For the past year I've been buying organic whole wheat grain and grinding the wheat to make bread. The process is quite easy and the entire grain is reduced to a very fine flour that can be used in making cakes. All of that is to say, it made me wonder, how did our ancestors grind their wheat? Now, I've known about grist mills and have even visited a few but the flour from their was often course.
Here is an excerpt from The Book of Wheat written in 1908 by Peter Tracy Dondlinger. It helps to explain some of the history of the 19th century and the development of grain milling process. He goes on to explain other types of milling processes, high milling, and roller milling.
"Low" Milling.—Before 1850, the millstones in the United States were run at a comparatively low speed, and the grinding was slow. By this date the milling industry had assumed such commercial importance that it was necessary to increase the speed of the stones in order to get the work done. From 1850 to 1875, hard, low grinding was the rule, and the prime object was to make the largest possible percentage of flour at the first grinding. The change in process, due to greater speed, increased the output and improved its quality, "the outcome being a white, soft flour that met with favor in all he leading markets of the world where American winter wheat flours were handled." By this process, however, it was impossible to get the • flour entirely free from contamination, and some of the bran always remained. There were two parts to this old process, reducing the wheat to flour by passing it through a run of stones, and bolting the resulting material in order to separate the flour from the bran and other undesirable parts of the kernei. The percentage of flour obtained by this single grinding depended on four things: (1) The dress of the millstone; (2) the face of grinding surface; (3) the balancing of upper or runner stones; and (4) the speed of the runner. As there was but one grinding, the making of middlings was avoided as much as possible. By this method of milling, some of the bran was pulverized so that it could not be separated from the flour. This gave the flour a darker color, and caused it to gather more moisture, which injured its keeping qualities, especially in moist or hot climates.