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65-543: Friedrich Hoffmann or Hofmann (19 February 1660 – 12 November 1742) was a German physician and chemist . He is also sometimes known in English as Frederick Hoffmann . His family had been connected with medicine for 200 years before him. Born in Halle , he attended the local gymnasium where he acquired that taste for and skill in mathematics to which he attributed much of his later success. Beginning at age 18, he studied medicine at

130-817: A M.S. as professors too (and rarely, some big universities who need part-time or temporary instructors, or temporary staff), but when the positions are scarce and the applicants are many, they might prefer Ph.D. holders instead. Skills that a chemist may need on the job include: Most chemists begin their lives in research laboratories . Many chemists continue working at universities. Other chemists may start companies, teach at high schools or colleges, take samples outside (as environmental chemists ), or work in medical examiner offices or police departments (as forensic chemists ). Some software that chemists may find themselves using include: Increasingly, chemists may also find themselves using artificial intelligence , such as for drug discovery . Chemistry typically

195-403: A Master of Science (M.S.) in chemistry or in a very related discipline may find chemist roles that allow them to enjoy more independence, leadership and responsibility earlier in their careers with less years of experience than those with a bachelor's degree as highest degree. Sometimes, M.S. chemists receive more complex tasks duties in comparison with the roles and positions found by chemists with

260-559: A Ph.D. more often than not. Chemists with a Ph.D. as the highest academic degree are found typically on the research-and-development department of an enterprise and can also hold university positions as professors. Professors for research universities or for big universities usually have a Ph.D., and some research-oriented institutions might require post-doctoral training. Some smaller colleges (including some smaller four-year colleges or smaller non-research universities for undergraduates) as well as community colleges usually hire chemists with

325-604: A bachelor's degree are most commonly involved in positions related to either research assistance (working under the guidance of senior chemists in a research-oriented activity), or, alternatively, they may work on distinct (chemistry-related) aspects of a business, organization or enterprise including aspects that involve quality control, quality assurance, manufacturing, production, formulation, inspection, method validation, visitation for troubleshooting of chemistry-related instruments, regulatory affairs , "on-demand" technical services, chemical analysis for non-research purposes (e.g., as

390-466: A bachelor's degree as their highest academic degree and with the same or close-to-same years of job experience. There are positions that are open only to those that at least have a degree related to chemistry at the master's level. Although good chemists without a Ph.D. degree but with relatively many years of experience may be allowed some applied research positions, the general rule is that Ph.D. chemists are preferred for research positions and are typically

455-507: A burial site located in the western industrial zone of Varna , approximately 4 km from the city centre, internationally considered one of the key archaeological sites in world prehistory. The oldest gold treasure in the world, dating from 4,600 BC to 4,200 BC, was discovered at the site. The gold piece dating from 4,500 BC, found in 2019 in Durankulak , near Varna is another important example. Other signs of early metals are found from

520-435: A combination of education, experience and personal achievements), the higher the responsibility given to that chemist and the more complicated the task might be. Chemistry, as a field, have so many applications that different tasks and objectives can be given to workers or scientists with these different levels of education or experience. The specific title of each job varies from position to position, depending on factors such as

585-410: A complexity requiring an education with a chemistry degree, are commonly referred to as chemical technicians . Such technicians commonly do such work as simpler, routine analyses for quality control or in clinical laboratories , having an associate degree . A chemical technologist has more education or experience than a chemical technician but less than a chemist, often having a bachelor's degree in

650-409: A different field of science with also an associate degree in chemistry (or many credits related to chemistry) or having the same education as a chemical technician but more experience. There are also degrees specific to become a chemical technologist, which are somewhat distinct from those required when a student is interested in becoming a professional chemist. A Chemical technologist is more involved in

715-410: A ductile to brittle transition and lose their toughness, becoming more brittle and prone to cracking. Metals under continual cyclic loading can suffer from metal fatigue . Metals under constant stress at elevated temperatures can creep . Cold-working processes, in which the product's shape is altered by rolling, fabrication or other processes, while the product is cold, can increase the strength of

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780-414: A high position in that town. After practising at Minden for two years, Hoffmann made a journey to Holland and England, where he formed the acquaintance of many illustrious chemists and physicians. Towards the end of 1684, he returned to Minden, and during the next three years he received many flattering appointments. In 1688 he moved to the more promising sphere of Halberstadt , with the title of physician to

845-507: A legal request, for testing purposes, or for government or non-profit agencies); chemists may also work in environmental evaluation and assessment. Other jobs or roles may include sales and marketing of chemical products and chemistry-related instruments or technical writing. The more experience obtained, the more independence and leadership or management roles these chemists may perform in those organizations. Some chemists with relatively higher experience might change jobs or job position to become

910-413: A liquid bath. Metallurgists study the microscopic and macroscopic structure of metals using metallography , a technique invented by Henry Clifton Sorby . In metallography, an alloy of interest is ground flat and polished to a mirror finish. The sample can then be etched to reveal the microstructure and macrostructure of the metal. The sample is then examined in an optical or electron microscope , and

975-401: A major concern. Cast irons, including ductile iron , are also part of the iron-carbon system. Iron-Manganese-Chromium alloys (Hadfield-type steels) are also used in non-magnetic applications such as directional drilling. Other engineering metals include aluminium , chromium , copper , magnesium , nickel , titanium , zinc , and silicon . These metals are most often used as alloys with

1040-468: A manager of a chemistry-related enterprise, a supervisor, an entrepreneur or a chemistry consultant. Other chemists choose to combine their education and experience as a chemist with a distinct credential to provide different services (e.g., forensic chemists, chemistry-related software development, patent law specialists, environmental law firm staff, scientific news reporting staff, engineering design staff, etc.). In comparison, chemists who have obtained

1105-528: A pioneer and chief promoter of their study, gave prescriptions for their use, taught how they could be imitated artificially, and analyzed many German springs. He concluded that solid constituents, such as lime , magnesia , etc., in the form of an alkali and carbonic acid , existed in almost all mineral springs. He wrote on healing springs as early as 1684. Georg Ernst Stahl opposed the general employment of mineral waters recommended by Hoffmann, though he did not question their utility in certain cases. Hoffman

1170-615: A smelted copper axe dating from 5,500 BC, belonging to the Vinča culture . The Balkans and adjacent Carpathian region were the location of major Chalcolithic cultures including Vinča , Varna , Karanovo , Gumelnița and Hamangia , which are often grouped together under the name of ' Old Europe '. With the Carpatho-Balkan region described as the 'earliest metallurgical province in Eurasia', its scale and technical quality of metal production in

1235-563: A superior metal could be made, an alloy called bronze . This represented a major technological shift known as the Bronze Age . The extraction of iron from its ore into a workable metal is much more difficult than for copper or tin. The process appears to have been invented by the Hittites in about 1200 BC, beginning the Iron Age . The secret of extracting and working iron was a key factor in

1300-401: Is a chemical surface-treatment technique. It involves bonding a thin layer of another metal such as gold , silver , chromium or zinc to the surface of the product. This is done by selecting the coating material electrolyte solution, which is the material that is going to coat the workpiece (gold, silver, zinc). There needs to be two electrodes of different materials: one the same material as

1365-639: Is also known as " the central science ", thus chemists ought to have a well-rounded knowledge about science. At the Master's level and higher, students tend to specialize in a particular field. Fields of specialization include biochemistry , nuclear chemistry , organic chemistry , inorganic chemistry , polymer chemistry , analytical chemistry , physical chemistry , theoretical chemistry , quantum chemistry , environmental chemistry , and thermochemistry . Postdoctoral experience may be required for certain positions. Workers whose work involves chemistry, but not at

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1430-443: Is an industrial coating process that consists of a heat source (flame or other) and a coating material that can be in a powder or wire form, which is melted then sprayed on the surface of the material being treated at a high velocity. The spray treating process is known by many different names such as HVOF (High Velocity Oxygen Fuel), plasma spray, flame spray, arc spray and metalizing. Electroless deposition (ED) or electroless plating

1495-708: Is collected and processed to extract valuable metals. Ore bodies often contain more than one valuable metal. Tailings of a previous process may be used as a feed in another process to extract a secondary product from the original ore. Additionally, a concentrate may contain more than one valuable metal. That concentrate would then be processed to separate the valuable metals into individual constituents. Much effort has been placed on understanding iron –carbon alloy system, which includes steels and cast irons . Plain carbon steels (those that contain essentially only carbon as an alloying element) are used in low-cost, high-strength applications, where neither weight nor corrosion are

1560-615: Is credited with conducting the first scientific investigation into carbon monoxide poisoning caused by burning charcoal . He rejected superstition that had attributed the death of several treasure seekers to paranormal activity and published " Considerations on the Fatal Effects of the Vapor from Burning Charcoal" in 1716 which characterized inhalation of polluted air from charcoal vapor causing suffocation similar to strangulation or drowning. Chemist Chemists use their knowledge to learn

1625-455: Is defined as the autocatalytic process through which metals and metal alloys are deposited onto nonconductive surfaces. These nonconductive surfaces include plastics, ceramics, and glass etc., which can then become decorative, anti-corrosive, and conductive depending on their final functions. Electroless deposition is a chemical processes that create metal coatings on various materials by autocatalytic chemical reduction of metal cations in

1690-1094: Is divided into several major sub-disciplines. There are also several main cross-disciplinary and more specialized fields of chemistry. There is a great deal of overlap between different branches of chemistry, as well as with other scientific fields such as biology, medicine, physics, radiology , and several engineering disciplines. All the above major areas of chemistry employ chemists. Other fields where chemical degrees are useful include astrochemistry (and cosmochemistry ), atmospheric chemistry , chemical engineering , chemo-informatics , electrochemistry , environmental science , forensic science , geochemistry , green chemistry , history of chemistry , materials science , medical science , molecular biology , molecular genetics , nanotechnology , nuclear chemistry , oenology , organometallic chemistry , petrochemistry , pharmacology , photochemistry , phytochemistry , polymer chemistry , supramolecular chemistry and surface chemistry . Chemists may belong to professional societies specifically for professionals and researchers within

1755-644: Is found in the Balkans and Carpathian Mountains , as evidenced by findings of objects made by metal casting and smelting dated to around 6000-5000 BC. Certain metals, such as tin, lead, and copper can be recovered from their ores by simply heating the rocks in a fire or blast furnace in a process known as smelting. The first evidence of copper smelting, dating from the 6th millennium BC, has been found at archaeological sites in Majdanpek , Jarmovac and Pločnik , in present-day Serbia . The site of Pločnik has produced

1820-504: Is known as a metallurgist. The science of metallurgy is further subdivided into two broad categories: chemical metallurgy and physical metallurgy . Chemical metallurgy is chiefly concerned with the reduction and oxidation of metals, and the chemical performance of metals. Subjects of study in chemical metallurgy include mineral processing , the extraction of metals , thermodynamics , electrochemistry , and chemical degradation ( corrosion ). In contrast, physical metallurgy focuses on

1885-429: Is often related to the work of chemical engineers , who are primarily concerned with the proper design, construction and evaluation of the most cost-effective large-scale chemical plants and work closely with industrial chemists on the development of new processes and methods for the commercial-scale manufacture of chemicals and related products. The roots of chemistry can be traced to the phenomenon of burning . Fire

1950-530: Is the more common one in the United Kingdom . The / ˈ m ɛ t əl ɜːr dʒ i / pronunciation is the more common one in the United States US and is the first-listed variant in various American dictionaries, including Merriam-Webster Collegiate and American Heritage . The earliest metal employed by humans appears to be gold , which can be found " native ". Small amounts of natural gold, dating to

2015-640: The Neo-Latin noun chimista , an abbreviation of alchimista ( alchemist ). Alchemists discovered many chemical processes that led to the development of modern chemistry. Chemistry as we know it today, was invented by Antoine Lavoisier with his law of conservation of mass in 1783. The discoveries of the chemical elements has a long history culminating in the creation of the periodic table by Dmitri Mendeleev . The Nobel Prize in Chemistry created in 1901 gives an excellent overview of chemical discovery since

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2080-506: The University of Jena . From there, in 1680, he went to Erfurt , to attend Kasper Cramer's lectures on chemistry. Next year, returning to Jena, he received his doctor's diploma, and, after publishing a thesis, was permitted to teach. Constant study then began to tell on his health, and in 1682, leaving his already numerous pupils, he opened a practice in Minden at the request of a relative who held

2145-403: The science and the technology of metals, including the production of metals and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking . Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. A specialist practitioner of metallurgy

2210-570: The 2015 Hague Ethical Guidelines . The highest honor awarded to chemists is the Nobel Prize in Chemistry , awarded since 1901, by the Royal Swedish Academy of Sciences . Metallurgist Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements , their inter-metallic compounds , and their mixtures, which are known as alloys . Metallurgy encompasses both

2275-518: The 6th–5th millennia BC totally overshadowed that of any other contemporary production centre. The earliest documented use of lead (possibly native or smelted) in the Near East dates from the 6th millennium BC, is from the late Neolithic settlements of Yarim Tepe and Arpachiyah in Iraq . The artifacts suggest that lead smelting may have predated copper smelting. Metallurgy of lead has also been found in

2340-642: The Balkans during the same period. Copper smelting is documented at sites in Anatolia and at the site of Tal-i Iblis in southeastern Iran from c. 5000 BC. Copper smelting is first documented in the Delta region of northern Egypt in c. 4000 BC, associated with the Maadi culture . This represents the earliest evidence for smelting in Africa. The Varna Necropolis , Bulgaria , is

2405-416: The coating material and one that is receiving the coating material. Two electrodes are electrically charged and the coating material is stuck to the work piece. It is used to reduce corrosion as well as to improve the product's aesthetic appearance. It is also used to make inexpensive metals look like the more expensive ones (gold, silver). Shot peening is a cold working process used to finish metal parts. In

2470-407: The composition and properties of unfamiliar substances, as well as to reproduce and synthesize large quantities of useful naturally occurring substances and create new artificial substances and useful processes. Chemists may specialize in any number of subdisciplines of chemistry . Materials scientists and metallurgists share much of the same education and skills with chemists. The work of chemists

2535-420: The exact roles of these chemistry-related workers as standard for that given level of education. Because of these factors affecting exact job titles with distinct responsibilities, some chemists might begin doing technician tasks while other chemists might begin doing more complicated tasks than those of a technician, such as tasks that also involve formal applied research, management, or supervision included within

2600-919: The field of chemistry, such as the Royal Society of Chemistry in the United Kingdom, the American Chemical Society (ACS) in the United States, or the Institution of Chemists in India. The "Global Chemists' Code of Ethics" suggests several ethical principles that all chemists should follow: This code of ethics was codified in a 2016 conference held in Kuala Lumpur, Malaysia , run by the American Chemical Society. The points listed are inspired by

2665-619: The highly developed and complex processes of mining metal ores, metal extraction, and metallurgy of the time. Agricola has been described as the "father of metallurgy". Extractive metallurgy is the practice of removing valuable metals from an ore and refining the extracted raw metals into a purer form. In order to convert a metal oxide or sulphide to a purer metal, the ore must be reduced physically, chemically , or electrolytically . Extractive metallurgists are interested in three primary streams: feed, concentrate (metal oxide/sulphide) and tailings (waste). After mining, large pieces of

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2730-402: The image contrast provides details on the composition, mechanical properties, and processing history. Crystallography , often using diffraction of x-rays or electrons , is another valuable tool available to the modern metallurgist. Crystallography allows identification of unknown materials and reveals the crystal structure of the sample. Quantitative crystallography can be used to calculate

2795-501: The joining of metals (including welding , brazing , and soldering ). Emerging areas for metallurgists include nanotechnology , superconductors , composites , biomedical materials , electronic materials (semiconductors) and surface engineering . Metallurgy derives from the Ancient Greek μεταλλουργός , metallourgós , "worker in metal", from μέταλλον , métallon , "mine, metal" + ἔργον , érgon , "work" The word

2860-419: The kind of industry, the routine level of the task, the current needs of a particular enterprise, the size of the enterprise or hiring firm, the philosophy and management principles of the hiring firm, the visibility of the competency and individual achievements of the one seeking employment, economic factors such as recession or economic depression , among other factors, so this makes it difficult to categorize

2925-555: The late Paleolithic period, 40,000 BC, have been found in Spanish caves. Silver , copper , tin and meteoric iron can also be found in native form, allowing a limited amount of metalworking in early cultures. Early cold metallurgy, using native copper not melted from mineral has been documented at sites in Anatolia and at the site of Tell Maghzaliyah in Iraq , dating from the 7th/6th millennia BC. The earliest archaeological support of smelting (hot metallurgy) in Eurasia

2990-425: The management and operation of the equipment and instrumentation necessary to perform chemical analyzes than a chemical technician. They are part of the team of a chemical laboratory in which the quality of the raw material, intermediate products and finished products is analyzed. They also perform functions in the areas of environmental quality control and the operational phase of a chemical plant. In addition to all

3055-427: The mechanical properties of metals, the physical properties of metals, and the physical performance of metals. Topics studied in physical metallurgy include crystallography , material characterization , mechanical metallurgy, phase transformations , and failure mechanisms . Historically, metallurgy has predominately focused on the production of metals. Metal production begins with the processing of ores to extract

3120-917: The metal, and includes the mixture of metals to make alloys . Metal alloys are often a blend of at least two different metallic elements. However, non-metallic elements are often added to alloys in order to achieve properties suitable for an application. The study of metal production is subdivided into ferrous metallurgy (also known as black metallurgy ) and non-ferrous metallurgy , also known as colored metallurgy. Ferrous metallurgy involves processes and alloys based on iron , while non-ferrous metallurgy involves processes and alloys based on other metals. The production of ferrous metals accounts for 95% of world metal production. Modern metallurgists work in both emerging and traditional areas as part of an interdisciplinary team alongside material scientists and other engineers. Some traditional areas include mineral processing, metal production, heat treatment, failure analysis , and

3185-553: The noted exception of silicon, which is not a metal. Other forms include: In production engineering , metallurgy is concerned with the production of metallic components for use in consumer or engineering products. This involves production of alloys, shaping, heat treatment and surface treatment of product. The task of the metallurgist is to achieve balance between material properties, such as cost, weight , strength , toughness , hardness , corrosion , fatigue resistance and performance in temperature extremes. To achieve this goal,

3250-507: The operating environment must be carefully considered. Determining the hardness of the metal using the Rockwell, Vickers, and Brinell hardness scales is a commonly used practice that helps better understand the metal's elasticity and plasticity for different applications and production processes. In a saltwater environment, most ferrous metals and some non-ferrous alloys corrode quickly. Metals exposed to cold or cryogenic conditions may undergo

3315-482: The ore feed are broken through crushing or grinding in order to obtain particles small enough, where each particle is either mostly valuable or mostly waste. Concentrating the particles of value in a form supporting separation enables the desired metal to be removed from waste products. Mining may not be necessary, if the ore body and physical environment are conducive to leaching . Leaching dissolves minerals in an ore body and results in an enriched solution. The solution

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3380-402: The piece being treated. The compression stress in the surface of the material strengthens the part and makes it more resistant to fatigue failure, stress failures, corrosion failure, and cracking. Thermal spraying techniques are another popular finishing option, and often have better high temperature properties than electroplated coatings. Thermal spraying, also known as a spray welding process,

3445-450: The preferred choice for the highest administrative positions on big enterprises involved in chemistry-related duties. Some positions, especially research oriented, will only allow those chemists who are Ph.D. holders. Jobs that involve intensive research and actively seek to lead the discovery of completely new chemical compounds under specifically assigned monetary funds and resources or jobs that seek to develop new scientific theories require

3510-588: The principality of Halberstadt. In 1693, shortly after the establishment of the University of Halle , he was appointed primary professor of medicine and natural philosophy. During his career there, he held the position of rector three times. With the exception of four years (1708–1712), which he passed at Berlin in the capacity of royal physician, Hoffmann spent the rest of his life at Halle in instruction, practice and study, interrupted now and again by visits to different courts of Germany, where his services procured him honours and rewards. His fame became European. He

3575-445: The process of shot peening, small round shot is blasted against the surface of the part to be finished. This process is used to prolong the product life of the part, prevent stress corrosion failures, and also prevent fatigue. The shot leaves small dimples on the surface like a peen hammer does, which cause compression stress under the dimple. As the shot media strikes the material over and over, it forms many overlapping dimples throughout

3640-666: The product by a process called work hardening . Work hardening creates microscopic defects in the metal, which resist further changes of shape. Metals can be heat-treated to alter the properties of strength, ductility, toughness, hardness and resistance to corrosion. Common heat treatment processes include annealing, precipitation strengthening , quenching, and tempering: Often, mechanical and thermal treatments are combined in what are known as thermo-mechanical treatments for better properties and more efficient processing of materials. These processes are common to high-alloy special steels, superalloys and titanium alloys. Electroplating

3705-414: The responsibilities of that same job title. The level of supervision given to that chemist also varies in a similar manner, with factors similar to those that affect the tasks demanded for a particular chemist It is important that those interested in a Chemistry degree understand the variety of roles available to them (on average), which vary depending on education and job experience. Those Chemists who hold

3770-568: The start of the 20th century. At the Washington Academy of Sciences during World War I , it was said that the side with the best chemists would win the war. Jobs for chemists generally require at least a bachelor's degree in chemistry, which takes four years. However, many positions, especially those in research, require a Master of Science or a Doctor of Philosophy (PhD.). Most undergraduate programs emphasize mathematics and physics as well as chemistry, partly because chemistry

3835-771: The success of the Philistines . Historical developments in ferrous metallurgy can be found in a wide variety of past cultures and civilizations. This includes the ancient and medieval kingdoms and empires of the Middle East and Near East , ancient Iran , ancient Egypt , ancient Nubia , and Anatolia in present-day Turkey , Ancient Nok , Carthage , the Celts , Greeks and Romans of ancient Europe , medieval Europe, ancient and medieval China , ancient and medieval India , ancient and medieval Japan , amongst others. A 16th century book by Georg Agricola , De re metallica , describes

3900-552: The third millennium BC in Palmela , Portugal, Los Millares , Spain, and Stonehenge , United Kingdom. The precise beginnings, however, have not be clearly ascertained and new discoveries are both continuous and ongoing. In approximately 1900 BC, ancient iron smelting sites existed in Tamil Nadu . In the Near East , about 3,500 BC, it was discovered that by combining copper and tin,

3965-412: The training usually given to chemical technologists in their respective degree (or one given via an associate degree), a chemist is also trained to understand more details related to chemical phenomena so that the chemist can be capable of more planning on the steps to achieve a distinct goal via a chemistry-related endeavor. The higher the competency level achieved in the field of chemistry (as assessed via

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4030-409: Was a mystical force that transformed one substance into another and thus was of primary interest to mankind. It was fire that led to the discovery of iron and glasses . After gold was discovered and became a precious metal, many people were interested to find a method that could convert other substances into gold. This led to the protoscience called alchemy . The word chemist is derived from

4095-594: Was enrolled a member of many learned societies in different foreign countries (including being elected Fellow of the Royal Society in 1720), while in his own he became privy councillor. Hoffmann died on 12 November 1742 in Halle. Of his numerous writings a catalogue is to be found in Haller's Bibliotheca medicinae practicae . The chief is Medicina rationalis systematica , undertaken at the age of sixty, and published in 1730. It

4160-434: Was originally an alchemist 's term for the extraction of metals from minerals, the ending -urgy signifying a process, especially manufacturing: it was discussed in this sense in the 1797 Encyclopædia Britannica . In the late 19th century, metallurgy's definition was extended to the more general scientific study of metals, alloys, and related processes. In English , the / m ɛ ˈ t æ l ər dʒ i / pronunciation

4225-414: Was translated into French in 1739, under the title of Médecine raisonnée d'Hoffmann . A complete edition of Hoffmann's works, with a life of the author, was published at Geneva in 1740, to which supplements were added in 1753 and 1760. Editions appeared also at Venice in 1745 and at Naples in 1753 and 1793. At the instigation of Robert Boyle , he turned to the analysis and uses of mineral waters and became

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