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to begin with man just used grains/wheat. as our minds and technology increased we started grinding the wheat. that was what wind mills where for. the wind spun the propeller and moved a giant stone wheel. a crude convayor belt was under this heavy wheel. the wheat was put onto the convayor belt and went under the wheel, grinding it into flower.
First answer by ID980380211. Last edit by ID980380211. Question popularity: 39 [recommend question]
