Site hosted by Build your free website today!

The Page Begins Here

Automated Flour Milling Evolves into New Process Milling 1820-60

The Cooper Mill was built in 1826, to replace a mill built by Isiah Younglove which operated until 1788. Then Elias Howell of Chester ran a saw mill and grist mill on this site until 1825. Then in April of that year to settle Elias Howell estate, the mill lot was deeded to Nathan Cooper for a sum of $750 dollars. This included approximately 4 1/2 acres of land, a mill dam, a grist mill and a saw mill.

In 1826 Nathan Cooper built the present mill to replace the earlier one. The new mill had two water wheels, each driving two sets of millstones. The mill was modeled after the design and ideas of Oliver Evans which were contained in his book, "The Young Mill-Wright and Miller's Guide." This new process used a system which was known as "automatic," that used a system of moving elevator belts, and screw conveyors, and a hopper-boy.

In the 1850's, the old wooden water wheels of the Cooper Mill were replaced by metal water powered turbines manufactured in Batley, New Jersey. Well past the Civil War, the mill still contained a number of its Oliver Evans' inventions. In fact the mill may have been converted into a "new process" milling operation.

In 1913 the Cooper Mill of Milldale (Milltown) was the last operating mill in Chester Township, and its milling operations were "about to be discontinued." In 1963 the Morris County Park Commission purchased the property and began the restoration of the mill. The Cooper Mill was opened to the public in October of 1978, and Ivins Smith has been the miller there ever since.

Automated Flour Milling Evolves into New Process Milling 1820-60
Theodore R. Hazen.

What this discussion is about is the improvements to the Automated Flour Milling System. Sometime after 1800 the automated flour milling system would become known as the "Old Milling Process." Mills which operated during the period of 1800 to 1860 were mainly by the automatic flour milling system, low or flat grinding.

A number of factors effected the rate of increase in the number of grist and flour mills. They are the wheat supply, number of water powered sites available, the number of men with capital willing to develop these sites, and the Napoleonic Wars. Water power sites was always plentiful, but men with capital and technical skills was not. The technical experts, the millwrights were found in the states and backwoods of the United States.

From the period of 1800 to 1860 there was a great variety of "mill architecture" based upon functional demands. The automated flour milling system of Oliver Evans had a great impact on mill architecture with his book, "The Young Mill-Wright and Miller's Guide." Its greatest impact was in the material handling of grain. There was no longer a need for an exterior sack hoist, sack hoist hood attached to the upper gable end of the mill above a series of Dutch doors located on each level of the mill. There was also a great difference between the long established (pre-Oliver Evans mill), larger grist and flour mills found in the well established settlements of the United States and the so-called "backwoods" of America.

The first mills were usually small, made of local material to suit local needs at the time. They were hastily built on water powered sites that often dried up during the summer months. Sometimes there was no written claim of water rights or records. Then a more elaborate mill would have been constructed. Often a larger grist mill which also served local needs. There were grist or custom mills, merchant or commercial mills, plantation and combination mills built across the United States. (Note: Explain the operation and differences of each type of mill)

A Custom Mill: The man who builds the mill usually operates the mill and makes repairs to it himself. The mill owner's house is also the miller's house. The miller does not have a costume or clothing separate from his normal clothing. The clothes he wears to work the farm or his other trade is also the same that he wears working in the mill without changing them in between. The mill operates seasonally usually only at harvest time. The miller-mill owner has another trade or several of them that he practices other times of the year. The miller also usually dresses his own millstones. Usually the miller's apprentices or helpers are his children. What the miller knows about his trade he learned form others and has little time to read about his trade from books or trade journals. The miller may or may not keep a record of his business operation and customers. Often the miller uses the fabric of the mill to record his tally or customers. A custom mill usually has only one or two pair of millstones, usually never more than two. The mill if they have two pairs of millstones has one for corn and one for wheat. Usually these millstones are domestic and not imported French millstones. The mill usually does not have complicated machinery. Often it does not have the machinery to clean before it is ground or sift the grain after it is ground. The corn and wheat leave the mill most of the time unbolted. The farmer brings the grain to the mill in a sack and once it is ground the miller places it back into other same sack. The mill is operated on a barter system of the miller collecting a toll for payment of grinding grain. The mill does batch grinding for farmers and local individuals on a first come, first serve basis. The mill does not clean up in between each batch of grinding grain. Sometimes the mill only grinds corn, but may also grind animal feeds. In lowlands and tidal areas they produce grits and in the mountain area they produce buckwheat or pancake flour. The Piedmont they may produce both, or one or the other. Often it only cleans and dresses the millstones when it is seasonally closed.The mill grains grain relatively slowly and has a small output. Custom mills are usually small and are not permanent buildings made out of stone or brick. The miller may have a horse and wagon but depends upon his customers for transportation of the raw grain and final product. The mills are build in rural and isolated areas.

A Merchant Mill: The man who builds the mill for the owner is a millwright. The owner is not usually the same person who constructed mill. The mill owner employs millers to operate the mill and at times housing is provided for in a "miller's house." The mill operates years round, it is larger and has more complicated machinery. The mill has a complicated system of storing grain, cleaning it and sifting it once if is ground. The mill usually has three or more pairs of millstones. The mill has a hires or employees millstone dressers who job it is dress millstones. Usually every week one of the pairs of millstones need to be dressed, so usually once a month every pair of millstones is dressed. If the mill has apprentices or helpers they often live with the miller in the miller's house as if they were his own children. The mill employs specialized labor force, millers, millwrights, millstone dressers, cleaners and oilers, warehouse and packers. The miller wears a costume (which is often white) and clothing separate than his street clothes. Usually in the late 19th century the miller would go to school to learn his trade and read milling books and trade journals, rather than solely learning his trade though apprenticeship. The mill keeps complete records of grain purchased, grains ground, products made, waste and lost, and other business records. Some times in larger merchant mills the miller's office is in a separate building and employs secretaries and office personal. The mill uses imported French millstones for the production of white flour. The mill only grinds white flour for profit and export. The mill operates on a system of profit or loss. The mill buys grain from farmers and grain dealers. The mill packages its products in commercially manufactured barrels and sacks often with its own logo or brand name on it. The mill operates on or close to a 24 hour a day, 6 day a week basis. The mill has a large daily output and is measured in how many barrels or sacks it can produce in a 24 hour period. The mill building are larger often built of stone or brick often with separate additional grain storage units. The mill often has separate warehouse and granary buildings. The mill has its own system of transportation (wagons, dock, canal, trucks, or rail siding) for bringing raw grain to the mill and delivery of the final product to the market. The mills are build close to the grain supply areas and export markets.

Plantation or Estate Mill: This type of mill usually is a mixture of both a custom mill and a merchant mill. They are operated as a custom or feudal milling operation for those living on or working on the plantation or estate. These mills collect a toll for the grinding of grain for those living on the plantation and like the feudal system the owner receives a portion of that income. They also operate a merchant trade flour milling business and the barrels may be produced by individuals living on the estate or plantation. If they use cloth flour sacks they are woven also by people living on the estate or plantation. These mills also usually does a merchant milling operation for the export of white wheat flour. These mills grind grain grown on the estate or plantations and from others neighboring estates that may not have a milling facility. Since they are operated on the old feudal system of milling the mill owner is not the builder and he employs a miller or millers to operate the mill. Housing, livestock and a food allowance is often provided. The mills usually have two pairs of millstones. A domestic pair of millstones for grinding grain for those individuals living and working on the estate or plantation. Another pair of millstones is usually a French millstones used for grinding wheat and producing white flour, and only flour making machinery. These mills were often build in the tidewater areas or close to transportation. In size and character they more closely resemble feudal mills of Europe but may be larger buildings depending how important the exporting of flour is to the owner occupation.

Combination Mill: This type of mill usually is a mixture of both a custom mill and a merchant mill. This type of mill often began its operation as a traditional custom mill, but for various reason has taken on also the merchant milling operation. One reason is that it may be trying to compete with the modern white flour industry in Minneapolis. Another reason is that is may be just outside of large centers of urban population, and merchant milling offers a regular source of income for the mill owner and the miller. This type of mill often may have a domestic pair of millstones and a pair of French Millstones, or it may have added the modern system of roller milling to the mill so it can manufacture Minneapolis style white flour. Often the mill owner will employ a miller of the operation of the mill may be a sole function of one of the mill owners children while other children operate other parts of the owners business ventures.

Oliver Evans system of automated flour milling and his devices had a great effect upon "mill architecture." The mills needed to grow in height due to the elevators and in width and breath for additional millstones and the other improved machinery when it was installed. Merchant mills (competitive mills at the front of flour production in the United States at the time) were in the best position to take advantage of the new technology and to adopt it early on. Many mills of the period and of the mid-Atlantic States were constructed of stone. They often need to add an additional floor for the height required for the elevators. (Examples of these mills would be the Grist Mill at Lobachsville, in Oley, Pennsylvania, and the Burwell-Morgan Mill in Millwood, Virginia.) Mills of the period grew significantly in height which can be attributed to the method of milling that makes use of gravity (at no cost), and the automated flour milling devices of Oliver Evans. (Examples of these mills would be the Chapman Mill (1858), located in Thoroughfare Gap on Broad Run, Virginia, and the Pickwick Mill (also 1858) outside of Winona, Minnesota. Both mills are 6 story limestone buildings. The earlier Chapman Mill built upstream on Broad Run was smaller stone building.)

Oliver Evans may have effected "mill architecture," but it was the millwrights who interpreted it. They studied the the numerous variable of water mill site, and applied Oliver Evans rules for water powered grist and flour mills to them. They plugged in the information supplied by the owner and came up with as to the size, height of each mill, the features of entrance and exit the water, the mill road or approach for convenient loading and unloading of grain into the mill. The millwright decided from the information they had at hand for each mill how to design it as a custom or merchant mill work and how much, the type and quantity of t he products, and the machinery required for that particular head and quantity of water, the material of construction, etc.

The best mill foundation material was that of stone, at least as high as it was exposed to water. This depended upon the type and location of the water wheel, whether if it was located outside of the mill, inside of the mill or between two sections of mill buildings. The later turbine water wheels required a low basement. An overshot water wheel required a high basement stone work extending as high as the water wheel was in diameter to at least the top of the sluice box. Another main factor in locating a mill was to have the main floor above the level of the road and mill yard so that it is located at the exact height of a wagon bed so it would be convenient to load and unload grain at the main mill door. Each additional floor varied in height depending upon the machinery that occupied that floor. The first floor had to have high enough height to it to accommodate the lifting and turning over of a millstone by a millstone crane. It is easy to determine which mill originally never had a millstone crane because the later added cranes cannot lift and upturn the runner stones.

A mill is made more fireproof by building it of stone or brick and placing the floor timbers into slots or sockets in the wall that have burnout ends cut on them. This is so if the building has a fire, they would fall away from the walls without taring them up or prying down the walls with the fire. Interior walls of the first floor were often plastered with mortar upon the stone. Stone lintels were placed over each door and window opening on the outside but but contained wood on the inside. The most important structural feature in a mill was l the basement "husk" or "hurst frame that would hold the millstones. It was built extra strong, often with more craftsmanship than the building that protected it. This frame work supported the millstones on the floor above. In William Carter Hughes book, "The American Miller and Millwright's Assistant," he stated that errant millwrights framed the millstone platform to the main building. It should be separate so that the millstones can stay level, so power is not lost and so the building would not be effected by the vibrations. Often the millstone platform foundation goes deeper into the ground than that of the mill building. Mr. Hughes warned that the millstone platform post should be no taller than 12 feet so that unnecessary tremors from the millstones and gearing would cause the machinery to work off pitch. Henry Pallett, "The Miller's Guide," recommended the use of cast-iron millstone platforms in 1852, which were already found in England. (Guilden's Mill in Bladen, Pennsylvania, on Maiden Creek which was built in 1791, with its attached miller's house of 1792, is a German mill with round wooden turned pieces that make up the millstone platform. These large round wooden turned pieces are found throughout the mill and can also be seen in the horse frame of the millstone furniture.) David Craik, "The Practical American Millwrights and Miller," advocated that timbers be removable when decayed so they can be replaced, without disturbing the walls or the upper portion of the mill building. The mill gearing occupied the interior space of the millstone platform with the millstones located above and the water wheel next to it (whether it is inside the mill or outside). Vertical water wheels gearing occupied more space and the gearing of water turbines was less cumbersome.

The first floor is where the millstones were located and was often called the stone floor or the grinding floor. A small room was partitioned off as the miller's office were a desk, chair, stove, shelves for books, business records, and accounts were stored. Sometimes the shelves were larger enough to form bunks were the miller and his helpers could sleep if they worked later into the night. The upper floor were often more open, arranged with machinery according to the flow plan of the mill designed by the millwright to fit inside of the mill according to Oliver Evans. The first floor had a receiving hopper, the millstones, flour bins, flour packers, and the miller's office. The mill's basement had the fireplace for heating branding irons, and the millstone platform. The second floor had grain and flour bins and bolters. The upper attic floor had the hopper-boy, grain cleaners (smutters and rolling screens) and perhaps an old fashioned sack hoist. The ending stones are not always located on the mill's first floor, they are often located on the middle floor(s) or located in the attic. The same is true of hulling stones, they can be located in the upper floors along with the cleaning machinery. (An example of this can be found in the Rensselaerville Grist Mill, Rensselaerville, New York, which has a pair of hulling stones for buckwheat on one of the upper floors.) Each machine was linked together with another one by a system of chutes (spouts), elevators, conveyors (augers), and from one story to another through an automated system. Located amongst this was floor and dust rooms. The flour rooms being for rodent proof storage and the dust rooms to allow the dust to settle in an airless environment. Trapdoors improved the passage of mill furnishings in and out of the mill since stairs were often narrow, steep, and risers were often scalloped with wear. Safety guards were basically unknown for many years to protect the mill staff and the public from accidents caused by revolving pulleys, belts, shafts, and mill gears.

In "mill architecture" the standard size mill is 40 by 50 feet, a rectangular shape. Sometimes they are 40 by 60 feet, but still a rectangle. Many mills have later additions. These were made to increase their original output, and for technological changes. With stone or brick mills the additions were sometimes wooden frame structures added onto the original one. Sometimes they were of the same material (either wood, stone or brick) and only a thin line runs up the building separating the later addition. An important irregular feature of a normally rectangular mill building was the wheel house. From northern Virginia, through Maryland and Delaware, up into Pennsylvania and New Jersey it was common to find the water wheel located inside of the mill. This was necessary where the climate was extreme. Sometimes the water wheel was simply covered with a roof. (This may have been the case with the Lee Mill, Stratford Hall, Westmoreland, Virginia, and the classic "Winter at the Old Grist Mill," a Currier & Ives print.) A water wheel either located inside of the mill, in a wheel house, or under a roof, would possibly keep the wheel ice-free. When a mill was later modernized with a water turbine often they were located inside of the old water wheel pit. Space is opened up within side of the mill because the machinery is then belt driven. Generally auxiliary steam engines (and later other types of engines) were housed in additions, which were often constructed of fireproof material if the mill was of wood construction. The style of mills of this period were governed by functional considerations. Mills more than any other structure conformed to the saying, "form follows function," and installing the Oliver Evans system of automated milling did more for that than any other technological change in the flour milling industry and history.

In "mill architecture" roofs were usually gabled, sometimes gambrelled or hipped, or Dutch-roofed, or mansard. Dormers were added to illuminate the loft and attic areas. Sometimes a clerestory monitor was constructed to let in full illumination to the attic. These opening besides letting in light also let out heat during the warm summer months. (The mill of Capt. D. W. Barger, at Shawsville, Virginia, pictured in the classic 1928 Fitz Water Wheel Company, Hanover, Pennsylvania, catalog shows a mill with a clerestory roof.) Windows were casement and double hung for light and ventilation. When a water wheel was located on an outside wall, fewer windows were located on that side of the building to shield the mill from dampness and cut down on the noise of an old creaking water wheel. A pulley hoist was often located at or near the roofs ridge enclosed in a sack hood. This was located on the side of the building where the delivery wagons unloaded grain and machinery to the mill. (An interesting exception is the Chapman Mill, (1858), located in Thoroughfare Gap on Broad Run, Virginia, where a stone projects from the building that holds a sack hoist pulley. There are four floors above this level, and two below the first floor.) A facade of Dutch doors on each story sacks could be pulled from the vertical hoist located underneath the hood. Sometimes located either above or at the threshold of each door was a wooden roller (as wide as the door opening) so sacks could be moved from one floor to another. The classic mill facade is found in pre-Oliver Evans and also in some post-Oliver Evans mills.

Keystone Mill, Edinboro, Pennsylvania, built as a "new process" flour mill. William Culbertson in 1801 had John Campbell construct a log grist mill a distance down stream from the dam. In 1802 William Culbertson built a saw mill across from the grist mill. Shortly afterwards another saw mill was built at the dam on the west bank. The Culbertson Mill was a small crude log structure, operating using the low milling system. The Culbertson Grist Mill was the third grist mill built in the county. In 1856 William Culbertson's son who operated the mill, sold the Culbertson Mill to James Reeder and Isaac Taylor. In the same year they replaced the first mill with a new mill, installing modern merchant milling machinery of that day. The modern machinery incorporated the Oliver Evans automated flour milling system along with the "new process" flour milling technology. The new mill was built on the same site by Mr. Skelton using Greek Revival Architecture.

Reeder and Taylor operated Keystone Mills for many years. The mill was very prosperous until the turn of the century when they sold the mill. From then on Keystone Mill saw a great number of owners. The last miller to dress and use the millstones of Keystone Mills was George Brookhouser. Mr. Brookhouser came from a milling family, it was his father who was one of the owners and operators of the Venango Roller Mill. George Brookhouser operated The Keystone Mills while in town his wife ran a store. Keystone Mills had roller mills when Mr. Brookhouser ran the mill but he was the last active miller to use the millstones there.

The last miller to operate the mill as a flour mill was Pearly C. Harned (pictured above standing alone to the right of the front drive though). Mr. Harned gave the mill its red coat of paint with white trim. In large white letters was painted "Keystone Mills, Edinboro, Pa." Painted above the drive of the loading dock. Mr. Harned ground wheat flour but by far his buckwheat flour was the most popular. Mr. Harned added a steam engine to the south side of the mill for when the water level was low during the summer months, it had a tall metal smoke stack which stood above the mill from a small shed added to the building. When Mr. Harned sold the mill, the new owner converted the mill to a feed mill.

The sound structure was demolished in October of 1959. People thought they could push the mill down, but the quickly learned they had to dismantle it peg by peg. The old mill went to a sad grave to become land fill between the two Edinboro Cemeteries. In the mill were "Black Cherry" beams 18 inches square, some of them up to 50 feet in length, all going into the land fill.

For a photo of before it was painted "red" when it was painted "white" around 1900, see: F.A. Drake's Mill, near Cambridge Springs, Pennsylvania.

Oliver Evans did not become Outdated,
the Systems of Milling Changed.

Perhaps one factor that contributed the most to the change in the system of mills, was not found within the mill, but was the water wheel. During the period of 1800 to 1860 the greatest advancement in knowledge available to millwrights came in the area of water wheels. The vertical water wheels under went improvements to increase their efficiency. And speaking of efficiency it was in this period, that the Franklin Institute during the 1840 discovered the means of determining a water wheels efficiency. Also cast-iron began to replace wood in must of the traditional water wheels. The European Greek or Norse water wheel that had evolved into the American tub wheel because the French development of the water turbine. Also during this period larger conventional vertical water wheels were built since the development of the noria water wheel several thousand years ago. During this period millwright and miller's guides were published along with scientific journals that spread information faster than ever before in milling history. In 1824, M. Poncelot of France advocated curved buckets in undershot water wheels which lessened the shock and increased the water wheel's efficiency. A Poncelot water wheel changed the efficiency of an undershot from 25-30 percent to 60 per cent. According to Jay M. Whitham, in "Water Rights Determination, From an Engineering Standpoint," the Poncelot water wheel was never in extensive use in America, having about the same efficiency as a breast shot water wheel.

Ventilated water wheel buckets were an improvement of Sir William Fairbairn, a British engineer who applied his knowledge to breast and overshot water wheels. The more use of iron in water wheels was first advocated by John Smeaton and John Rennie in late 18th century England, in both water wheels and smaller mill gearing. The British millwright John Rennie designed a sliding hatch for high breast shot water wheels. Then in 1824 William Fairbairn improved upon them. In the 1840, after water turbines were developed in France, they were very shortly afterwards manufactured in New England. In the United States the first all-metal water wheel was patented by Samuel Fitz in 1852, was made in the Martinsburg shops in (what is now) West Virginia. The Henry Burden water wheel, built in 1852 in Troy New York, was the most powerful water wheel in the world. The Burden water wheel had a diameter in feet of 62.0, a breath or depth in feet of 22.0. Its bulk was 56,000 cubic feet, and its R.P.M. was 2..5. The final capacity or output in horsepower was 300 and the water wheel weighted 250.0 tons. During this period the majority of mills were run by water power which was still cheap and abundant in comparison to steam power.

Mill gearing became more and more made of cast iron, and then later belt driven or "belt gearing." Just after the turn of the 1800's traditional oak water wheels driving pairs of millstones still may have turned wooden cogs or gear teeth of maple or hickory, millstone pinions were being made of cast-iron. During the 1820's more metal was being used for water wheels (shafts and hubs), and by 1830 more cast iron was being used for mill gearing. In David Craik, "The Practical American Millwrights and Miller," he describes in 1870 a mill he had seen in the 1850's or 1860's that was a complete cast-iron cog and tooth gearing with no leather belting. He said the mill was over geared, with a pinion fitting into a too small of segmental gear that was too close to the water wheel. The problem was that the gears always needed to be greased.

Leather belting or leather gearing had its advantages over cog gearing. In many ways, cog gearing was cheaper and less troublesome, and more durable than leather belting, it was preferred by millers and mill owners because it smoother motion and less wearing (on millstone dress, and could produce more flour from a bushel of wheat). Some advantages of leather belting is: More even motion, steadier operating millstones, and less strain exerted upon the water wheel. Leather belts were quilter with less noise, and belted mills were simpler and easier to keep in good running order. Millstones and machinery could be better placed inside of the mill, and it meant the reintroduction of the mill machine: the portable burr mills. If leather belting worked well with water power it worked better with steam power.

During this period of 1800 to 1860, the scope of the millwright's job changed as more cast-iron machinery, mill parts and furnishings appeared. At one time, most machinery was completely fabricated or handcrafted of wood near or at the mill site by apprentices and the master millwright, with the help of the blacksmith, and later more and more foundry work. The millwright would now consult with the mechanics at the foundry and mill furnishers about the purchase of any mill parts. The interior machinery became more complex and new principles were applied that challenged the millwrights too keep up with the latest inventions. During the period of 1795 to 1860, there was only one millwright's guide and handbook, "The Young Mill-Wright and Miller's Guide," by Oliver Evans in 15 editions. The first book to come after Evans was "The American Miller and Millwright's Assistant," by William Carter Hughes, first published in 1850. The first book to really update Oliver Evans was David Craik, "The Practical American Millwrights and Miller," first published in 1870.

The "miller" which the word is derived from the word, "mill," was the operator of the grist or flour mill. He was the "grinder." If the mill required two or more hands, the miller would have an apprentice. The milling guides outlines the separate duties of the head miller, second millers, third millers, and mill hands known as "dusties," " sack boys," "hopper-boys," "boys," and flour packers. The number of mill hands depended greatly upon the number of millstones the mill had and the amount of grain ground. Grist or custom mills operated seasonally and often used farm or local labor which was hired on a day or week basis, while the head miller was hired for the long term period. In "The American Miller and Millwright's Assistant," William Carter Hughes outlined the duties and proper help needed for a mill with four run of millstones, using the automated flour milling system. ("Duty of the Miler") The head miller or mill superintendent took charge of the mill's business. He examined each millstone's progress and making necessary improvements in each. He came on duty after breakfast and worked until 11 p.m. at night. The second miller is capable of taking charge in the absence of the head miller. The second and third millers dressed the millstones by four p.m. each day, swept and followed the instructions of the head miller. The mill hands oil, the journals daily. A clerk will take care of the business and is someone "competent to take in wheat," which means inspect it before delivery and payment made. A careful person is used for packing flour. In Henry Pallett, "The Miller's Guide," there is more specific duties of the head miller. ("Duty of the Miler")The head miller must see that there is enough clean grain for night grinding, test the millstones, and appoint someone to dress them, if necessary each day. The second miller tended to the mill until one in the morning when the third miller took over from then until one in the afternoon.

in a small mill the head miller responsibility was not only to operate the mill, but to keep it clean, and in good repair, the dressing of the millstones, accounting and managing all of the mill hands. The miller maintained a good relationship with the farmers and the mill owner. Successful millers gained a good reputation in the community as well as having a good personality, with skill, character, and integrity. Of greater importance was the miller's honesty, to wind the confidence of the farmers and the mill owner. In Henry Pallett, "The Miller's Guide," he says, "If the owner of a mill is not a practical miller himself, yet he may form some idea of the capability of the miller from examining the quality of the flour made."

Some millers had the mechanical and inventive ability to made improvements in the mill's machinery. Many millers were capable of doing good work but were handicapped because of inadequate machinery in the mill. (for example Adams Mill, along Rock Creek. It was always breaking down and the owner was putting more money into the mill than it produced as saleable product.) In Henry Pallett, "The Miller's Guide," he warns millers not to be "governed by the mill owner as to the time the stones should be dressed." Since mill owners often want them to run a longer time without dressing so no time would be lost, even when it resulted in poor flour quality. "A miller should have it in his power to to take up stones and dress whenever necessary," Henry Pallett, "The Miller's Guide." Millers should know how to dress millstones and to promise not to drink. (This is the problem George Washington had with three millers one after another that lead to his death.) Miller's houses should be built for family use near the mill. Millers may live in rooms or apartments but it is more desirable that they live in a house next to the mill to serve as a watch over the mill when it is idle.

The Reduction of Flour by the Regrinding of Middlings.

A Simplified Plan of David Bonnell's Process of Making Flour by Regrinding Middlings. Patented in Canada, 1849-50 (patent number 279), this method used (F. G.) first grind, a pair of traditional millstones (C.D.) to produce "chop." The product of the first millstone grinding designated term for the meal or stock. The "chop" falls into the bin marked (F. T.), where an chop or meal elevator lifts it up to the discharge chute marked (G) were a cooling rake (C. R.) or hopper-boy (H. B.) is located in a cooling room. The cooled chop falls through the floor into the scalping bolts (S. C.). There the flour bolts or screens separate the coarse from the finer particles. The tailings, the larger coarser stock that pours out of the tail of the flour bolt or screen, as opposed to the "throughs," the finer particles, they are reground by the auxiliary stones (A. G.). From the auxiliary stones (A. G.) the reground chop goes into a series of middling bolters (shown on the two floor below). These bolts are for flour bolters used for separating merchant flour and bran.

Note: The above illustration is a schematic drawing, and meant to show the operation of David Bonnell's process. In practical reality the components may be located more compactly within a structure and make more use greater numbers of elevators, conveyors, and chutes, than what is shown in this implied example.

The change in the systems of milling was brought about by the increased application of Oliver Evans' ideas. At one time the miller's threw the middlings into the mill stream with the bran. Oliver Evans advocated the regrinding of middlings with fresh wheat. Middlings does not mean from the middle, but from the middlings. An expression of the medium quality of the meal.

One of the reasons the change in milling is called "new process" of milling is that the middlings are reground now on separate millstones called "middling stones," and are bolted on reels by themselves. The mill and the system of milling is essentially the same s those of Oliver Evans with the exception of how the middlings are reground. Now instead of being mixed with fresh wheat they are ground on separate smaller diameter pair of millings known as "middling stones." The regrinding of middlings created a second grade quality of four. Often the flour was "killed" by the closeness of the hot millstones. Flour that was "killed" has injured gluten and will not rise when baking, and not make good bread. The flour looses its "life" and its ability to create air bubbles when being baked.

Millstones were operated using the "old low" or "flat milling system" where the millstones were run relatively close together, thus producing a lot of hot damp meal. Even with the introduction of "The Young Mill-Wright and Miller's Guide," by Oliver Evans, the method of milling remained relatively the same. Millstones were sharply dressed, running fast, and close with a lot of pressure on the grain to produce as much flour in just one grinding as possible with as few middlings produced as feasible. Milling happened in three phases or basic steps, cleaning, grinding, and bolting. In practice, the stages often were cleaning, possibly recleaning again, grinding, cooling, bolting, regrinding and cooling again, for a final bolting.

To avoid the loss of selling middlings as third or lower grades of flour, such as "red dog" or "ships stuff," many methods of regrinding middlings was tried. Evans recommended that middlings be reground by themselves, or along with fresh grain on regular millstones so that they would not be over heated or killed. One solution was offered by an American "meal man" by the name of David Bonnell who in August of 1849 in the United States and in 1850 in Upper Canada, patented his "improved process of flour milling." In "The American Miller and Millwright's Assistant," William Carter Hughes discusses Bonnell's improved process of flour milling, patented August 14, 1849. If the millstones are set high much of the best portions would be lost. If the millstones are set close the heat produced by friction spoils the flour. It is necessary for a double grinding process.where the middlings would be separated and reground. A mill should have a second set of millstones for regrinding middlings (turning a rapid motion, from 300 to 500 revolutions per minute). The millstones should be adopted to do this type of work, a 36 inch diameter pair would be suitable for a four run mill. It should be gear driven because belts would slip, with a conical eye, with irons put in to leave as much room as possible. the eye should be covered with sheet iron or tin. The millstones should be strongly banded and should have deep furrows at the eye or the center. The feed should be changed from that of the hopper, shoe and damsel, to a funnel, tube and screw. The tube reaches down into the eye almost to the bale. Inside of the tube is a turning screw in place of the damsel that pulls the material from the funnel down the tube into the stones.

David Bonnell of the Tecumseh Mills, described the process as this. "The first grinding warms the product, and on being passed up the elevators, through the cooler (hopper-boy) and first bolts, the offal is comparatively kiln-dried, when it is subjected to the rapid motion of the auxiliary mill, and on being bolted, is is readily divested of almost every remaining particles of flour...... There is nothing new in grinding over the offal, or bran, on the contrary, that has long been practiced. This, of course, I would not deny, as I do not claim to be the discover or inventor of any new principle. I only claim to have adopted the grinding process to the practical and continuous operation of souring or cleaning the offal with auxiliary mill, adapted to that purpose, and running very rapidly, and, by a simple construction and arrangement, to have made the feeding of the offal uniform and perfect, and that by those means all the difficulties here before encountered in attempting to grind offal are entirely overcome... When the whole meal is sent to the first stones and to the cooler (hopper-boy) the bran should not be cut up so fine as when attempting to get all the flour from the wheat by one grinding......The "offal" (middlings) after being reground, is not "returned" to the "hopper-boy," or the first bolts, but sent to the return or duster bolts." The miller may decided to return the flour to the cooler (hopper-boy) or the first bolts, to be incorporated into the superfine flour. In a custom mill the process would be adapted so a small pair of millstones 20 to 24 inches would be sufficient for regrinding the middlings driven by belting.

In Henry Pallett, "The Miller's Guide." he advocated three methods of regrinding middlings, two similar to Oliver Evans' method, and the third similar to that of David Bonnell's patented process method but less harsh. Pattlett's third method was to use a special stones for middlings, of 3 to 3 1/2 feet in diameter. The millstone texture is close and the dress specifically different and the speed slower to 130 revolutions per minute. The treatment of middlings is more gently reground and with less pressure and heat than Bonnell's so less flour is likely to be killed. In David Craik, "The Practical American Millwrights and Miller," he says, "the greatest trouble in all large mills appears to be the working of the middlings." Millers avoided grinding high (with the runner stone set "high" above the bed stone), and they made one first-class grade of flour and two or three grades of middlings. David Craik advocated using one run of middling stones to regrind middlings into first-quality flour. Then a second pair of middlings stones would mill the second middlings into a second quality flour, or mixing the lower grades, depending upon the quality of the middlings. A mill should have five pairs of wheat stones and two pairs of middling stones with a six reel chest of bolts plus two three reel chests and three flour coolers.

Oliver Evans hopper-boy was often installed in mills using the old flat milling system and the automated process. It passed out of favor when the "new process" changed from the "half-high milling" to 'high milling" in the second second half of the nineteenth century (after 1870). In time force flour bolts and dusters would be designed to separate the flour from the dust. Flour exhausts and new types of coolers replaced Oliver Evans' hopper-boy to speed up production. The other of Oliver Evans automatic devices continued to be installed to save time and labor. A new process of milling would after 1860 be adopted, "gradual reduction" or "high milling." which would go through several stages in its evolution from the original to an adaption of the French process of milling and bolting wheats.

According to John Storck and Walter Dorwin Teague's book, "Flour for Man's Bread, A History of Flour Milling," believes that "new process" milling main factor in its development was the purifier. So according to their principals, "new process" milling began in the 1870's, and there is no mention of David Bonnell's "improved process of flour milling." There is a lot of information that we just don't know about his period in history, but there is one thing that we do know, as least during this time we now record the names of the millers more than any other era in the history of milling.

Bramanville Grist Mill, a.k.a. Caverns Creek Grist Mil, and the Howes Cave Mill.

Note: Thjis mill is one of the best examples of a "new process" mill, it is the Caverns Creek Grist (Howes Cave or Bramanville) Mill, Howes Cave, New York. The mill is on the National Register of Historic Places located on Caverns Road off Route 7, east of Cobleskill, New York. The mill demonstrations that you do not have to have a large building to install a "new process" flour milling system.

The mills has four pairs of millstones and an auxiliary pair of millstones on an upper level. The mill was powered by four water turbines, that may have been removed during one of the past world war scrap metal drives along with the entire millstone drive train. This is unfortunate because it renders the mill unable to operate or effectively grind grain.

Program's Source: Interpretive programs, slide lectures, and milling sifting demonstrations by Theodore R. Hazen, Master Miller (mill operator), Millwright, Curator of Molinology, Site Supervisor, and Lead Interpreter, Pierce Mill, Rock Creek Park, National Park Service, National Capital Region, The Department of the Interior, 1984-1995.

Program References:

"Grist and Flour Mills in Ontario From Millstones to Roller Mills, 1780's-1880's," by Felicity L Leung, Department of Canadian Heritage, Parks Canada, 1976.

And other books mentioned in the above text.

Return to Home Page

Copyright 2003 by T. R. Hazen