An Interview with Dr. Robert Frame III, Author of Making Mill City: Flour and Fortune in Minneapolis

Article by Becky Fillinger, photos provided

Robert Frame III                                                             photo credit Emily Ganzel

Robert Frame’s new book, Making Mill City: Flour and Fortune in Minneapolis, is a beautifully illustrated account of the flour mills that revolutionized the global milling industry - and left a lasting imprint on Minneapolis’ culture and architecture. We talked to ‘Bob’ about what piqued his interest in the flour milling industry, the technologies invented here that transformed the industry and why we need to appreciate the story of the flour mills. You are able to purchase the book at local booksellers or online: Making Mill City.

Q:  Minneapolis is often called “Mill City,” but many people today don’t fully understand why. What surprised you most as you researched how the city earned that identity?

A:  I think I was most surprised by how large the Minneapolis mills actually were. I learned that not only were the Washburn A Mill and the Pillsbury A Mill big, but they were both the largest flour mills in the world. They earned that title when built and retained it for years, producing more and more flour each year. Other flour mills in the city were almost as large, but lived in the shadow of the two record holders and received less notoriety. It was a time when that kind of industrial size was the subject of great public interest, something that we don’t see today. The production numbers are staggering. In a single day in 1905, as documented in my book, the Pillsbury A Mill produced 16,113 barrels of flour. That rate of output required 80 to 90 railcars of wheat delivered to the mill each day and 200 railcars to carry off the flour. 

Q:  You’re right - those numbers are staggering. Your book traces how Minneapolis became the world’s leading flour producer. What were the key factors that allowed our city to dominate a global industry for decades?

A:  The key factors were two machines invented and developed in Minneapolis that revolutionized the milling industry, the middlings purifier and the modern roller mill, and the milling systems employing both devices. This occurred in the late 1860s and 1870s. Millers in Minnesota, and particularly Minneapolis, had difficulty milling the locally grown hard spring wheat.  Unlike soft winter wheat grown in the east, which was easy to mill and produced very white, bran-free or speck-free, flour, hard spring wheat had a brittle bran that was difficult to mill without having it being reduced to fine particles that were difficult to sift out. This was especially problematic because the hard spring wheat produced flour with a higher gluten content making it much better for bread, which all flour buyers at the time wanted. But they wanted it to be very white, without bran specks. The middlings purifier allowed the processing of the hard spring wheat through a series of grindings and air-assisted siftings to remove the bran. The purifier-processed flour then proved to be dramatically better than winter wheat flour and sold for a higher price. The middlings purifier was followed a few years later by the new roller mill, with pairs of metal rolls that replaced the traditional millstone. The new roller mill, accompanied by the purifier, fit into an advanced system that allowed millers to produce great volumes of the spring wheat flour, making higher profits, grinding and selling larger and larger quantities.  This prompted millers to build larger and larger mills, especially in Minneapolis, where the waterpower of St. Anthony Falls was used to power the giant new mills.

Q:  The story of milling is often told through famous names like Washburn and Pillsbury. How did you try to broaden the story beyond those well-known industrialists?

A:  The Washburns and the Pillsburys have come down to us as “millers,” because their names are connected with the famous flour mills.  But they were not actually millers. They were mill owners and investors. They did not operate milling equipment.  Those who did the actual milling were known as “practical millers.” The practical millers did the hands-on work in the mills. They were accompanied by millwrights, milling engineers, and many others who were needed to run the vast milling systems.

The millers, engineers, and millwrights were the individuals who designed the milling techniques and the inventions that transformed the industry. The story I tell in the book is a narrative of technology, machines, and processes in the mills themselves, rather than a business history of the many flour mill companies. It was all part of what we know as the Industrial Revolution at the time, when we went from an agriculture economy to one based on modern industry. 

Q:  What do we know about the daily lives and risks faced by the workers inside those enormous mills?

A:  One of the book’s sidebars is titled “Life in the Mills: Hot, Dark, and Dangerous.” The Minneapolis mills were crowded together on long, narrow lots to take advantage of the limited areas of available waterpower from St. Anthony Falls. The mill buildings of the 1870s and 1880s had thick stone walls and small windows. There was little air circulation to cool the heat from the milling machines. And there was little light except near the windows, and that was limited too. No mill had electric lights until the Pillsbury A Mill in 1881, which was the first electrically lighted flour mill. And in the dark, hot interior, the milling machines were crowded together. Unlike modern factories today, the turning gears, wheels, and leather belts had no safety guards. At the same time, millers often wore loose-fitting clothing that was easily caught in the machinery.  Severed fingers and limbs were not uncommon. 

Q:  Were there particular individuals you encountered in your research who deserve more recognition in Minneapolis history?

A:  Probably the single most interesting individual I found was William C. Edgar, the longtime editor of the Northwestern Miller, the milling trade journal. First published in 1873 as an advertising piece in La Crosse, Wisconsin, the Northwestern Miller soon moved to Minneapolis as the industry here expanded.  It quickly broadened to a full trade journal and hired Edgar as the editor. The Miller was published every week for a century from 1873 to 1973. Edgar decided it should cater to individual millers in addition to the industry generally. He added fiction and art to its pages, getting original material from noted artists and writers of the day, like Mark Twain.  In addition, the Miller carried news stories and notes about everything in the industry, small and large.  Almost anything in milling history can be researched in its many issues. 

Q:  You’ve spent decades studying industrial history and historic preservation. What first drew you to the story of Minneapolis milling?

A:  In 1976 I was hired by the Minnesota Historical Society (MNHS) to study the state’s surviving waterpower flour and grist mills because the Society wanted to add a mill to their Historic Sites Department. It was an 18-month project and in that time, I found and researched a number of valuable historic resources that had been barely used before. Among them were the back issues of the Northwestern Miller and the business papers of Otis A. Pray and William C. Edgar.  Edgar was the long-time editor of the Northwestern Miller and Pray was a millwright who was instrumental in building and supplying many of the important early mills in Minneapolis. 

Q:  Why does the story of flour milling still matter to Minneapolis today?

A:  The flour milling history of Minneapolis is significant because it is what put Minneapolis on the world map. It explains why names like Pillsbury and General Mills continue to be known worldwide today, even though the mills and buildings that gave birth to those names are no longer operating in the city.  

Q:  What lessons about innovation, industry, or urban growth can modern cities learn from the rise of Mill City?

A:  Appreciate the city’s heritage before it disappears. At any one time between the 1870s and the 1930s, Minneapolis had 20 to 25 flour mills actively turning our vast quantities of fine flour for the world market. Today there are only five original mill buildings remaining, none of them operating. There might have been even fewer, had the Minnesota Historical Society not stepped in to save some buildings after a devastating fire in the 1990s. Fortunately, that effort was successful. The Mill City Museum now occupies the space within the remaining walls of the National Historic Landmark Washburn A Mill, directly across St. Anthony Falls from the National Historic Landmark Pillsbury A Mill, converted to artist lofts.