Water flowing over a water wheel, or around a turbine
would power the mill.
The weighed grain was dumped into bins on the lower level.
Then an elevator made of an endless belt with metal buckets attached to
it would take the grain to bins located on the top level. The grain would
then be gravity-fed into millstones or a flour roller on the main level
which did the actual grinding.
The milled product falls into another bin on the lower level
where another elevator carried it up to the bolter on the top level.
As the bolter vibrated, the flour sifted through increasingly
bigger holes so that it was sorted into its various grades, and stored in
its respective bin.
Chutes from each bin ran to the main level, where the flour
was bagged.