1.
Geneva
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Geneva is the second most populous city in Switzerland and is the most populous city of Romandy, the French-speaking part of Switzerland. Situated where the Rhône exits Lake Geneva, it is the capital of the Republic, the municipality has a population of 198,072, and the canton has 484,736 residents. In 2014, the compact agglomération du Grand Genève had 946,000 inhabitants in 212 communities in both Switzerland and France, within Swiss territory, the commuter area named Métropole lémanique contains a population of 1.25 million. This area is essentially spread east from Geneva towards the Riviera area and north-east towards Yverdon-les-Bains, Geneva is the city that hosts the highest number of international organizations in the world. It is also the place where the Geneva Conventions were signed, Geneva was ranked as the worlds ninth most important financial centre for competitiveness by the Global Financial Centres Index, ahead of Frankfurt, and third in Europe behind London and Zürich. A2009 survey by Mercer found that Geneva has the third-highest quality of life of any city in the world, the city has been referred to as the worlds most compact metropolis and the Peace Capital. In 2009 and 2011, Geneva was ranked as, respectively, the city was mentioned in Latin texts, by Caesar, with the spelling Genava, probably from a Celtic toponym *genawa- from the stem *genu-, in the sense of a bending river or estuary. The medieval county of Geneva in Middle Latin was known as pagus major Genevensis or Comitatus Genevensis, the name takes various forms in modern languages, Geneva /dʒᵻˈniːvə/ in English, French, Genève, German, Genf, Italian, Ginevra, and Romansh, Genevra. The city in origin shares its name, *genawa estuary, with the Italian port city of Genoa, Geneva was an Allobrogian border town, fortified against the Helvetii tribe, when the Romans took it in 121 BC. It became Christian under the Late Roman Empire, and acquired its first bishop in the 5th century, having been connected to the bishopric of Vienne in the 4th. In the Middle Ages, Geneva was ruled by a count under the Holy Roman Empire until the late 14th century, around this time the House of Savoy came to dominate the city. In the 15th century, a republican government emerged with the creation of the Grand Council. In 1541, with Protestantism in the ascendancy, John Calvin, by the 18th century, however, Geneva had come under the influence of Catholic France, which cultivated the city as its own. France also tended to be at odds with the ordinary townsfolk, in 1798, revolutionary France under the Directory annexed Geneva. At the end of the Napoleonic Wars, on 1 June 1814, in 1907, the separation of Church and State was adopted. Geneva flourished in the 19th and 20th centuries, becoming the seat of international organizations. Geneva is located at 46°12 North, 6°09 East, at the end of Lake Geneva. It is surrounded by two chains, the Alps and the Jura
2.
Swiss made
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Swiss made is a label used to indicate that a product was made in Switzerland. From 2017, the criteria are, For food products, 80% of the weight of the raw materials. For industrial products, 60% of the costs and the essential manufacturing step must occur in Switzerland. For services, the headquarters and administration must be located in Switzerland. The wording was adopted in the late 19th century and is unique in that most other countries use the phrase Made in. The most obvious place where the label is found is on Swiss watches, the Swiss laws permit the use of the words Suisse, produit suisse, fabriqué en Suisse, qualité suisse or the translations, Swiss, Swiss Made, or Swiss Movement. On some older watches, for example, the word Swiss appears alone on the dial at the six oclock position, there are two discrete sections of the Swiss law that pertain to the use of the name Swiss made. The first law, which applies to all types of Swiss products, is the Loi sur la protection des marques, the text of either law is available in French, German or Italian, since those are the principal official languages of Switzerland. Currently the aforementioned Swiss legal standards permit watch brands or watchmakers to label watches Swiss Made under certain defined circumstances. These standards have changed over time and were not always codified in the national law, on the other hand, they might well exceed the current legal definition of Swiss made. Indeed, the current law of the applicability of Swiss made was codified on December 23,1971, thereafter, the law defines a Swiss watch, the definition of which is dependent on certain aspects of its movement. The law then goes on to define under what circumstances a watch movement may be considered Swiss made. The law then sets forth the conditions for the use of the name Swiss on watches, on cases, on watch movements, on watch dials. The pertinent parts of the law are digested below, in sum, a watch is considered Swiss whose movement is encased in Switzerland and whose final control by the Manufacture dhorlogerie takes place in Switzerland. Often the Swissness of a watch is largely dependent on the brand and its reputation and for reason, among others. The Swiss Federal Council modified the ordinance regulating the use of the Swiss name for watches in 1995 and this revision was explained in a press release entitled Des composants étrangers pour les montres. From 1 January 2017, the law set the minimum at 60 percent, a watch that says Swiss Quartz is considered to be a proper Swiss watch. However, it is improperly used by foreign manufacturers to merely indicate that the quartz movement is of Swiss origin
3.
Watch
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A watch is a small timepiece intended to be carried or worn by a person. It is designed to keep working despite the motions caused by the persons activities, a wristwatch is designed to be worn around the wrist, attached by a watch strap or other type of bracelet. A pocket watch is designed for a person to carry in a pocket, watches evolved in the 17th century from spring-powered clocks, which appeared as early as the 14th century. During most of its history the watch was a device, driven by clockwork, powered by winding a mainspring. In the 1960s the electronic quartz watch was invented, which was powered by a battery, by the 1980s the quartz watch had taken over most of the market from the mechanical watch. Today most inexpensive and medium-priced watches, used mainly for timekeeping, have quartz movements, various extra features, called complications, such as moon-phase displays and the different types of tourbillon, are sometimes included. Modern watches often display the day, date, month and year, time-related features such as timers, chronographs and alarm functions are common. Some modern designs incorporate calculators, GPS and Bluetooth technology or have heart-rate monitoring capabilities, some watches use radio clock technology to regularly correct the time. Developments in the 2010s include smartwatches, which are elaborate computer-like electronic devices designed to be worn on a wrist and they generally incorporate timekeeping functions, but these are only small fractions of what the smartwatch can do. The study of timekeeping is known as horology, watches evolved from portable spring-driven clocks, which first appeared in 15th century Europe. Watches werent widely worn in pockets until the 17th century, one account says that the word watch came from the Old English word woecce which meant watchman, because it was used by town watchmen to keep track of their shifts at work. Another says that the term came from 17th century sailors, who used the new mechanisms to time the length of their shipboard watches, the increased accuracy of the balance wheel focused attention on errors caused by other parts of the movement, igniting a two-century wave of watchmaking innovation. The first thing to be improved was the escapement, the verge escapement was replaced in quality watches by the cylinder escapement, invented by Thomas Tompion in 1695 and further developed by George Graham in the 1720s. The British had predominated in watch manufacture for much of the 17th and 18th centuries, aaron Lufkin Dennison started a factory in 1851 in Massachusetts that used interchangeable parts, and by 1861 it was running a successful enterprise incorporated as the Waltham Watch Company. The concept of the wristwatch goes back to the production of the very earliest watches in the 16th century, elizabeth I of England received a wristwatch from Robert Dudley in 1571, described as an arm watch. The oldest surviving wristwatch is one made in 1806 and given to Joséphine de Beauharnais, from the beginning, wrist watches were almost exclusively worn by women, while men used pocket-watches up until the early 20th century. The Garstin Company of London patented a Watch Wristlet design in 1893, officers in the British Army began using wristwatches during colonial military campaigns in the 1880s, such as during the Anglo-Burma War of 1885. In continental Europe Girard-Perregaux and other Swiss watch makers began supplying German naval officers with wrist watches in about 1880 and these early models were essentially standard pocket-watches fitted to a leather strap but, by the early 20th century, manufacturers began producing purpose-built wristwatches
4.
Napoleon
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Napoleon Bonaparte was a French military and political leader who rose to prominence during the French Revolution and led several successful campaigns during the French Revolutionary Wars. As Napoleon I, he was Emperor of the French from 1804 until 1814, Napoleon dominated European and global affairs for more than a decade while leading France against a series of coalitions in the Napoleonic Wars. He won most of these wars and the vast majority of his battles, one of the greatest commanders in history, his wars and campaigns are studied at military schools worldwide. Napoleons political and cultural legacy has ensured his status as one of the most celebrated and he was born Napoleone di Buonaparte in Corsica to a relatively modest family from the minor nobility. When the Revolution broke out in 1789, Napoleon was serving as an officer in the French army. Seizing the new opportunities presented by the Revolution, he rose through the ranks of the military. The Directory eventually gave him command of the Army of Italy after he suppressed a revolt against the government from royalist insurgents, in 1798, he led a military expedition to Egypt that served as a springboard to political power. He engineered a coup in November 1799 and became First Consul of the Republic and his ambition and public approval inspired him to go further, and in 1804 he became the first Emperor of the French. Intractable differences with the British meant that the French were facing a Third Coalition by 1805, in 1806, the Fourth Coalition took up arms against him because Prussia became worried about growing French influence on the continent. Napoleon quickly defeated Prussia at the battles of Jena and Auerstedt, then marched the Grand Army deep into Eastern Europe, France then forced the defeated nations of the Fourth Coalition to sign the Treaties of Tilsit in July 1807, bringing an uneasy peace to the continent. Tilsit signified the high watermark of the French Empire, hoping to extend the Continental System and choke off British trade with the European mainland, Napoleon invaded Iberia and declared his brother Joseph the King of Spain in 1808. The Spanish and the Portuguese revolted with British support, the Peninsular War lasted six years, featured extensive guerrilla warfare, and ended in victory for the Allies. The Continental System caused recurring diplomatic conflicts between France and its client states, especially Russia, unwilling to bear the economic consequences of reduced trade, the Russians routinely violated the Continental System and enticed Napoleon into another war. The French launched an invasion of Russia in the summer of 1812. The resulting campaign witnessed the collapse of the Grand Army, the destruction of Russian cities, in 1813, Prussia and Austria joined Russian forces in a Sixth Coalition against France. A lengthy military campaign culminated in a large Allied army defeating Napoleon at the Battle of Leipzig in October 1813, the Allies then invaded France and captured Paris in the spring of 1814, forcing Napoleon to abdicate in April. He was exiled to the island of Elba near Rome and the Bourbons were restored to power, however, Napoleon escaped from Elba in February 1815 and took control of France once again. The Allies responded by forming a Seventh Coalition, which defeated Napoleon at the Battle of Waterloo in June, the British exiled him to the remote island of Saint Helena in the South Atlantic, where he died six years later at the age of 51
5.
Pope Pius XI
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Pope Pius XI, born Ambrogio Damiano Achille Ratti, reigned as Pope from 6 February 1922 to his death in 1939. He was the first sovereign of Vatican City from its creation as an independent state on 11 February 1929 and he took as his papal motto, Pax Christi in Regno Christi, translated The Peace of Christ in the Kingdom of Christ. During his pontificate, the hostility with the Italian government over the status of the papacy. He was unable to stop the persecution of the Church and the killing of clergy in Mexico, Spain and he canonized important saints, including Thomas More, Petrus Canisius, Konrad von Parzham, Andrew Bobola and Don Bosco. Pius XI created the feast of Christ the King in response to anti-clericalism and he took a strong interest in fostering the participation of lay people throughout the Catholic Church, especially in the Catholic Action movement. The end of his pontificate was dominated by speaking out against Hitler and Mussolini and defending the Catholic Church from intrusions into Catholic life and he died on 10 February 1939 in the Apostolic Palace and is buried in the Papal Grotto of Saint Peters Basilica. In the course of excavating space for his tomb, two levels of burial grounds were uncovered which revealed bones now venerated as the bones of St. Peter. Achille Ratti was born in Desio, in the province of Milan, in 1857 and he was ordained a priest in 1879 and embarked on an academic career within the Church. He obtained three doctorates at the Gregorian University in Rome, and then from 1882 to 1888 was a professor at the seminary in Padua and his scholarly specialty was as an expert paleographer, a student of ancient and medieval Church manuscripts. Eventually, he left teaching to work full-time at the Ambrosian Library in Milan. During this time, he edited and published an edition of the Ambrosian Missal and he became chief of the Library in 1907 and undertook a thorough programme of restoration and re-classification of the Ambrosians collection. He was also a mountaineer in his spare time, reaching the summits of Monte Rosa. The combination of a pope would not be seen again until the pontificate of John Paul II. In 1911, at Pope Pius Xs invitation, he moved to the Vatican to become Vice-Prefect of the Vatican Library, in October 1918, Benedict was the first head of state to congratulate the Polish people on the occasion of the restoration of their independence. In March 1919, he nominated ten new bishops and, soon after, Ratti was consecrated as a titular archbishop in October 1919. Benedict XV and Nuncio Ratti repeatedly cautioned Polish authorities against persecuting the Lithuanian and Ruthenian clergy, Ratti intended to work for Poland by building bridges to men of goodwill in the Soviet Union, even to shedding his blood for Russia. Benedict, however, needed Ratti as a diplomat, not as a martyr, the nuncios continued contacts with Russians did not generate much sympathy for him within Poland at the time. After Pope Benedict sent Ratti to Silesia to forestall potential political agitation within the Polish Catholic clergy, on 20 November, when German Cardinal Adolf Bertram announced a papal ban on all political activities of clergymen, calls for Rattis expulsion climaxed
6.
Edward VIII
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Edward VIII was King of the United Kingdom and the Dominions of the British Empire, and Emperor of India, from 20 January 1936 until his abdication on 11 December the same year. Edward was the eldest son of George V and Mary of Teck and he was named Prince of Wales on his sixteenth birthday, nine weeks after his father succeeded as king. As a young man, he served in the British Army during the First World War, Edward became king on his fathers death in early 1936. However, he showed impatience with court protocol, and caused concern among politicians by his apparent disregard for established constitutional conventions. Only months into his reign, he caused a crisis by proposing marriage to Wallis Simpson. When it became apparent that he could not marry Wallis and remain on the throne and he was succeeded by his younger brother, George VI. With a reign of 326 days, Edward was one of the monarchs in British history. After his abdication, he was created Duke of Windsor and he married Wallis in France on 3 June 1937, after her second divorce became final. Later that year, the couple toured Germany, after the war, Edward spent the rest of his life in retirement in France. Edward was born on 23 June 1894 at White Lodge, Richmond Park and he was the eldest son of the Duke and Duchess of York. His father was the son of the Prince and Princess of Wales and his mother was the eldest daughter of Francis and Mary Adelaide, Duke and Duchess of Teck. At the time of his birth, he was third in the line of succession to the throne and he was baptised Edward Albert Christian George Andrew Patrick David in the Green Drawing Room of White Lodge on 16 July 1894 by Edward White Benson, Archbishop of Canterbury. The names were chosen in honour of Edwards late uncle, who was known to his family as Eddy or Edward and he was always known to his family and close friends by his last given name, David. As was common practice with children of the time, Edward. One of Edwards early nannies often abused him by pinching him before he was due to be presented to his parents and his subsequent crying and wailing would lead the Duke and Duchess to send him and the nanny away. The nanny was discharged after her mistreatment of the children was discovered, Edwards father, though a harsh disciplinarian, was demonstrably affectionate, and his mother displayed a frolicsome side with her children that belied her austere public image. She was amused by the children making tadpoles on toast for their French master, initially Edward was tutored at home by Helen Bricka. Upon his parents return, Edward was placed under the care of two men, Frederick Finch and Henry Hansell, who brought up Edward and his brothers
7.
Harry S. Truman
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Harry S. Truman was an American politician who served as the 33rd President of the United States, assuming the office upon the death of Franklin D. Roosevelt during the waning months of World War II. In domestic affairs, he was a moderate Democrat whose liberal proposals were a continuation of Franklin Roosevelts New Deal, but the conservative-dominated Congress blocked most of them. He also used weapons to end World War II, desegregated the U. S. armed forces, supported a newly independent Israel. Truman was born in Lamar, Missouri, and spent most of his youth on his familys 600-acre farm near Independence, in the last months of World War I, he served in combat in France as an artillery officer with his National Guard unit. After the war, he owned a haberdashery in Kansas City, Missouri, and joined the Democratic Party. Truman was first elected to office as a county official in 1922. After serving as a United States Senator from Missouri and briefly as Vice President, he succeeded to the presidency on April 12,1945, upon the death of Franklin D. Roosevelt. Germany surrendered on Trumans 61st birthday, just a few weeks after he assumed the presidency, but the war with Imperial Japan raged on and was expected to last at least another year. Although this decision and the issues that arose as a result of it remain the subject of debate to this day. Truman presided over a surge in economic prosperity as America sought readjustment after long years of depression. His presidency was a point in foreign affairs, as the United States engaged in an internationalist foreign policy. Truman helped found the United Nations in 1945, issued the Truman Doctrine in 1947 to contain Communism and his political coalition was based on the white South, labor unions, farmers, ethnic groups, and traditional Democrats across the North. Truman was able to rally groups of supporters during the 1948 presidential election. The Soviet Union became an enemy in the Cold War, Truman oversaw the Berlin Airlift of 1948 and the creation of NATO in 1949, but was unable to stop Communists from taking over China. When communist North Korea invaded South Korea in 1950, he sent U. S. troops, after initial successes in Korea, however, the UN forces were thrown back by Chinese intervention, and the conflict was stalemated throughout the final years of Trumans presidency. Scholars, starting in 1962, ranked Trumans presidency as near great, Harry S. Truman was born on May 8,1884, in Lamar, Missouri, the oldest child of John Anderson Truman and Martha Ellen Young Truman. His parents chose the name Harry after his mothers brother, Harrison Harry Young, while the S did not stand for any one name, it was chosen as his middle initial to honor both of his grandfathers, Anderson Shipp Truman and Solomon Young. The initial has been written and printed followed by a period
8.
French Revolution
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Through the Revolutionary Wars, it unleashed a wave of global conflicts that extended from the Caribbean to the Middle East. Historians widely regard the Revolution as one of the most important events in human history, the causes of the French Revolution are complex and are still debated among historians. Following the Seven Years War and the American Revolutionary War, the French government was deeply in debt, Years of bad harvests leading up to the Revolution also inflamed popular resentment of the privileges enjoyed by the clergy and the aristocracy. Demands for change were formulated in terms of Enlightenment ideals and contributed to the convocation of the Estates-General in May 1789, a central event of the first stage, in August 1789, was the abolition of feudalism and the old rules and privileges left over from the Ancien Régime. The next few years featured political struggles between various liberal assemblies and right-wing supporters of the intent on thwarting major reforms. The Republic was proclaimed in September 1792 after the French victory at Valmy, in a momentous event that led to international condemnation, Louis XVI was executed in January 1793. External threats closely shaped the course of the Revolution, internally, popular agitation radicalised the Revolution significantly, culminating in the rise of Maximilien Robespierre and the Jacobins. Large numbers of civilians were executed by revolutionary tribunals during the Terror, after the Thermidorian Reaction, an executive council known as the Directory assumed control of the French state in 1795. The rule of the Directory was characterised by suspended elections, debt repudiations, financial instability, persecutions against the Catholic clergy, dogged by charges of corruption, the Directory collapsed in a coup led by Napoleon Bonaparte in 1799. The modern era has unfolded in the shadow of the French Revolution, almost all future revolutionary movements looked back to the Revolution as their predecessor. The values and institutions of the Revolution dominate French politics to this day, the French Revolution differed from other revolutions in being not merely national, for it aimed at benefiting all humanity. Globally, the Revolution accelerated the rise of republics and democracies and it became the focal point for the development of all modern political ideologies, leading to the spread of liberalism, radicalism, nationalism, socialism, feminism, and secularism, among many others. The Revolution also witnessed the birth of total war by organising the resources of France, historians have pointed to many events and factors within the Ancien Régime that led to the Revolution. Over the course of the 18th century, there emerged what the philosopher Jürgen Habermas called the idea of the sphere in France. A perfect example would be the Palace of Versailles which was meant to overwhelm the senses of the visitor and convince one of the greatness of the French state and Louis XIV. Starting in the early 18th century saw the appearance of the sphere which was critical in that both sides were active. In France, the emergence of the public sphere outside of the control of the saw the shift from Versailles to Paris as the cultural capital of France. In the 1750s, during the querelle des bouffons over the question of the quality of Italian vs, in 1782, Louis-Sébastien Mercier wrote, The word court no longer inspires awe amongst us as in the time of Louis XIV
9.
Pantograph
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A pantograph is a mechanical linkage connected in a manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a second pen. If a line drawing is traced by the first point, an identical, enlarged, using the same principle, different kinds of pantographs are used for other forms of duplication in areas such as sculpture, minting, engraving and milling. Because of the shape of the device, a pantograph also refers to a kind of structure that can compress or extend like an accordion. This can be found in extension arms for wall-mounted mirrors, temporary fences, scissor lifts, the first pantograph was constructed in 1603 by Christoph Scheiner, who used the device to copy and scale diagrams, but he wrote about the invention over 27 years later, in Pantographice. One arm of the pantograph contained a pointer, while the other held a drawing implement, and by moving the pointer over a diagram. By changing the positions of the arms in the linkage between the arm and drawing arm, the scale of the image produced can be changed. In 1821, Professor William Wallace invented the eidograph to improve upon the practical utility of the pantograph, the eidograph relocates the fixed point to the center of the parallelogram and uses a narrow parallelogram to provide improved mechanical advantages. The original use of the pantograph was for copying and scaling line drawings, modern versions are sold as toys. By adjusting the needles different enlargement or reduction ratios can be achieved, chevertons machine was fitted with a rotating cutting bit to carve reduced versions of well-known sculptures. Of course a three-dimensional pantograph can also be used to enlarge sculpture by interchanging the position of the model, another version is still very much in use to reduce the size of large relief designs for coins down to the required size of the coin. One advantage of phonograph and gramophone discs over cylinders in the 1890s—before electronic amplification was available—was that large numbers of discs could be stamped quickly and cheaply, when molding improved somewhat, molded cylinders were used as pantograph masters. This was employed by Edison and Columbia in 1898, and was used until about January 1902, some companies like the United States Phonograph Co. of Newark, New Jersey, supplied cylinder masters for smaller companies so that they could duplicate them, sometimes pantographically. Pantographs could turn out about 30 records per day and produce up to about 150 records per master, in theory, pantograph masters could be used for 200 or 300 duplicates if the master and the duplicate were running in reverse and the record would be duplicated in reverse. This, in theory, could extend the usability of a master by using the unworn/lesser worn part of the recording for duplication. Pathé employed this system with mastering their vertically-cut records until 1923 and this was done as the resulting cylinder was considerably loud and of very high fidelity. This system resulted in some fidelity reduction and rumble, but relatively high quality sound, Edison Diamond Disc Records were made by recording directly onto the wax master disc. If the milling head was mounted on a pantograph, a part could be cut simply by tracing a template. This was essentially the same concept as reproducing documents with a pen-equipped pantograph, Pantograph routing, which is conceptually identical to pantograph milling, also exists
10.
Balance wheel
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A balance wheel, or balance, is the timekeeping device used in mechanical watches and some clocks, analogous to the pendulum in a pendulum clock. It is a wheel that rotates back and forth, being returned toward its center position by a spiral torsion spring. It is driven by the escapement, which transforms the motion of the watch gear train into impulses delivered to the balance wheel. Each swing of the wheel allows the train to advance a set amount. From its invention in the 14th century until tuning fork and quartz movements became available in the 1960s, virtually every portable timekeeping device used some form of balance wheel. Modern watch balance wheels are made of Glucydur, a low thermal expansion alloy of beryllium, copper and iron. The two alloys are matched so their residual temperature responses cancel out, resulting in lower temperature error. The wheels are smooth, to air friction, and the pivots are supported on precision jewel bearings. Older balance wheels used weight screws around the rim to adjust the poise, Balance wheels rotate about 1½ turns with each swing, that is, about 270° to each side of their center equilibrium position. The rate of the wheel is adjusted with the regulator. This holds the part of the spring behind the slit stationary, moving the lever slides the slit up and down the balance spring, changing its effective length, and thus the resonant vibration rate of the balance. Since the regulator interferes with the action, chronometers and some precision watches have ‘free sprung’ balances with no regulator. Their rate is adjusted by weight screws on the balance rim, a balances vibration rate is traditionally measured in beats per hour, or BPH, although beats per second and Hz are also used. The length of a beat is one swing of the balance wheel, balances in precision watches are designed with faster beats, because they are less affected by motions of the wrist. Alarm clocks and kitchen timers often have a rate of 4 beats per second, Watches made prior to the 1970s usually had a rate of 5 beats per second. Current watches have rates of 6,8 and a few have 10 beats per second, during WWII, Elgin produced a very precise stopwatch that ran at 40 beats per second, earning it the nickname Jitterbug. Audemars Piguet currently produces a movement that allows for a high balance vibration of 12 beats/s. The precision of the best balance wheel watches on the wrist is around a few seconds per day, the most accurate balance wheel timepieces made were marine chronometers, which by WWII had achieved accuracies of 0.1 second per day
11.
Palladium
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Palladium is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston and he named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals and these have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, Palladium is also used in electronics, dentistry, medicine, hydrogen purification, chemical applications, groundwater treatment, and jewelry. Palladium is a key component of cells, which react hydrogen with oxygen to produce electricity, heat. Ore deposits of palladium and other PGMs are rare, recycling is also a source, mostly from scrapped catalytic converters. The numerous applications and limited supply sources result in considerable investment interest, Palladium belongs to group 10 in the periodic table, but the configuration in the outermost electron shells is atypical for group 10. Fewer electron shells are filled than the directly preceding it. The valence shell has eighteen electrons – ten more than the eight found in the shells of the noble gases from neon onward. Palladium is a soft metal that resembles platinum. It is the least dense and has the lowest melting point of the platinum group metals and it is soft and ductile when annealed and is greatly increased in strength and hardness when cold-worked. Palladium dissolves slowly in concentrated acid, in hot, concentrated sulfuric acid. It dissolves readily at room temperature in aqua regia, common oxidation states of palladium are 0, +1, +2 and +4. Palladium was first observed in 2002, Palladium films with defects produced by alpha particle bombardment at low temperature exhibit superconductivity having Tc=3.2 K. Naturally occurring palladium is composed of seven isotopes, six of which are stable, the most stable radioisotopes are 107Pd with a half-life of 6.5 million years, 103Pd with 17 days, and 100Pd with 3.63 days. Eighteen other radioisotopes have been characterized with atomic weights ranging from 90.94948 u to 122.93426 u and these have half-lives of less than thirty minutes, except 101Pd, 109Pd, and 112Pd. For isotopes with atomic mass unit values less than that of the most abundant stable isotope, 106Pd, the primary mode of decay for those isotopes of Pd with atomic mass greater than 106 is beta decay with the primary product of this decay being silver. Radiogenic 107Ag is a product of 107Pd and was first discovered in 1978 in the Santa Clara meteorite of 1976
12.
Bronze
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These additions produce a range of alloys that may be harder than copper alone, or have other useful properties, such as stiffness, ductility, or machinability. The archeological period where bronze was the hardest metal in use is known as the Bronze Age. In the ancient Near East this began with the rise of Sumer in the 4th millennium BC, with India and China starting to use bronze around the same time, everywhere it gradually spread across regions. The Bronze Age was followed by the Iron Age starting from about 1300 BC and reaching most of Eurasia by about 500 BC, the discovery of bronze enabled people to create metal objects which were harder and more durable than previously possible. Bronze tools, weapons, armor, and building such as decorative tiles were harder and more durable than their stone. It was only later that tin was used, becoming the major ingredient of bronze in the late 3rd millennium BC. Tin bronze was superior to arsenic bronze in that the process could be more easily controlled. Also, unlike arsenic, metallic tin and fumes from tin refining are not toxic, the earliest tin-alloy bronze dates to 4500 BCE in a Vinča culture site in Pločnik. Other early examples date to the late 4th millennium BC in Africa, Susa and some ancient sites in China, Luristan, ores of copper and the far rarer tin are not often found together, so serious bronze work has always involved trade. Tin sources and trade in ancient times had a influence on the development of cultures. In Europe, a source of tin was the British deposits of ore in Cornwall. In many parts of the world, large hoards of bronze artefacts are found, suggesting that bronze also represented a store of value, in Europe, large hoards of bronze tools, typically socketed axes, are found, which mostly show no signs of wear. With Chinese ritual bronzes, which are documented in the inscriptions they carry and from other sources and these were made in enormous quantities for elite burials, and also used by the living for ritual offerings. Pure iron is soft, and the process of beating and folding sponge iron to wrought iron removes from the metal carbon. Careful control of the alloying and tempering eventually allowed for wrought iron with properties comparable to modern steel, Bronze was still used during the Iron Age, and has continued in use for many purposes to the modern day. Among other advantages, it does not rust, the weaker wrought iron was found to be sufficiently strong for many uses. Archaeologists suspect that a disruption of the tin trade precipitated the transition. The population migrations around 1200–1100 BC reduced the shipping of tin around the Mediterranean, limiting supplies, there are many different bronze alloys, but typically modern bronze is 88% copper and 12% tin
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