A machine for separating seed from chaff, &c.; a fanner. A machine with revolving vanes, used in various forms, for particular purposes, as for winnowing grain, for blowing fires, for producing ventilation, and the like;- called also fanning-machine. — Webster, 1882
The fans whirred inside the mill, a cloud of chaff blew out its front, and the kernels of clean wheat poured out of its side… – Farmer Boy, Chapter 25, “Threshing”
Prior to the invention of mechanical devices, the wind was used to winnow. Wheat or other grain was piled on bare ground on bare ground outside; it was tossed into the air, and the chaff was blown away while the heavier grain fell to the earth. The first mechanical fan – meaning device used to move currents of air – was men using hand-held “fans” that were waved to create artificial wind. These first fans were usually no more than pieces of canvas that were flapped while the ends were held in the hands.
There were many who believed that man was rebelling against God by separating wheat from chaff in this way, because it was man’s moral duty to wait patiently for a natural wind. It was considered shocking to produce wind in calm weather, when clearly God intended for the air to remain still. In some civilizations, the use of any sort of fanning device for winnowing was sufficient cause for excommunication from the Church.
The mechanical fanning mill (fanner, fanning machine, winnowing machine, or grain separator) was invented in the early 19th century as a wooden case holding a machine with rotating arms with vanes – similar to a windmill – to produce a blast of air that passed through a contained channel. Material to be separated, such as the beech leaves mixed with the beechnuts from Farmer Boy, were fed into a hopper, and gravity caused the material to fall into the machine and into the path of the air currents. A series of sieves (or riddles) of varying fineness were positioned in front of the blast, and these sorted the settling material into finer and finer heavier particles as the lighter, and usually undesirable, particles were blown out the side. Early fans were rotated with a hand-crank, like the ones the Wilders owned. Some could be attached to a horse-power or run by steam engine. Often, farmers shared a single fanning mill; it was moved from farm to farm as needed.
The drawing above shows the working parts of a typical fanning mill. A handle was on the outside of the wooden housing at the toothed gear, and when turned, rotated the fan blades. In addition, it vibrated the sieves. Not shown are two air intake openings, one on each side. These could be opened or closed in order to regulate the amount of air passing through the machine. The winnowed grain was collected beneath a spout (located at the green dot). Cross section from Edward Henry Knight, Knight’s American Mechanical Dictionary (New York: Hurd and Houghton, 1877), 825.
19th Century Fanning Mills. The advertisements at left below appeared in newspapers dating from the time of Farmer Boy. The advertisement at right below is from the 1894 Montgomery Ward catalog. The navigation button that brought you to this page shows a photograph of a restored 1880s mill.
fanning-mill (FB 2, 22, 25), see also winnow