WINNOWING

'Wind winnowing' is a agricultural method developed by ancient cultures for separating grain from chaff. It is also used to remove Weevils or other pests from stored grain.
In its simplest form. it involves throwing the mixture into the air so that the wind blows away the lighter chaff, while the heavier grains fall back down for recovery. Techniques included using a winnowing fan (a shaped basket shaken to raise the chaff) or using a tool (a winnowing fork or shovel) on a pile of harvested grain.
In Ancient China the method was improved by mechanisation with the development of the rotary winnowing fan, which used a cranked fan to produce the airstream.^[1] This was featured in Wang Zhen's book the ''Nong Shu'' of 1313 AD. This technique was not adopted in Europe until the 1700s, when winnowing machines used a 'sail fan'.^[2]
The development of the winnowing barn allowed South Carolina rice plantations to increase their yields dramatically.

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See also

References

See also

★ Winnowing Oar

★ Chaffing and winnowing

References

1. The Question of the Transmission of the Rotary Winnowing Fan from China to Europe: Some New Findings, Hans Ulrich Vogel, 8th International Conference on the History of Science in China
2. Broadcasting and winnowing, Antique Farm Tools