and use it to separate the full millet from the flat millet. There are fan blades at the position of that round hole, and turning the handle is equivalent to a blower. This skill is widely used in rural areas, and there may be room for it now.