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77-636: The museum was conceived in 1998 and is located in the Old Mill Building, a stone gristmill building of the former Pine Grove Iron Works . It is the first museum in the United States dedicated to a hiking trail. The museum opened in 2010. The museum is open each year from early April to late October. Parking is available adjacent to the Furnace Stack Picnic Pavilion. Admission is free. The museum also operates

154-752: A collection of custom made hiking sticks honoring the Inductees. The 2011 Charter Class included Myron Avery , Gene Espy , Ed Garvey , Benton MacKaye , Arthur Perkins and Earl Shaffer . The 2012 Class included Emma Rowena "Grandma" Gatewood , David A. Richie, J. Frank Schairer , Jean Stephenson and William Adams Welch . The 2013 Class included Ruth Blackburn, David Field, David Sherman, David Startzell and Everett (Eddie) Stone. The 2014 Class included A. Rufus Morgan, Charles R. "Chuck" Rinaldi, Clarence S. Stein and Pamela Underhill. The 2015 class included Nestell K. "Ned" Anderson , Margaret Drummond, Stanley A. Murray and Raymond H. Torrey. The 2016 class

231-413: A husk. This foundation isolated the building from vibrations coming from the stones and main gearing and also allowed for the easy re-leveling of the foundation to keep the millstones perfectly horizontal. The lower bedstone was placed in an inset in the husk with the upper runner stone above the level of the husk. American inventor Oliver Evans revolutionized the labor-intensive process of early mills at

308-399: A large head compared to other types of wheel which usually means significant investment in constructing the headrace. Sometimes the final approach of the water to the wheel is along a flume or penstock , which can be lengthy. A backshot wheel (also called pitchback ) is a variety of overshot wheel where the water is introduced just before the summit of the wheel. In many situations, it has

385-412: A mechanical sieve to refine the flour, or turning a wooden drum to wind up a chain used to hoist sacks of grain to the top of the mill house. The distance between the stones can be varied to produce the grade of flour required; moving the stones closer together produces finer flour. This process, which may be automatic or controlled by the miller, is called tentering . The grain is lifted in sacks onto

462-446: A mill pond, which is formed when a flowing stream is dammed . A channel for the water flowing to or from a water wheel is called a mill race . The race bringing water from the mill pond to the water wheel is a headrace ; the one carrying water after it has left the wheel is commonly referred to as a tailrace . Waterwheels were used for various purposes from things such as agriculture to metallurgy in ancient civilizations spanning

539-438: A number of blades or buckets arranged on the outside rim forming the driving car. Water wheels were still in commercial use well into the 20th century, but they are no longer in common use today. Uses included milling flour in gristmills , grinding wood into pulp for papermaking , hammering wrought iron , machining, ore crushing and pounding fibre for use in the manufacture of cloth . Some water wheels are fed by water from

616-586: A percentage called the "miller's toll". Early mills in England were almost always built by the local lord of the manor and had the exclusive right (the right of mulcture ) to a proportion on all grain processed in the community. Later, mills were supported by farming communities and the miller received the "miller's toll" in lieu of wages. Most towns and villages had their own mill so that local farmers could easily transport their grain there to be milled. These communities were dependent on their local mill as bread

693-544: A poem by Antipater of Thessalonica , which praises it as a labour-saving device (IX, 418.4–6). The motif is also taken up by Lucretius (ca. 99–55 BC) who likens the rotation of the waterwheel to the motion of the stars on the firmament (V 516). The third horizontal-axled type, the breastshot waterwheel, comes into archaeological evidence by the late 2nd century AD context in central Gaul . Most excavated Roman watermills were equipped with one of these wheels which, although more complex to construct, were much more efficient than

770-449: A reversible water wheel was by Georgius Agricola and dates to 1556. As in all machinery, rotary motion is more efficient in water-raising devices than oscillating motion. In terms of power source, waterwheels can be turned by either human respectively animal force or by the water current itself. Waterwheels come in two basic designs, either equipped with a vertical or a horizontal axle. The latter type can be subdivided, depending on where

847-434: A system that allows the sequential milling of these grists, noting that "a mill, thus constructed, might grind grists in the day time, and do merchant-work at night." Over time, any small, older style flour mill became generally known as a gristmill (as a distinction from large factory flour mills). Modern mills typically use electricity or fossil fuels to spin heavy steel, or cast iron, serrated and flat rollers to separate

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924-414: A vertical axle. Commonly called a tub wheel , Norse mill or Greek mill , the horizontal wheel is a primitive and inefficient form of the modern turbine. However, if it delivers the required power then the efficiency is of secondary importance. It is usually mounted inside a mill building below the working floor. A jet of water is directed on to the paddles of the water wheel, causing them to turn. This

1001-484: A water wheel. The mechanical engineer Ma Jun (c. 200–265) from Cao Wei once used a water wheel to power and operate a large mechanical puppet theater for the Emperor Ming of Wei ( r. 226–239). The technological breakthrough occurred in the technologically developed Hellenistic period between the 3rd and 1st century BC. A poem by Antipater of Thessalonica praised the water wheel for freeing women from

1078-407: Is a simple system usually without gearing so that the vertical axle of the water wheel becomes the drive spindle of the mill. A stream wheel is a vertically mounted water wheel that is rotated by the water in a water course striking paddles or blades at the bottom of the wheel. This type of water wheel is the oldest type of horizontal axis wheel. They are also known as free surface wheels because

1155-597: Is assumed that the scientists of the Museum of Alexandria , at the time the most active Greek research center, may have been involved in its invention. An episode from the Alexandrian War in 48 BC tells of how Caesar's enemies employed geared waterwheels to pour sea water from elevated places on the position of the trapped Romans. Around 300 AD, the noria was finally introduced when the wooden compartments were replaced with inexpensive ceramic pots that were tied to

1232-507: Is needed. Larger heads store more gravitational potential energy for the same amount of water so the reservoirs for overshot and backshot wheels tend to be smaller than for breast shot wheels. Overshot and pitchback water wheels are suitable where there is a small stream with a height difference of more than 2 metres (6.5 ft), often in association with a small reservoir. Breastshot and undershot wheels can be used on rivers or high volume flows with large reservoirs. A horizontal wheel with

1309-615: Is probably the Barbegal aqueduct and mill where water with a 19-metre fall drove sixteen water wheels , giving a grinding capacity estimated at 28 tons per day. Water mills seem to have remained in use during the post-Roman period. Manually operated mills utilizing a crank-and-connecting rod were used in the Western Han dynasty . There was an expansion of grist-milling in the Byzantine Empire and Sassanid Persia from

1386-408: Is the overhead timber structure and a branch to the left supplies water to the wheel. The water exits from under the wheel back into the stream. A special type of overshot/backshot wheel is the reversible water wheel. This has two sets of blades or buckets running in opposite directions so that it can turn in either direction depending on which side the water is directed. Reversible wheels were used in

1463-495: Is used for wheels where the water entry is significantly above the bottom and significantly below the top, typically the middle half. They are characterized by: Both kinetic (movement) and potential (height and weight) energy are utilised. The small clearance between the wheel and the masonry requires that a breastshot wheel has a good trash rack ('screen' in British English) to prevent debris from jamming between

1540-481: The Ancient Near East before Alexander's conquest can be deduced from its pronounced absence from the otherwise rich oriental iconography on irrigation practices. Unlike other water-lifting devices and pumps of the period though, the invention of the compartmented wheel cannot be traced to any particular Hellenistic engineer and may have been made in the late 4th century BC in a rural context away from

1617-755: The Ebro River in Spain is associated with the Real Monasterio de Nuestra Senora de Rueda , built by the Cistercian monks in 1202. The Cistercians were known for their use of this technology in Western Europe in the period 1100 to 1350. Although the terms "gristmill" or "corn mill" can refer to any mill that grinds grain, the terms were used historically for a local mill where farmers brought their own grain and received ground meal or flour, minus

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1694-640: The Hellenistic Greek world , Rome , China and India . Waterwheels saw continued use in the post-classical age , like in medieval Europe and the Islamic Golden Age , but also elsewhere. In the mid- to late 18th century John Smeaton 's scientific investigation of the water wheel led to significant increases in efficiency, supplying much-needed power for the Industrial Revolution . Water wheels began being displaced by

1771-722: The Ironmaster's Mansion Hostel , a hostel and special events venue located near the midpoint of the Appalachian Trail just a few hundred yards from the museum. The Appalachian Trail Hall of Fame was established by the museum in 2011. Each year the museum's Hall of Fame selection committee selects one or more persons to be inducted into the Hall of Fame. Nominations for inclusion are accepted each year using an online survey site. Those eligible for inclusion include anyone who has made an exceptional and positive contribution to

1848-483: The Roman Empire by the end of the first century BC, and these were described by Vitruvius . The rotating mill is considered "one of the greatest discoveries of the human race". It was a very physically demanding job for workers, where the slave workers were considered little different from animals, the miseries of which were depicted in iconography and Apuleius ' The Golden Ass . The peak of Roman technology

1925-438: The bran and germ from the endosperm . The endosperm is ground to create white flour, which may be recombined with the bran and germ to create whole grain or graham flour . The different milling techniques produce visibly different results, but can be made to produce nutritionally and functionally equivalent output. Stone-ground flour is preferred by many bakers and natural food advocates because of its texture, nutty flavour, and

2002-544: The copper mines at Rio Tinto in Spain , one system involving 16 such wheels stacked above one another so as to lift water about 80 feet from the mine sump. Part of such a wheel was found at Dolaucothi , a Roman gold mine in south Wales in the 1930s when the mine was briefly re-opened. It was found about 160 feet below the surface, so must have been part of a similar sequence as that discovered at Rio Tinto. It has recently been carbon dated to about 90 AD, and since

2079-414: The mining industry in order to power various means of ore conveyance. By changing the direction of the wheel, barrels or baskets of ore could be lifted up or lowered down a shaft or inclined plane. There was usually a cable drum or a chain basket on the axle of the wheel. It is essential that the wheel have braking equipment to be able to stop the wheel (known as a braking wheel). The oldest known drawing of

2156-413: The sack floor at the top of the mill on the hoist . The sacks are then emptied into bins, where the grain falls down through a hopper to the millstones on the stone floor below. The flow of grain is regulated by shaking it in a gently sloping trough (the slipper ) from which it falls into a hole in the center of the runner stone. The milled grain (flour) is collected as it emerges through the grooves in

2233-488: The " Norse wheel ", as many were found in Scandinavia. The paddle wheel was attached to a shaft which was, in turn, attached to the centre of the millstone called the "runner stone". The turning force produced by the water on the paddles was transferred directly to the runner stone, causing it to grind against a stationary " bed ", a stone of a similar size and shape. This simple arrangement required no gears , but had

2310-543: The 3rd century AD onwards, and then the widespread expansion of large-scale factory milling installations across the Islamic world from the 8th century onwards. Geared gristmills were built in the medieval Near East and North Africa , which were used for grinding grain and other seeds to produce meals . Gristmills in the Islamic world were powered by both water and wind. The first wind-powered gristmills were built in

2387-592: The 9th and 10th centuries in what are now Afghanistan, Pakistan and Iran. The Egyptian town of Bilbays had a grain-processing factory that produced an estimated 300 tons of flour and grain per day. From the late 10th century onwards, there was an expansion of grist-milling in Northern Europe. In England, the Domesday survey of 1086 gives a precise count of England's water-powered flour mills: there were 5,624, or about one for every 300 inhabitants, and this

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2464-605: The Appalachian Trail or Appalachian Trail Community. Each year's honorees are honored at a Hall of Fame Banquet or Induction. The Museum has established a Hall of Fame Room in the Ironmaster's Mansion Hostel to commemorate the Hall Inductees. The Museum has established a Hall of Fame Room in the Ironmaster's Mansion to honor the Hall of Fame Inductees. The Room includes commemorative plaques for each Class and

2541-469: The advantage that the bottom of the wheel is moving in the same direction as the water in the tailrace which makes it more efficient. It also performs better than an overshot wheel in flood conditions when the water level may submerge the bottom of the wheel. It will continue to rotate until the water in the wheel pit rises quite high on the wheel. This makes the technique particularly suitable for streams that experience significant variations in flow and reduces

2618-901: The belief that it is nutritionally superior and has a better baking quality than steel-roller-milled flour. It is claimed that, as the stones grind relatively slowly, the wheat germ is not exposed to the sort of excessive temperatures that could cause the fat from the germ portion to oxidize and become rancid, which would destroy some of the vitamin content. Stone-milled flour has been found to be relatively high in thiamin, compared to roller-milled flour, especially when milled from hard wheat. Gristmills only grind "clean" grains from which stalks and chaff have previously been removed, but historically some mills also housed equipment for threshing , sorting, and cleaning prior to grinding. Modern mills are usually "merchant mills" that are either privately owned and accept money or trade for milling grains or are owned by corporations that buy unmilled grain and then own

2695-442: The bottom of a water-filled, circular shaft. The water from the mill-race which entered tangentially the pit created a swirling water column that made the fully submerged wheel act like true water turbines , the earliest known to date. Apart from its use in milling and water-raising, ancient engineers applied the paddled waterwheel for automatons and in navigation. Vitruvius (X 9.5–7) describes multi-geared paddle wheels working as

2772-400: The combination of the separate Greek inventions of the toothed gear and the waterwheel into one effective mechanical system for harnessing water power. Vitruvius' waterwheel is described as being immersed with its lower end in the watercourse so that its paddles could be driven by the velocity of the running water (X, 5.2). About the same time, the overshot wheel appears for the first time in

2849-411: The descendants of the water wheel, as they too take advantage of the movement of water downhill. Water wheels come in two basic designs: The latter can be subdivided according to where the water hits the wheel into backshot (pitch-back ), overshot, breastshot, undershot, and stream-wheels. The term undershot can refer to any wheel where the water passes under the wheel but it usually implies that

2926-436: The disadvantage that the speed of rotation of the stone was dependent on the volume and flow of water available and was, therefore, only suitable for use in mountainous regions with fast-flowing streams. This dependence on the volume and speed of flow of the water also meant that the speed of rotation of the stone was highly variable and the optimum grinding speed could not always be maintained. Vertical wheels were in use in

3003-654: The end of the eighteenth century when he automated the process of making flour. His inventions included the Elevator, wood or tin buckets on a vertical endless leather belt, used to move grain and flour vertically upward; the Conveyor, a wooden auger to move material horizontally; the Hopper Boy, a device for stirring and cooling the newly ground flour; the Drill, a horizontal elevator with flaps instead of buckets (similar to

3080-443: The energy in the flow of water striking the wheel as measured by English civil engineer John Smeaton in the 18th century. More modern wheels have higher efficiencies. Stream wheels gain little or no advantage from the head, a difference in water level. Stream wheels mounted on floating platforms are often referred to as hip wheels and the mill as a ship mill . They were sometimes mounted immediately downstream from bridges where

3157-416: The exhausting labor of milling and grinding. The compartmented water wheel comes in two basic forms, the wheel with compartmented body ( Latin tympanum ) and the wheel with compartmented rim or a rim with separate, attached containers. The wheels could be either turned by men treading on its outside or by animals by means of a sakia gear. While the tympanum had a large discharge capacity, it could lift

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3234-506: The flour produced. One common pest found in flour mills is the Mediterranean flour moth . Moth larvae produce a web-like material that clogs machinery, sometimes causing grain mills to shut down. Norse wheel A water wheel is a machine for converting the energy of flowing or falling water into useful forms of power, often in a watermill . A water wheel consists of a wheel (usually constructed from wood or metal), with

3311-431: The flow restriction of the bridge piers increased the speed of the current. Historically they were very inefficient but major advances were made in the eighteenth century. An undershot wheel is a vertically mounted water wheel with a horizontal axle that is rotated by the water from a low weir striking the wheel in the bottom quarter. Most of the energy gain is from the movement of the water and comparatively little from

3388-426: The grinding mechanism or the building that holds it. Grist is grain that has been separated from its chaff in preparation for grinding . The Greek geographer Strabo reports in his Geography a water-powered grain-mill to have existed near the palace of king Mithradates VI Eupator at Cabira , Asia Minor , before 71 BC. The early mills had horizontal paddle wheels, an arrangement which later became known as

3465-420: The head. They are similar in operation and design to stream wheels. The term undershot is sometimes used with related but different meanings: This is the oldest type of vertical water wheel. The word breastshot is used in a variety of ways. Some authors restrict the term to wheels where the water enters at about the 10 o’clock position, others 9 o’clock, and others for a range of heights. In this article it

3542-422: The industrial revolution. A vertically mounted water wheel that is rotated by water entering buckets just past the top of the wheel is said to be overshot. The term is sometimes, erroneously, applied to backshot wheels, where the water goes down behind the wheel. A typical overshot wheel has the water channeled to the wheel at the top and slightly beyond the axle. The water collects in the buckets on that side of

3619-623: The kinetic energy of the water entering the wheel. They are suited to larger heads than the other type of wheel so they are ideally suited to hilly countries. However even the largest water wheel, the Laxey Wheel in the Isle of Man , only utilises a head of around 30 m (100 ft). The world's largest head turbines, Bieudron Hydroelectric Power Station in Switzerland , utilise about 1,869 m (6,132 ft). Overshot wheels require

3696-613: The late Warring States period (476-221 BC). It says that the waterwheel was invented by Zigong, a disciple of Confucius in the 5th century BC. By at least the 1st century AD, the Chinese of the Eastern Han Dynasty were using water wheels to crush grain in mills and to power the piston- bellows in forging iron ore into cast iron . In the text known as the Xin Lun written by Huan Tan about 20 AD (during

3773-475: The metropolis of Alexandria. The earliest depiction of a compartmented wheel is from a tomb painting in Ptolemaic Egypt which dates to the 2nd century BC. It shows a pair of yoked oxen driving the wheel via a sakia gear, which is here for the first time attested, too. The Greek sakia gear system is already shown fully developed to the point that "modern Egyptian devices are virtually identical". It

3850-496: The old wheel mills. In most wheel-driven mills, a large gear-wheel called the pit wheel is mounted on the same axle as the water wheel and this drives a smaller gear-wheel, the wallower , on a main driveshaft running vertically from the bottom to the top of the building. This system of gearing ensures that the main shaft turns faster than the water wheel, which typically rotates at around 10 rpm . The millstones themselves turn at around 120 rpm . They are laid one on top of

3927-414: The other. The bottom stone, called the bed , is fixed to the floor, while the top stone, the runner , is mounted on a separate spindle, driven by the main shaft. A wheel called the stone nut connects the runner's spindle to the main shaft, and this can be moved out of the way to disconnect the stone and stop it turning, leaving the main shaft turning to drive other machinery. This might include driving

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4004-493: The outside of an open-framed wheel. The Romans used waterwheels extensively in mining projects, with enormous Roman-era waterwheels found in places like modern-day Spain . They were reverse overshot water-wheels designed for dewatering deep underground mines. Several such devices are described by Vitruvius , including the reverse overshot water-wheel and the Archimedean screw . Many were found during modern mining at

4081-475: The palace of the Pontian king Mithradates VI Eupator , but its exact construction cannot be gleaned from the text (XII, 3, 30 C 556). The first clear description of a geared watermill offers the late 1st century BC Roman architect Vitruvius who tells of the sakia gearing system as being applied to a watermill. Vitruvius's account is particularly valuable in that it shows how the watermill came about, namely by

4158-418: The pestle and mortar, which is so useful, and later on it was cleverly improved in such a way that the whole weight of the body could be used for treading on the tilt-hammer ( tui ), thus increasing the efficiency ten times. Afterwards the power of animals—donkeys, mules, oxen, and horses—was applied by means of machinery, and water-power too used for pounding, so that the benefit was increased a hundredfold. In

4235-418: The process. Evans himself did not use the term gristmill to describe his automatic flour mill, which was purpose designed as a merchant mill (he used the more general term "water-mill"). In his book his only reference to "grist" (or "grists") is to the small batches of grain a farmer would bring in to have ground for himself (what would be generally called barter or custom milling). In his book, Evans describes

4312-416: The runner stone from the outer rim of the stones and is fed down a chute to be collected in sacks on the ground or meal floor. A similar process is used for grains such as wheat to make flour, and for maize to make corn meal . In order to prevent vibrations from the millstones shaking the building apart, they were usually placed on a separate timber foundation, not attached to the mill walls, known as

4389-497: The rushing of the water ( chi shui ) to operate it ... Thus the people got great benefit for little labor. They found the 'water(-powered) bellows' convenient and adopted it widely. Water wheels in China found practical uses such as this, as well as extraordinary use. The Chinese inventor Zhang Heng (78–139) was the first in history to apply motive power in rotating the astronomical instrument of an armillary sphere , by use of

4466-478: The size, complexity, and hence cost of the tailrace. The direction of rotation of a backshot wheel is the same as that of a breastshot wheel but in other respects, it is very similar to the overshot wheel. See below. Some wheels are overshot at the top and backshot at the bottom thereby potentially combining the best features of both types. The photograph shows an example at Finch Foundry in Devon, UK. The head race

4543-419: The smaller, less expensive and more efficient turbine , developed by Benoît Fourneyron , beginning with his first model in 1827. Turbines are capable of handling high heads , or elevations , that exceed the capability of practical-sized waterwheels. The main difficulty of water wheels is their dependence on flowing water, which limits where they can be located. Modern hydroelectric dams can be viewed as

4620-605: The use of a conveyor but easier to build); and the Descender, an endless strap (leather or flannel) in a trough that is angled downward, the strap helps to move the ground flour in the trough. Most importantly, he integrated these into a single continuous process, the overall design later becoming known as the Automatic (or Automated) mill. In 1790 he received the third Federal patent for his process. In 1795 he published "The Young Mill-Wright and Miller’s Guide" which fully described

4697-457: The use of such wheels for submerging siege mines as a defensive measure against enemy sapping. Compartmented wheels appear to have been the means of choice for draining dry docks in Alexandria under the reign of Ptolemy IV (221−205 BC). Several Greek papyri of the 3rd to 2nd century BC mention the use of these wheels, but do not give further details. The non-existence of the device in

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4774-444: The usurpation of Wang Mang ), it states that the legendary mythological king known as Fu Xi was the one responsible for the pestle and mortar, which evolved into the tilt-hammer and then trip hammer device (see trip hammer ). Although the author speaks of the mythological Fu Xi, a passage of his writing gives hint that the water wheel was in widespread use by the 1st century AD in China ( Wade-Giles spelling): Fu Hsi invented

4851-448: The vertical-axle waterwheel. In the 2nd century AD Barbegal watermill complex a series of sixteen overshot wheels was fed by an artificial aqueduct, a proto-industrial grain factory which has been referred to as "the greatest known concentration of mechanical power in the ancient world". In Roman North Africa , several installations from around 300 AD were found where vertical-axle waterwheels fitted with angled blades were installed at

4928-400: The water entry is low on the wheel. Overshot and backshot water wheels are typically used where the available height difference is more than a couple of meters. Breastshot wheels are more suited to large flows with a moderate head . Undershot and stream wheel use large flows at little or no head. There is often an associated millpond , a reservoir for storing water and hence energy until it

5005-416: The water hits the wheel paddles, into overshot, breastshot and undershot wheels. The two main functions of waterwheels were historically water-lifting for irrigation purposes and milling, particularly of grain. In case of horizontal-axle mills, a system of gears is required for power transmission, which vertical-axle mills do not need. The earliest waterwheel working like a lever was described by Zhuangzi in

5082-434: The water is not constrained by millraces or wheel pits. Stream wheels are cheaper and simpler to build and have less of an environmental impact than other types of wheels. They do not constitute a major change of the river. Their disadvantages are their low efficiency, which means that they generate less power and can only be used where the flow rate is sufficient. A typical flat board undershot wheel uses about 20 percent of

5159-560: The water only to less than the height of its own radius and required a large torque for rotating. These constructional deficiencies were overcome by the wheel with a compartmented rim which was a less heavy design with a higher lift. The earliest literary reference to a water-driven, compartmented wheel appears in the technical treatise Pneumatica (chap. 61) of the Greek engineer Philo of Byzantium ( c.  280  – c.  220 BC ). In his Parasceuastica (91.43−44), Philo advises

5236-561: The wheel and the apron and potentially causing serious damage. Breastshot wheels are less efficient than overshot and backshot wheels but they can handle high flow rates and consequently high power. They are preferred for steady, high-volume flows such as are found on the Fall Line of the North American East Coast. Breastshot wheels are the most common type in the United States of America and are said to have powered

5313-406: The wheel, making it heavier than the other "empty" side. The weight turns the wheel, and the water flows out into the tail-water when the wheel rotates enough to invert the buckets. The overshot design is very efficient, it can achieve 90%, and does not require rapid flow. Nearly all of the energy is gained from the weight of water lowered to the tailrace although a small contribution may be made by

5390-449: The wood from which it was made is much older than the deep mine, it is likely that the deep workings were in operation perhaps 30–50 years after. It is clear from these examples of drainage wheels found in sealed underground galleries in widely separated locations that building water wheels was well within their capabilities, and such verticals water wheels commonly used for industrial purposes. Taking indirect evidence into account from

5467-510: The work of the Greek technician Apollonius of Perge , the British historian of technology M.J.T. Lewis dates the appearance of the vertical-axle watermill to the early 3rd century BC, and the horizontal-axle watermill to around 240 BC, with Byzantium and Alexandria as the assigned places of invention. A watermill is reported by the Greek geographer Strabon ( c.  64 BC  – c.  AD 24 ) to have existed sometime before 71 BC in

5544-589: The year 31 AD, the engineer and Prefect of Nanyang , Du Shi (d. 38), applied a complex use of the water wheel and machinery to power the bellows of the blast furnace to create cast iron . Du Shi is mentioned briefly in the Book of Later Han ( Hou Han Shu ) as follows (in Wade-Giles spelling): In the seventh year of the Chien-Wu reign period (31 AD) Tu Shih was posted to be Prefect of Nanyang. He

5621-458: Was Jim & Molly Denton, JoAnn & Paul Dolan, Laurie Potteiger and Tom Speaks. The 2023 class included M.J. Eberhart, Lester Kenway, Brian B. King and Harry Rentschler. The 2024 class is Edward B. Ballard, Arno Cammerer, Raymond Hunt and Ronald S. Rosen. Gristmill A gristmill (also: grist mill , corn mill , flour mill , feed mill or feedmill ) grinds cereal grain into flour and middlings . The term can refer to either

5698-700: Was Maurice Forrester, Horace Kephart , Larry Luxenberg and Henry "Arch" Nichols. The 2017 class included Harlean James , Charles Parry, Mildred Norman "Peace Pilgrim" Ryder and Matilda "Tillie" Wood. The 2018 class included William "Bill" Kemsley, Jr., Elizabeth Levers, George Masa and Robert "Bob" Peoples. The 2019 class included M. Jean Van Gilder Cashin, Paul M. Fink, Donald T. King and Robert T. Proudman. The 2020 class consisted of Chris Brunton, Warren Doyle , Thurston Griggs and Walkin' Jim Stoltz. The 2021 class included Harvey Benjamin Broome , Stephen Clark, Thomas Johnson and Marianne Skeen. The 2022 class

5775-425: Was a generous man and his policies were peaceful; he destroyed evil-doers and established the dignity (of his office). Good at planning, he loved the common people and wished to save their labor. He invented a water-power reciprocator ( shui phai ) for the casting of (iron) agricultural implements. Those who smelted and cast already had the push-bellows to blow up their charcoal fires, and now they were instructed to use

5852-522: Was a staple part of the diet. Classical mill designs are usually water-powered , though some are powered by the wind or by livestock. In a watermill a sluice gate is opened to allow water to flow onto, or under, a water wheel to make it turn. In most watermills the water wheel was mounted vertically, i.e., edge-on, in the water, but in some cases horizontally (the tub wheel and so-called Norse wheel ). Later designs incorporated horizontal steel or cast iron turbines and these were sometimes refitted into

5929-527: Was probably typical throughout western and southern Europe. From this time onward, water wheels began to be used for purposes other than grist milling. In England, the number of mills in operation followed population growth, and peaked at around 17,000 by 1300. Limited extant examples of gristmills can be found in Europe from the High Middle Ages . An extant well-preserved waterwheel and gristmill on

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