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69-488: Healy Hall serves as the main administrative and reception venue of Georgetown, with some portions still being used as classrooms. The building includes Riggs Library, one of the few extant cast iron libraries in the nation, as well as the elaborate Gaston Hall . In 1873, Patrick Francis Healy became the president of Georgetown University . Soon after entering office, he articulated to the Superior General of

138-751: A cupola , but in modern applications, it is more often melted in electric induction furnaces or electric arc furnaces. After melting is complete, the molten cast iron is poured into a holding furnace or ladle. Cast iron's properties are changed by adding various alloying elements, or alloyants . Next to carbon , silicon is the most important alloyant because it forces carbon out of solution. A low percentage of silicon allows carbon to remain in solution, forming iron carbide and producing white cast iron. A high percentage of silicon forces carbon out of solution, forming graphite and producing grey cast iron. Other alloying agents, manganese , chromium , molybdenum , titanium , and vanadium counteract silicon, and promote

207-464: A 10-tonne impeller) to be sand cast, as the chromium reduces cooling rate required to produce carbides through the greater thicknesses of material. Chromium also produces carbides with impressive abrasion resistance. These high-chromium alloys attribute their superior hardness to the presence of chromium carbides. The main form of these carbides are the eutectic or primary M 7 C 3 carbides, where "M" represents iron or chromium and can vary depending on

276-631: A passing crack and initiate countless new cracks as the material breaks, and ductile cast iron has spherical graphite "nodules" which stop the crack from further progressing. Carbon (C), ranging from 1.8 to 4 wt%, and silicon (Si), 1–3 wt%, are the main alloying elements of cast iron. Iron alloys with lower carbon content are known as steel . Cast iron tends to be brittle , except for malleable cast irons . With its relatively low melting point, good fluidity, castability , excellent machinability , resistance to deformation and wear resistance , cast irons have become an engineering material with

345-563: A rule of mixtures. In any case, they offer hardness at the expense of toughness . Since carbide makes up a large fraction of the material, white cast iron could reasonably be classified as a cermet . White iron is too brittle for use in many structural components, but with good hardness and abrasion resistance and relatively low cost, it finds use in such applications as the wear surfaces ( impeller and volute ) of slurry pumps , shell liners and lifter bars in ball mills and autogenous grinding mills , balls and rings in coal pulverisers . It

414-424: A spongy steel without the stress concentration effects that flakes of graphite would produce. The carbon percentage present is 3-4% and percentage of silicon is 1.8-2.8%.Tiny amounts of 0.02 to 0.1% magnesium , and only 0.02 to 0.04% cerium added to these alloys slow the growth of graphite precipitates by bonding to the edges of the graphite planes. Along with careful control of other elements and timing, this allows

483-417: A wide range of applications and are used in pipes , machines and automotive industry parts, such as cylinder heads , cylinder blocks and gearbox cases. Some alloys are resistant to damage by oxidation . In general, cast iron is notoriously difficult to weld . The earliest cast-iron artefacts date to the 5th century BC, and were discovered by archaeologists in what is now Jiangsu , China. Cast iron

552-399: A year after it was opened. The Dee bridge disaster was caused by excessive loading at the centre of the beam by a passing train, and many similar bridges had to be demolished and rebuilt, often in wrought iron . The bridge had been badly designed, being trussed with wrought iron straps, which were wrongly thought to reinforce the structure. The centres of the beams were put into bending, with

621-659: Is a contributing property of the Georgetown Historic District , which was listed as a National Historic Landmark District on May 28, 1967. The building was brought to national attention in 1973 when it acted as a prominent background for the film The Exorcist . In 1990 the interior hall and also the second story of the building featured in The Exorcist III . The architecture of Healy Hall has been described as both Neo-Romanesque and High Victorian Gothic in style. Of this latter style, it

690-462: Is a class of iron – carbon alloys with a carbon content of more than 2% and silicon content around 1–3%. Its usefulness derives from its relatively low melting temperature. The alloying elements determine the form in which its carbon appears: white cast iron has its carbon combined into an iron carbide named cementite , which is very hard, but brittle, as it allows cracks to pass straight through; grey cast iron has graphite flakes which deflect

759-631: Is a register of historic places in Washington, D.C. that are designated by the District of Columbia Historic Preservation Review Board (HPRB), a component of the District of Columbia Government . The District of Columbia Historic Preservation Review Board (HPRB) designates historic structures and districts and advises the Mayor of the District of Columbia on historic preservation matters. Members of

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828-438: Is added in the ladle or in the furnace, on the order of 0.5–2.5%, to decrease chill, refine graphite, and increase fluidity. Molybdenum is added on the order of 0.3–1% to increase chill and refine the graphite and pearlite structure; it is often added in conjunction with nickel, copper, and chromium to form high strength irons. Titanium is added as a degasser and deoxidizer, but it also increases fluidity. Vanadium at 0.15–0.5%

897-439: Is added to cast iron to stabilize cementite, increase hardness, and increase resistance to wear and heat. Zirconium at 0.1–0.3% helps to form graphite, deoxidize, and increase fluidity. In malleable iron melts, bismuth is added at 0.002–0.01% to increase how much silicon can be added. In white iron, boron is added to aid in the production of malleable iron; it also reduces the coarsening effect of bismuth. Grey cast iron

966-420: Is characterised by its graphitic microstructure, which causes fractures of the material to have a grey appearance. It is the most commonly used cast iron and the most widely used cast material based on weight. Most cast irons have a chemical composition of 2.5–4.0% carbon, 1–3% silicon, and the remainder iron. Grey cast iron has less tensile strength and shock resistance than steel, but its compressive strength

1035-485: Is comparable to low- and medium-carbon steel. These mechanical properties are controlled by the size and shape of the graphite flakes present in the microstructure and can be characterised according to the guidelines given by the ASTM . White cast iron displays white fractured surfaces due to the presence of an iron carbide precipitate called cementite. With a lower silicon content (graphitizing agent) and faster cooling rate,

1104-782: Is considered one of the last large scale examples in the United States. Built in a Neo-Medieval style that combines elements of Romanesque , Early Gothic, Late Gothic and Early Renaissance, the building contains the Office of the President; Georgetown's Department of Classics ; the Kennedy Institute of Ethics ; and the Bioethics Research Library . Notable rooms in Healy include Riggs Library, one of

1173-453: Is difficult to cool thick castings fast enough to solidify the melt as white cast iron all the way through. However, rapid cooling can be used to solidify a shell of white cast iron, after which the remainder cools more slowly to form a core of grey cast iron. The resulting casting, called a chilled casting , has the benefits of a hard surface with a somewhat tougher interior. High-chromium white iron alloys allow massive castings (for example,

1242-605: Is known as the Iron Bridge in Shropshire , England. Cast iron was also used in the construction of buildings . Cast iron is made from pig iron , which is the product of melting iron ore in a blast furnace . Cast iron can be made directly from the molten pig iron or by re-melting pig iron, often along with substantial quantities of iron, steel, limestone, carbon (coke) and taking various steps to remove undesirable contaminants. Phosphorus and sulfur may be burnt out of

1311-433: Is one of the most common alloying elements, because it refines the pearlite and graphite structures, improves toughness, and evens out hardness differences between section thicknesses. Chromium is added in small amounts to reduce free graphite, produce chill, and because it is a powerful carbide stabilizer; nickel is often added in conjunction. A small amount of tin can be added as a substitute for 0.5% chromium. Copper

1380-698: The Chirk Aqueduct and the Pontcysyllte Aqueduct , both of which remain in use following the recent restorations. The best way of using cast iron for bridge construction was by using arches , so that all the material is in compression. Cast iron, again like masonry, is very strong in compression. Wrought iron, like most other kinds of iron and indeed like most metals in general, is strong in tension, and also tough – resistant to fracturing. The relationship between wrought iron and cast iron, for structural purposes, may be thought of as analogous to

1449-527: The Congo region of the Central African forest, blacksmiths invented sophisticated furnaces capable of high temperatures over 1000 years ago. There are countless examples of welding, soldering, and cast iron created in crucibles and poured into molds. These techniques were employed for the use of composite tools and weapons with cast iron or steel blades and soft, flexible wrought iron interiors. Iron wire

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1518-461: The Jesuit order , Peter Jan Beckx , his vision of transforming Georgetown from a college into a true university . This coincided with prominent Catholics calling for the creation of a great Catholic university in the United States, on par with other large American universities established around this time. Healy's transformation involved broadening the school's curriculum and raising the standards of

1587-625: The Law School and School of Medicine . Both Healy and the provincial superior of the Jesuits ' Maryland Province , Joseph Keller, agreed in 1874 that the school's most pressing need was to expand its physical facilities. The two planned for the construction of several new buildings, which would contain classrooms, laboratories , a library, a chapel , and a dormitory for the older students. However, Beckx withheld approval of any new construction until Healy could demonstrate that Georgetown had

1656-531: The Library of Congress Building . Smithmeyer, who was the chief architect, designed the plan and elevations of the structure, while Pelz designed its porches and interior rooms, including Gaston Hall, Riggs Library, and the parlors. Healy chose a site located between Old North and the Preparatory Building, now known as Maguire Hall. This was the first building on Georgetown's campus that would face

1725-542: The Warring States period . This is based on an analysis of the artifact's microstructures. Because cast iron is comparatively brittle, it is not suitable for purposes where a sharp edge or flexibility is required. It is strong under compression, but not under tension. Cast iron was invented in China in the 5th century BC and poured into molds to make ploughshares and pots as well as weapons and pagodas. Although steel

1794-403: The surface tension to form the graphite into spheroidal particles rather than flakes. Due to their lower aspect ratio , the spheroids are relatively short and far from one another, and have a lower cross section vis-a-vis a propagating crack or phonon . They also have blunt boundaries, as opposed to flakes, which alleviates the stress concentration problems found in grey cast iron. In general,

1863-707: The 13th century and other travellers subsequently noted an iron industry in the Alburz Mountains to the south of the Caspian Sea . This is close to the silk route , thus the use of cast-iron technology being derived from China is conceivable. Upon its introduction to the West in the 15th century it was used for cannon and shot . Henry VIII (reigned 1509–1547) initiated the casting of cannon in England. Soon, English iron workers using blast furnaces developed

1932-533: The 1720s and 1730s by a small number of other coke -fired blast furnaces. Application of the steam engine to power blast bellows (indirectly by pumping water to a waterwheel) in Britain, beginning in 1743 and increasing in the 1750s, was a key factor in increasing the production of cast iron, which surged in the following decades. In addition to overcoming the limitation on water power, the steam-pumped-water powered blast gave higher furnace temperatures which allowed

2001-685: The Carroll Parlor and on the ceiling of the Bioethics Reference Center's Hirst Reading Room. Healy Hall rises to a height of 200 feet (61 m), making it the tied with 700 Eleventh Street as the sixth tallest building in Washington, D.C. The hands of the Healy Clock Tower have been subjected to many thefts, as per the university tradition. Historically, students would steal the hands and mail them to

2070-482: The Crown", the 750-seat auditorium which has played host to multitudes of world leaders. Gaston Hall, located on the third and fourth floors and named for Georgetown's first student, William Gaston , is decorated with the coats of arms of the Jesuit colleges and universities and rich allegorical scenes painted by notable Jesuit artist Brother Francis C. Schroen . Schroen also created the intricate paintings found in

2139-577: The D.C. Municipal Regulations at DCMR 10-C, Section C-201. Designated properties must: Properties are eligible for designation as historic landmarks or historic districts if they possess one or more of the following values or qualities: (a) Events: They are the site of events that contributed significantly to the heritage, culture or development of the District of Columbia or the nation; (b) History: They are associated with historical periods, social movements, groups, institutions, achievements, or patterns of growth and change that contributed significantly to

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2208-716: The HPRB are appointed by the mayor and are approved by the Council of the District of Columbia . The D.C. Inventory of Historic Sites was created in 1964, and was originally compiled by the predecessor to the HPRB, the Joint Committee on Landmarks of the National Capital. As of 2019 , the Inventory includes approximately 750 historic sites and 50 historic districts . The criteria for designation are defined by

2277-473: The Industrial Revolution, cast iron was also widely used for frame and other fixed parts of machinery, including spinning and later weaving machines in textile mills. Cast iron became widely used, and many towns had foundries producing industrial and agricultural machinery. District of Columbia Inventory of Historic Sites The District of Columbia Inventory of Historic Sites

2346-618: The Superior General in Rome for approval in January 1877. They called for a building measuring 312 feet (95 m) in length and 95 feet (29 m) in width. Beckx considered the planned building too large and ornate, and thought the projected cost was an underestimate. Nonetheless, he approved the project that year, on the condition that total expenses not exceed $ 100,000, equivalent to $ 2.86 million in 2023. In April 1877, ground

2415-488: The alloy's composition. The eutectic carbides form as bundles of hollow hexagonal rods and grow perpendicular to the hexagonal basal plane. The hardness of these carbides are within the range of 1500-1800HV. Malleable iron starts as a white iron casting that is then heat treated for a day or two at about 950 °C (1,740 °F) and then cooled over a day or two. As a result, the carbon in iron carbide transforms into graphite and ferrite plus carbon. The slow process allows

2484-454: The appearance and development of the District of Columbia or the nation; (e) Artistry: They possess high artistic or aesthetic values that contribute significantly to the heritage and appearance of the District of Columbia or the nation; (f) Work of a Master: They have been identified as notable works of craftsmen, artists, sculptors, architects, landscape architects, urban planners, engineers, builders, or developers whose works have influenced

2553-399: The attics of Healy Hall, crawling through the ducts above Riggs Library to steal the minute hands from both the east and west clock faces. Riggs Library was the main library of Georgetown University from 1891 to 1970, until being replaced by Lauinger Library . It is housed in the south tower of Healy Hall, on the third floor. Riggs Library is one of the few extant cast-iron libraries in

2622-429: The benefit of what is called precipitation hardening (as in some steels, where much smaller cementite precipitates might inhibit [plastic deformation] by impeding the movement of dislocations through the pure iron ferrite matrix). Rather, they increase the bulk hardness of the cast iron simply by virtue of their own very high hardness and their substantial volume fraction, such that the bulk hardness can be approximated by

2691-537: The blast furnaces at Coalbrookdale. Other inventions followed, including one patented by Thomas Paine . Cast-iron bridges became commonplace as the Industrial Revolution gathered pace. Thomas Telford adopted the material for his bridge upstream at Buildwas , and then for Longdon-on-Tern Aqueduct , a canal trough aqueduct at Longdon-on-Tern on the Shrewsbury Canal . It was followed by

2760-539: The bolt holes were also cast and not drilled. Thus, because of casting's draft angle, the tension from the tie bars was placed on the hole's edge rather than being spread over the length of the hole. The replacement bridge was built in wrought iron and steel. Further bridge collapses occurred, however, culminating in the Norwood Junction rail accident of 1891. Thousands of cast-iron rail underbridges were eventually replaced by steel equivalents by 1900 owing to

2829-522: The carbon in white cast iron precipitates out of the melt as the metastable phase cementite , Fe 3 C, rather than graphite. The cementite which precipitates from the melt forms as relatively large particles. As the iron carbide precipitates out, it withdraws carbon from the original melt, moving the mixture toward one that is closer to eutectic , and the remaining phase is the lower iron-carbon austenite (which on cooling might transform to martensite ). These eutectic carbides are much too large to provide

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2898-439: The carbon to separate as spheroidal particles as the material solidifies. The properties are similar to malleable iron, but parts can be cast with larger sections. Cast iron and wrought iron can be produced unintentionally when smelting copper using iron ore as a flux. The earliest cast-iron artifacts date to the 5th century BC, and were discovered by archaeologists in what is now modern Luhe County , Jiangsu in China during

2967-607: The city of Washington , rather than the Potomac River . Plans for the building were first submitted in December 1875. Keller objected to the construction of a single, large building because it would have lacked sufficient dormitory space for the Jesuit scholastics , who he sought to relocate from Woodstock College to Georgetown. However, Keller acquiesced to Healy's plan in May 1876. The designs were tweaked before being sent to

3036-454: The clock hands during his freshman year. On April 1, 1988, Carignan and a fellow student accessed the clock through "a metal plate set into the roof at the base of the clocktower." Eventually tracked down by campus security, Carignan and his Georgetown accomplice were sentenced by a university discipline panel to "an $ 800 fine, a 40-hour work sanction, [and] a year of probation." The writer Joseph Bottum has also published an account of stealing

3105-479: The clock hands. In the Fall of 1977, Bottum joined Stan DeTurris, Dave Barry, and Pat Conway (all freshmen in the class of ’81) to climb through a trap door on the north peak of Healy, above Gaston Hall , and steal the hands from the east face of the clock, returning them at the end of the school year to the university president, Fr. Timothy Healy, S.J. The next year, Bottum writes, he and DeTurris found another way into

3174-627: The cotton, hemp , or wool being spun. As a result, textile mills had an alarming propensity to burn down. The solution was to build them completely of non-combustible materials, and it was found convenient to provide the building with an iron frame, largely of cast iron, replacing flammable wood. The first such building was at Ditherington in Shrewsbury , Shropshire. Many other warehouses were built using cast-iron columns and beams, although faulty designs, flawed beams or overloading sometimes caused building collapses and structural failures. During

3243-536: The development of steel-framed skyscrapers. Cast iron was also used sometimes for decorative facades, especially in the United States, and the Soho district of New York has numerous examples. It was also used occasionally for complete prefabricated buildings, such as the historic Iron Building in Watervliet, New York . Another important use was in textile mills . The air in the mills contained flammable fibres from

3312-520: The effects of sulfur, manganese is added, because the two form into manganese sulfide instead of iron sulfide. The manganese sulfide is lighter than the melt, so it tends to float out of the melt and into the slag . The amount of manganese required to neutralize sulfur is 1.7 × sulfur content + 0.3%. If more than this amount of manganese is added, then manganese carbide forms, which increases hardness and chilling , except in grey iron, where up to 1% of manganese increases strength and density. Nickel

3381-405: The evolution of their fields of endeavor, or are significant to the development of the District of Columbia or the nation; or (g) Archaeology: They have yielded or may be likely to yield information significant to an understanding of historic or prehistoric events, cultures, and standards of living, building, and design. Properties shall possess sufficient integrity to convey, represent or contain

3450-558: The few extant cast iron libraries in the nation; the Philodemic Room, the meeting room for the Philodemic Society , one of the oldest collegiate debating clubs in the nation; the grand Hall of Cardinals; the historic Constitution Room; and the Carroll Parlor, which houses several notable pieces from the university's art collection. Perhaps the grandest space in the building is Gaston Hall , Georgetown's "Jewel in

3519-409: The hands however, as they are captured every five to six years. In May of 1997, three students calling themselves "The Explorers" stole the clocktower hands and later returned them to Georgetown University President Father O'Donovan and sent a letter to The Hoya claiming responsibility for the heist and encouraging future Hoyas to "keep the spirit of pranksterism alive at Georgetown." In the fall of 2005

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3588-529: The hands were stolen by Drew Hamblen (SFS ’07) and Wyatt Gjullin (COL ’09). The hands were stolen once again during the evening between April 29 and April 30, 2012, and supposedly sent to Barack Obama but the hands ended up lost in the mail. More recently, the clock hands were stolen during the evening between December 9th and December 10th, 2014, and again sometime during the night of April 30, 2017. The hands were stolen and subsequently retrieved on May 8, 2023. Dean M. Carignan (SFS '91) has written of his stealing

3657-474: The heritage, culture or development of the District of Columbia or the nation; (c) Individuals: They are associated with the lives of persons significant to the history of the District of Columbia or the nation; (d) Architecture and Urbanism: They embody the distinguishing characteristics of architectural styles, building types, or methods of construction, or are expressions of landscape architecture, engineering, or urban planning, siting, or design significant to

3726-539: The lower edge in tension, where cast iron, like masonry , is very weak. Nevertheless, cast iron continued to be used in inappropriate structural ways, until the Tay Rail Bridge disaster of 1879 cast serious doubt on the use of the material. Crucial lugs for holding tie bars and struts in the Tay Bridge had been cast integral with the columns, and they failed in the early stages of the accident. In addition,

3795-452: The means to finance such a project. As time passed, the initial plan for several new buildings developed into a plan to build one grand building. Healy initially consulted Patrick C. Keely , a church architect from New York , about designing the new building. However, he decided it was better to hire an architect closer to Georgetown, and in fall 1874, he selected John L. Smithmeyer and his associate, Paul J. Pelz , who would later design

3864-406: The molten iron, but this also burns out the carbon, which must be replaced. Depending on the application, carbon and silicon content are adjusted to the desired levels, which may be anywhere from 2–3.5% and 1–3%, respectively. If desired, other elements are then added to the melt before the final form is produced by casting . Cast iron is sometimes melted in a special type of blast furnace known as

3933-440: The nation. The library still serves its original function of storing books despite its primary use as a formal event space. The library's construction was funded by E. Francis Riggs as a memorial to his father and brother, and was supervised by architect Paul Pelz , who designed Healy Hall and the Library of Congress , although Riggs did not open until a full decade after Healy Hall opened for use. Cast iron Cast iron

4002-466: The person they wished to visit the campus, most notably sent to the Vatican , where they were blessed by Pope John Paul II and then returned to the university. One such incident caused significant damage to the clock mechanism, however, and security has been increased as a result in recent years, decreasing the incidence of the theft. These measures have not prevented students from successfully obtaining

4071-418: The properties of malleable cast iron are more like those of mild steel . There is a limit to how large a part can be cast in malleable iron, as it is made from white cast iron. Developed in 1948, nodular or ductile cast iron has its graphite in the form of very tiny nodules with the graphite in the form of concentric layers forming the nodules. As a result, the properties of ductile cast iron are that of

4140-713: The relationship between wood and stone. Cast-iron beam bridges were used widely by the early railways, such as the Water Street Bridge in 1830 at the Manchester terminus of the Liverpool and Manchester Railway , but problems with its use became all too apparent when a new bridge carrying the Chester and Holyhead Railway across the River Dee in Chester collapsed killing five people in May 1847, less than

4209-475: The retention of carbon and the formation of those carbides. Nickel and copper increase strength and machinability, but do not change the amount of graphite formed. Carbon as graphite produces a softer iron, reduces shrinkage, lowers strength, and decreases density. Sulfur , largely a contaminant when present, forms iron sulfide , which prevents the formation of graphite and increases hardness . Sulfur makes molten cast iron viscous, which causes defects. To counter

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4278-501: The technique of producing cast-iron cannons, which, while heavier than the prevailing bronze cannons, were much cheaper and enabled England to arm her navy better. Cast-iron pots were made at many English blast furnaces at the time. In 1707, Abraham Darby patented a new method of making pots (and kettles) thinner and hence cheaper than those made by traditional methods. This meant that his Coalbrookdale furnaces became dominant as suppliers of pots, an activity in which they were joined in

4347-588: The university deeply in debt and in possession for years of an enormous pile of dirt as a result of the excavation, with no funds to remove it. As a result of the debts, the Gaston Hall auditorium could not be completed until 1909. The building was listed on District of Columbia Inventory of Historic Sites in 1964, on the National Register of Historic Places on May 25, 1971, and as a National Historic Landmark on December 23, 1987. In addition, it

4416-566: The use of higher lime ratios, enabling the conversion from charcoal (supplies of wood for which were inadequate) to coke. The ironmasters of the Weald continued producing cast irons until the 1760s, and armament was one of the main uses of irons after the Restoration . The use of cast iron for structural purposes began in the late 1770s, when Abraham Darby III built The Iron Bridge , although short beams had already been used, such as in

4485-518: The widespread concern about cast iron under bridges on the rail network in Britain. Cast-iron columns , pioneered in mill buildings, enabled architects to build multi-storey buildings without the enormously thick walls required for masonry buildings of any height. They also opened up floor spaces in factories, and sight lines in churches and auditoriums. By the mid 19th century, cast iron columns were common in warehouse and industrial buildings, combined with wrought or cast iron beams, eventually leading to

4554-514: Was also produced. Numerous testimonies were made by early European missionaries of the Luba people pouring cast iron into molds to make hoes. These technological innovations were accomplished without the invention of the blast furnace which was the prerequisite for the deployment of such innovations in Europe and Asia. The technology of cast iron was transferred to the West from China. Al-Qazvini in

4623-475: Was broken on the foundation , which was completed in October. The construction of the building, from 1877 to 1879, dramatically increased the amount of classroom and living space—at the time, it was also used as a dormitory—of what was then a small liberal arts college . Prior to its construction, Old North housed most of the college's classrooms, dormitories, and other facilities. The construction also left

4692-410: Was more desirable, cast iron was cheaper and thus was more commonly used for implements in ancient China, while wrought iron or steel was used for weapons. The Chinese developed a method of annealing cast iron by keeping hot castings in an oxidizing atmosphere for a week or longer in order to burn off some carbon near the surface in order to keep the surface layer from being too brittle. Deep within

4761-522: Was used in ancient China to mass-produce weaponry for warfare, as well as agriculture and architecture. During the 15th century AD, cast iron became utilized for cannons and shot in Burgundy , France, and in England during the Reformation . The amounts of cast iron used for cannons required large-scale production. The first cast-iron bridge was built during the 1770s by Abraham Darby III , and

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