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49-470: Jan Adriaenszoon Leeghwater (born Jan Adriaenszoon ; November 1575 – January 1650) was a Dutch millwright and hydraulic engineer . Leeghwater was born as Jan Adriaanszoon. Only later did he adopt the name Leeghwater, from laag water or low water . It is not clear exactly how the prevalent spelling of Leeghwater's name came about. Leeghwater himself spelt his name alternatively as Leegwater, Leegh-water, Leeghwater and Leechwater. Official documents of

98-646: A 4- year apprenticeship before becoming a journeyman. Apprentices are usually paid a percentage of the average millwright's wage, and this percentage increases with experience. A typical training course, to qualify as a millwright, may include, among others, the following: In South Africa, the millwright trade (especially focused on the mining sector) enjoys a far more versatile description than in most other countries. Fields wherein South African millwrights may operate include: At most trades training centers, prospective millwright artisans are required to have

147-447: A certain level of theoretical certification (e.g. N3-Nated- certificate) and psychometric characteristics, judged by thorough testing, in order to qualify for the foundation practical and theoretical technical training. After being trained in a multitude of different fields, novice, unqualified Millwrights enter in an apprenticeship for "on-the-job" training. There they work alongside all available artisans regardless of trade, depending on

196-413: 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

245-412: 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

294-773: A minimum of 1560 hours of on-the-job training and eight weeks of technical training each year. Within the Steelworkers Union, known as the United Steelworkers or USW, the largest Industrial Union in North America, there is also a mix of both classroom and on-the-job training. Upon successful completion of required testing in blueprints, hydraulics, pneumatics, rigging, pipefitting, welding, burning, gears, couplings, and other various types of mechanical fasteners and machinery, as well as mobile equipment and other heavy machinery. A typical millwright serves

343-437: A particular trade. Other countries use different terms to describe tradesmen engaging in similar activities. Related but distinct crafts include machinists , mechanics and mechanical fitters. As the name suggests, the original function of a millwright was the construction of flour mills , sawmills , paper mills and fulling mills powered by water or wind , made mostly of wood with a limited number of metal parts. Since

392-586: 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

441-434: 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

490-898: A typical job millwrights: Modern standards of practice for millwrights also require working: Millwrights by nature of their profession have to be extremely well versed in many aspects of construction/demobilization. They may install a conveyor system at an airport one week and the following week work at an industrial wastewater treatment plant. Millwrights in the power generation industry can assemble, set, align and balance turbines or rotors, as well as install pumps, valves, cranes, fans, and travelling screens. Millwrights also perform critical lifts involving major components to be flown level at up to and within .005 inch (5 thousandths of an inch). Because of their training and expertise, Millwrights are generally chosen to work on tasks associated with flying and setting heavy machinery. Millwrights are also in demand as teachers for vocational programs, both at

539-487: A wide array of precision tools, such as calipers , micrometers, dial indicators, levels, gauge blocks, and optical and laser alignment tooling. Most millwrights are educated through apprenticeship programs where they receive a combination of classroom education along with a good deal of on-the-job training. For example, in Alberta , the term of apprenticeship for a millwright is four years (four 12-month periods) including

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588-498: 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 the " Norse wheel ", as many were found in Scandinavia. The paddle wheel

637-615: 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

686-755: 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

735-438: 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

784-413: 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

833-477: The 1821 book 'Verhandeling over de droogmaking van het Haarlemmermeer' with the 3-way steam pump reclamation plan, and Nicolaas Kruik , who wrote an early "water defence" plan in 1737 using windmills. André Lehr's criticism in the article about the building of clocks and casting bells by Leeghwater emerges that many of the allegations that have been made in later life by Leeghwater, can't be beat. The biographer of Leeghwater, mr. J.G. de Roever wrote that Leeghwaeter

882-486: The 20th century, the trade adapted to the change. Modern millwrights work with steel and other materials and must often combine the skills of other mechanical trades in order to successfully install industrial machinery or to assemble machines from pre-fabricated parts. Modern millwrights must also be able to read blueprints and other schematics to aid them in the construction of complex systems. Millwrights are frequently unionized , with estimated numbers of around 45% in

931-543: 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

980-592: 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

1029-485: The Muslims. They used several solutions to achieve the maximum output from watermills, by either mounting them to piers of bridges to take advantage of the increased flow or by using a shipmill, a type of watermill powered by water wheels mounted on the sides of ships moored in midstream . In Medieval Europe, millwrights built the first industrial mills which introduced new innovative uses of waterpower. A survey of

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1078-466: The US. Millwrights install, maintain, repair and troubleshoot stationary industrial machinery and mechanical equipment in sites such as factories, production plants and recreational facilities. However, the exact duties of a millwright vary depending on whether they are unionized or not, with union rules typically being more restrictive than non-union situations, which may have their own job description . On

1127-794: The Zuidertoren in Amsterdam, he has probably used the older bells by Jacob Waghevens and Adriaan Steylaert which did service before in earlier days in the Oudekerkstoren also in Amsterdam. He reused them and for the Westertoren the bells were possibly cast at the then in Amsterdam working city bell founder Assuerus Koster. By this Koster there are still the hour and half hour strike clocks from 1636 in Amsterdam Westertoren. The clocks and bells that he supplied according to

1176-515: The archives for these towers will not have been of good quality, for less than thirty years later they were replaced by Jurriaan Spraeckel who worked together with François and Pieter Hemony in many places. Today there is no old clock or carillon by Leeghwater recovered. Millwright The term millwright (also known as industrial mechanic ) is mainly used in the United States, Canada and South Africa to describe members belonging to

1225-901: 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

1274-470: The birth of new trades ( turners , fitters , machine makers, and mechanical engineers ). It also changed the traditional job of the millwright. As James F. Hobart wrote in his book Millwrighting , "The ancient type of millwright has passed away. He has gone with the old time carpenter and obsolete shoemaker - the former with 500 pounds of molding planes and woodworking tools, the latter with nothing but pegging and sewing awls, hammer, and knife..." Through

1323-654: 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

1372-401: 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

1421-466: The equipment, which millwrights typically connect with some type of coupling . Originally, millwrights were specialized carpenters who completely designed and constructed mills. Having a working knowledge of drive shafts , bearings , gearing and mechanical belts , they executed every type of engineering operation in the construction of these mills. They designed the patterns of the water wheel systems, carved their gear mechanisms, and finally erected

1470-524: The high school level and in post-secondary institutions. Many high schools feature fabrication courses that include metal work, where the experience of a qualified millwright is valuable. Often, these millwrights are paid a premium based on their years of field experience. Millwrights must have a good understanding of fluid mechanics ( hydraulics and pneumatics ), and all of the components involved in these processes, such as valves , cylinders , pumps and compressors . They are also trained to work with

1519-488: The institution. Once they meet a structured quota of experience and pass the necessary modules, apprentices have two months to prepare for their practical Trade Test. After they passed, they receive the certification and status of a qualified Millwright Tradesman. Once millwrights qualify, they have the opportunity to qualify as technicians, engineers, planners, foremen and many other routes requiring mainly electrical and mechanical expertise. Many millwrights choose to enter

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1568-442: The late centuries was an itinerant engineer and mechanic of high reputation. He could handle the axe, the hammer, and the plane with equal skill and precision...he could set out and cut in the furrows of a millstone with an accuracy equal or superior to that of the miller himself." The introduction of the steam engine and the increasing importance of iron and steel changed the global industrial landscape. It created specialisation and

1617-591: The mill machines. In the Hellenistic period , Greek millwrights invented the two main components of watermills, the waterwheel and toothed gearing. Greeks, along with the Romans , were the first to operate undershot, overshot and breastshot waterwheel mills. Muslim millwrights adopted the Greek watermill technology from the Byzantine Empire , where it had been applied for centuries in those provinces conquered by

1666-532: The milling. Between 1607 and 1635, the polders Purmer , Schermer and Heerhugowaard were also created under his supervision. He was also known for bell casting and clock making in the church towers in Amsterdam. Leeghwater was among the first to advocate reclamation of the Haarlemmermeer , a lake whose growth presented a danger to the surrounding towns (several villages were swallowed and even Amsterdam and Leiden were eventually threatened). When this

1715-496: 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

1764-414: 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

1813-405: The private sector to work on a contractual basis. A number of prominent early-modern civil engineers originally trained as millwrights, including: 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 the grinding mechanism or the building that holds it. Grist

1862-418: 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

1911-416: 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

1960-471: 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 the Roman Empire by

2009-576: The time also mention Laechwater and Laachwater. Leeghwater, as a hydraulic engineer, was pivotal to land reclamation programs along the flooded coast of the Netherlands. He was involved in the reclamation of the Beemster polder , the first polder in the world created from a lake by draining the water using wind mills . The reclamation of the Beemster was started in 1607 and Leeghwater supervised

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2058-446: The types introduced in Western Europe was conducted by Adam Robert Lucas. In China, in the late 14th century, the millwrights were known as jiang and kong (a special term for artisan-engineers) and existed at an early age. They learned their craft on the shop floor, in a kind of apprenticeship scheme. Sir William Fairbairn , a millwright of the late 19th century, wrote in his "Treatise on Mills and Millwork", "...the millwright of

2107-605: 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

2156-463: The use of these structures originates in antiquity, millwrighting could arguably be considered one of the oldest engineering trades and the forerunner of modern mechanical engineering. In modern usage, a millwright is engaged with the erection of machinery. This includes such tasks as leveling, aligning, and installing machinery on foundations or base plates, or setting, leveling, and aligning electric motors or other power sources such as turbines with

2205-522: 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

2254-401: 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 the disadvantage that the speed of rotation of

2303-542: Was finally accomplished in 1852, it was with three large steam-driven pumping installations; one at Lijnden , Kaag , and Cruquius . The installation at Kaag, the Gemaal De Leeghwater  [ nl ] , built with a steam engine in 1845 to pump water into the Kaag lake, was named after him. The other two men honored in this way were Frans Godard baron van Lynden van Hemmen  [ nl ] , who wrote

2352-527: 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

2401-430: Was vain and a braggart. This was written on the basis of archival research. He had much less to do with the reclaimed land than he wanted us to believe. The historiography of the reclaimed land and mill construction was proposed in the 19th century rather romanticized where men apparently was in need of that time. In addition, it is almost certain that he never has cast bells, but left this casting to other bell founders. For

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