Civilization - SNES - Civilopedia em Inglês
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CIVILOPÉDIA EM INGLÊS - CIVILIZATION II
Palace
PEDIAIMPROVE1
When populations began to organize their communities into cities, their governments became more structured and formalized. At an early stage, the ruler of the city established headquarters from which the business of running the city was conducted. In many cases, these buildings also served as the living quarters of the ruler. In wealthy cities, these facilities often expanded into immense, sprawling palaces. These richly adorned, imposing buildings were a source of civic pride, and helped to reinforce the aura of power surrounding the ruler.
Barracks
PEDIAIMPROVE2
Warfare has been a recurring phenomenon throughout the history of mankind, and it continues to plague the world today. Although war is not a desirable situation, it is important that even the most peaceful of societies be prepared for the possibility of war. When warring nations are closely matched in technology and manpower, battles are usually won by the army with the best training. Military schools and academies exist all over the world, established for the purpose of training military personnel in the latest methods, tactics, and technology. Men and women who graduate from such facilities possess higher than average command and military and technological skills, making them more effective in combat situations.
Granary
PEDIAIMPROVE3
Early humans were nomadic, settling in specific regions only for brief periods of time. When the food supply was exhausted in one area, the nomads would move on to search for more. Cities became possible only when the development of agriculture made the supply of food more abundant and dependable. However, cities still needed a way to keep the food supply stable throughout all four seasons. To do so, the citizens had to come up with a way to store seasonal crops for later use. The Granary was designed for the storage and protection of surplus food. Food storage technology meant that a smaller percentage of the population could produce and store enough food for everyone, allowing the remainder to pursue other jobs and activities.
Temple
PEDIAIMPROVE4
In ancient times, almost every city had a temple dedicated to the city's patron god. Many cities also had temples dedicated to other gods as well. In modern times temples are thought of as places of worship, like churches and cathedrals. Ancient societies, however, considered temples to be the local dwelling place for the god or goddess to whom they were dedicated. The faithful citizens brought gifts of food, rare metals, and spices to the temple as a sign of homage and respect. The presence of a temple in the city had a comforting effect on the population, and wise rulers often constructed one as soon as the city began to grow.
Marketplace
PEDIAIMPROVE5
As cities grew and prospered, trade between the farmers, artisans, and craftsmen who lived in the vicinity contributed to the economic health of the city. It soon became apparent that the best way for conducting trade within the city was to have a central location, or marketplace, where the people offering goods and services, or seeking them, could meet and conduct business. As a city's marketplace grew larger and more active, the economic vitality of the city grew as well.
Library
PEDIAIMPROVE6
The development of writing meant that the accumulated knowledge of a society could be written down and stored rather than memorized and passed along by word of mouth. The accumulated written material was stored in a library. The libraries of the ancient world, especially those at Alexandria and Pergamum, became leading centers of science and scholarship. The librarians actively collected the books of the world, accelerating the spread of knowledge.
Courthouse
PEDIAIMPROVE7
As kingdoms and empires expanded, it became increasingly difficult for the rulers to maintain control over the more distant regions of their realm. To ensure that the far-flung cities of the empire contributed their expected share of duties and taxes to the government, local magistrates and courts were established. In the courthouse, the ruler's representatives listened to the grievances of the people and defined and enforced the laws that governed social interaction. This reduced crime, and thereby kept the local population productive.
City Walls
PEDIAIMPROVE8
Before the establishment of centralized governments capable of supporting strong, national armies, individual cities were left to fend for themselves when it came to defense. As a result, many cities constructed city walls to protect against raiders and bandits. City walls represented a major investment in both time and materials, requiring years to complete and constant repairs to maintain their strength and integrity. However, these walls turned the city into a fortress capable of withstanding all but the most determined attack.
Aqueduct
PEDIAIMPROVE9
A major obstacle to population growth and expansion in early cities was the scarcity of water. In many cases, the solution to this problem was an aqueduct. Aqueducts were large, elevated stone "canals" through which water from nearby hills and mountains was channeled into the city. Aqueducts allowed cities to grow much larger by significantly increasing the amount of available water. At the same time aqueducts reduced the chance of contracting water-borne diseases, by reducing the dependence on stagnant ponds and wells as water sources. Aqueducts also allowed cities to be built in normally inhospitable environments, such as deserts, by providing an outside water source. Modern day Los Angles, for example, obtains its water supply from the Colorado River, through a system of aqueducts over 200 miles long.
Bank
PEDIAIMPROVE10
A highly developed banking system is one of the cornerstones of an advanced
civilization. Banks lend money to individuals or groups, providing capital for
industrial and real estate development. Banks also contribute to the economic
growth of a city or region by stimulating the development of production
facilities. Individual citizens can also benefit by investing their own
surplus money in the bank and earning interest on it.
Cathedral
PEDIAIMPROVE11
Throughout the Dark Ages that followed the fall of the Roman Empire, the Christian Church was a major influence in the revival of European civilization. In recognition of the expanding influence of the church, great cathedrals were built in the largest towns and cities, to act as centers of religious study and worship. In addition to their religious significance, cathedrals acted as the center of social and cultural activity in the town. They brought great pride, stability, and tradition to the citizens of the community.
University
PEDIAIMPROVE12
Universities are institutions of higher learning. Early universities, established in the Middle Ages, were usually built in cities that had a large or important cathedral. Studies at these institutions focused on matters concerning the church. The curricula quickly expanded to include classical art, literature, and languages. Modern universities provide the opportunity to study a wide array of subjects. They have also become centers for research into many fields, serving as the source of major advances in computers, medicine, physics, and a variety of other subjects.
Mass Transit
PEDIAIMPROVE13
Within a few decades of the invention of the automobile, the horse-drawn carriage disappeared from city streets. Along with all the advantages offered by the automobile, this new means of transportation quickly became a significant source of air pollution. As larger cities became more crowded, the number of cars increased, making travel difficult and adding to the pollution problem as automobile traffic clogged the streets. The development of mass transit systems, including busses, trolleys, subways, and light rail, led to a reduction in traffic and, as a result, a reduction in air pollution.
Colosseum
PEDIAIMPROVE14
The original colosseum provided entertainment for the common people of Roman society by presenting them with spectacles and events as a temporary escape from day-to-day life. This concept has been revived in the 20th Century. Modern-day stadiums and civic centers provide an arena for entertainment ranging from concerts to professional sporting events. Although the violent spectacle of gladiatorial combat is a thing of the past, today's colosseums still provide entertainment and diversion for the masses.
Factory
PEDIAIMPROVE15
Early examples of factory-like production, where a number of individuals work cooperatively to produce goods for sale or trade, can be found as far back as ancient Greece and Rome. Modern factories, however, evolved from the concept of specialized labor, where each worker performed a single step in the overall production of an item. This specialization allows factories to increase the speed and efficiency of the manufacturing process, far surpassing earlier means of production. The development of the factory system as a means of production played a key role in the Industrial Revolution.
Manufacturing Plant
PEDIAIMPROVE16
Manufacturing plants are large industrial complexes that produce goods of all types, although they are generally used to produce durable consumer goods such as automobiles. Essentially, a manufacturing plant is a large, sophisticated factory that employs specialization of labor, complex machinery, and assembly lines to gain efficiency and economies of scale. This combination of manpower and automation increases productivity and reduces production costs.
SDI Defense
PEDIAIMPROVE17
Historically, research in the area of warfare has seen the development of powerful new weapons closely followed by the development of defenses to counteract the weapons' destructive power. The development of nuclear weapons seemed to be the exception to this rule: for the first time, mankind had created a weapon to which there was apparently no effective defense. SDI (Strategic Defense Initiative), however, could be the answer to this problem. Using laser-equipped orbital satellites or ground-launched ABMs (Anti-Ballistic Missiles) to intercept and destroy enemy nuclear missiles in mid-air, the SDI Defense offers the first hope of negating the threat posed by nuclear missiles.
Recycling Center
PEDIAIMPROVE18
The continual growth in city populations leads to an inevitable increase in garbage. Eventually, existing landfills and garbage dumps are filled, forcing new dumping sites to be established. This leads to the gradual but steady destruction of the local environment. To reverse this problem, many areas have established recycling centers, where much of the garbage is sorted and reduced to reusable components through various means. These components are then used to manufacture new products. In this way, much of the trash produced is turned into raw materials for production, rather than contributing to the ever-increasing pollution problem.
Power Plant
PEDIAIMPROVE19
Power plants burn coal and other fossil fuels to produce the heat and steam necessary to run generators that produce electrical power. When electricity became widely and cheaply available, it meant that industries could convert from steam to electrical power to run their machinery. One central power plant could supply the electrical needs of a relatively large geographic area. However, increasing demands for electricity, by both consumer and commercial customers, led to a rise in the number of power plants. This, in turn, led to problems with air pollution. As more plants went on line, more fossil fuels were burned to generate power. Because modern society depends so heavily on electricity, researchers are constantly searching for alternate forms of energy to satisfy ever-increasing demands.
Hydro Plant
PEDIAIMPROVE20
One alternative to power generation utilizing coal or petroleum fuels is the hydroelectric power plant. This facility utilizes the energy of rapidly moving water to turn the turbines of its generators and produce electricity. In locations where a source of moving water is available, hydro plants offer a clean, safe alternative to coal, petroleum, and nuclear power generation. Hydro plants have their own set of environmental dangers, however. The disruption of a river's normal flow and the massive flooding of the land behind the facility's dam can destroy the habitat of the wildlife inhabiting the river basin.
Nuclear Plant
PEDIAIMPROVE21
Nuclear power plants utilize radioactive materials and the process of nuclear fission to generate the heat and steam needed to run electrical generators and produce electricity. Because nuclear power doesn't cause the air pollution associated with the burning of coal or petroleum products, this means of generating power is considered a viable alternative energy source. However, the toxic nature of the byproducts produced by the fission process creates serious problems of its own. No method of safely disposing of this toxic waste has been found, and the volatile nature of the fission reaction can lead to a meltdown of the reactor core if the reaction is not properly controlled. Because of these problems, the future of nuclear power is uncertain.
Stock Exchange
PEDIAIMPROVE22
In a free market economy, corporations often raise operating and development capital by selling "shares" in the corporation to private investors. These shares, which allow investors to share in the company's profits, were originally sold by brokers and privately hired auctioneers. Early European stock exchanges, such as the Paris Bourse, allowed anyone to buy and sell stock. However, it was quickly discovered that a formalized system was necessary in order to enforce transactions. Thereafter, membership in the exchange was required in order to buy and sell. The first formal stock exchange in the U.S. was established in 1791 in Philadelphia, and the New York Stock Exchange was established a year later. Today, stock exchanges are located in many major cities and commercial centers around the world. Private investment in corporations is vital to capitalistic economies, allowing corporations to grow more quickly than would otherwise be possible. The profits and new jobs created as a result improve the economy as a whole.
Sewer System
PEDIAIMPROVE23
One of the byproducts of large urban centers is a vast amount of human waste. As the city continues to grow, steps need to be taken to move the sewage away from inhabited areas and "treat" it so that it does not become a health hazard to humans or harm the local ecosystem. Sewer systems carry wastewater to treatment plants where the raw sewage is broken down through filtration and chemical processes to remove solids and harmful bacteria. The treated byproduct is then released into rivers and other waterways, where it is eventually washed safely into the ocean.
Supermarket
PEDIAIMPROVE24
Supermarkets are large, self-service retail stores that sell a wide variety of
food items and household goods to the general public. The first true
supermarket, King Kullen, was established in 1930 in the borough of Queens,
New York City, by Michael Cullen. Improved storage techniques and
refrigeration allowed supermarkets to stock and sell perishable foods in large
quantities, reducing the price to the consumer. The combination of ready
availability and low prices made the supermarket an instant success in the
U.S. during the years of the Great Depression. The supermarket continues to
grow in popularity in countries around the world.
Superhighways
PEDIAIMPROVE25
Early in his career, President Eisenhower traveled by road, from coast to coast, across the United States. This trip, which took nearly a month because of the poor system of roads, convinced him that it was necessary to make all areas of the country easily accessible. Not only were these improvements important to the growing number of people traveling by automobile, they could prove invaluable for the movement of troops and military equipment should the need arise. In 1956, Eisenhower established a federal-aid program known as the Highway Trust Fund to accelerate the construction of a network of interstate roads. By 1991, the Interstate Highway System in the U.S. consisted of over 42,000 miles of highways. Unlike local roadways, superhighways were designed to bypass large population centers, and were accessible in limited locations at planned entrance and exit interchanges. These highly efficient roadways allow motorists today to travel from one end of the country to the other without having to slow down for intersections and traffic signals.
Research Lab
PEDIAIMPROVE26
Historically, libraries and universities have acted as the primary centers of
research for new ideas and technologies. The growth of private industry in the
modern age has also given birth to hundreds of privately-owned research
facilities. These private laboratories, usually dedicated to research in a
single field related to their founding company, have made tremendous advances
in many fields including physics, biology, chemistry, and medicine. The growth
of privately-funded research has vastly increased the speed at which mankind
achieves new advances in science and technology.
SAM Missile Battery
PEDIAIMPROVE27
The use of airplanes in warfare began in earnest during World War I. By the end of World War II, the use of fighter aircraft and bombers was commonplace and the importance of air warfare continued to grow, as did the importance of effective anti-aircraft defenses. During the 1950's, the refinement of rocket technology allowed for the construction of compact missiles which were used to deliver explosive warheads to their targets swiftly and accurately. Batteries of surface-to-air missiles, or SAMs, were built to protect cities and ground installations against airborne attacks. The long range and high accuracy of SAM batteries provided a much more effective defense than the anti-aircraft guns of World War II.
Coastal Fortress
PEDIAIMPROVE28
The construction of defensive structures such as city walls and fortified castles dates back to ancient times. City walls were designed primarily to repel an attack launched by ground-based forces, and they performed adequately in such a situation. However, coastal cities were also vulnerable to attack from sea bombardments, since even a city wall left sea ports relatively unprotected. The best way to protect the port was to keep the enemy out of range of the city. This was accomplished by constructing fortresses to cover the approach to the city. These coastal fortresses, built at the mouth of the city's harbor or on barrier islands, would hold enemy vessels at bay, turning away or thinning out the attacking force and minimizing damage to the city's port.
Solar Plant
PEDIAIMPROVE29
One of the greatest natural sources of energy available on Earth is the sun. Solar energy can be converted directly into electrical power without the need for mechanical generators through the use of photoelectric cells. Alternatively, large solar collectors known as heliostats can be used to focus solar energy into a water boiler, generating steam to run conventional electrical turbines. Unfortunately, at our current level of technology, both of these systems are prohibitively expensive to construct. However, because of the dwindling supply of fossil fuels and increasing concern over the pollution produced by conventional and nuclear power plants, scientists are constantly working on a viable way to harness the clean and endless supply of energy provided by our sun.
Harbor
PEDIAIMPROVE30
Just because a city is built in a coastal region doesn't guarantee that the city is readily accessible by ship. In order for a port city to establish a steady trade, fishing, or other shipping industry, the city must have a harbor. A harbor is a protected body of water that opens into an ocean or lake that shelters ships from waves and high winds. Although some coastal cities are established in areas where a natural harbor exists, most seaports are forced either to improve the existing natural harbor, or to build a man-made harbor to shelter ships and provide channels deep enough to accommodate large vessels.
Offshore Platform
PEDIAIMPROVE31
Mankind's dependence on wood and coal as a main source of fuel ended when the first commercial oil well went into production in Pennsylvania in 1859. Crude oil could be refined into many different byproducts, and soon replaced wood and coal in many parts of the world. The growing dependence on oil caused the petroleum industry to grow rapidly and wells were drilled all over the world. Most wells were initially drilled on land, but after World War II it was found that many of the largest oil deposits could be found below the sea floor. Shallow water drilling from platforms supported by pylons resting on the seabed proved very successful. Today, large floating platforms can drill for oil at water depths of more than 3300 feet.
Airport
PEDIAIMPROVE32
Since the middle of the 20th century, the airplane has been one of the chief means of long-distance transport in the world. Nearly every major metropolitan area today has at least one airport, with facilities to handle passengers and ticketing, as well as facilities for refueling and repairing the aircraft that land there. Beginning in the 1940's, the growing role of airplanes as combat vehicles led to the widespread construction of military air bases. Nearly 400 of these facilities in the U.S. alone act as bases and maintenance facilities for aircraft assigned to all branches of the military.
Police Station
PEDIAIMPROVE33
The concept of a police force operating independently of the military goes
back to the Praetorian Guard of ancient Rome. In the Middle Ages, noblemen
protected their estates by appointing constables to enforce the law and to
arrest and guard criminals, but the first modern, organized police force was
the London Metropolitan Police. Established in 1829, this organization became
the model for law enforcement organizations in the United States and many
other industrialized nations around the world. The presence of a police force
serves to uphold the laws of society and to control civil unrest. A strong,
visible police force strengthens confidence of the community by keeping the
citizens safe.
Port Facility
PEDIAIMPROVE34
Seagoing vessels have been used for both commercial transport and military purposes for thousands of years. Cities built on rivers and on the coasts of seas and oceans built facilities to receive cargo and to house military vessels stationed in the area. Many of the larger cities built large port facilities that included shipyards for the construction of new vessels, large warehouse and docking facilities, and dry-docks for the repair of damaged vessels. Heavily damaged ships can be repaired much more quickly when such facilities are available.
SS Structural
PEDIAIMPROVE35
The structural parts of a spaceship are the frame to which all other parts of the spaceship are attached. All spaceship components and modules must be connected to a structural section in order to function. Components and modules not connected to the frame are outlined in red on the spaceship display.
SS Component
PEDIAIMPROVE36
Spaceship components provide the motive power of a spaceship. There are two types: propulsion and fuel. Propulsion components are the spaceship engines, and each fuel component provides enough fuel to run one engine. Every propulsion component requires a fuel component in order to function. At minimum, a spaceship requires one of each type of component. The more engines the spaceship possesses, the faster it will arrive at its destination.
SS Module
PEDIAIMPROVE37
Modules are the central components of a spaceship. There are three types: habitation, life support, and solar panels. Each habitation module provides living space for 10,000 colonists. Each life support module provides enough food, water, and other basic requirements to support the colonists in one habitation module. Both habitation and life support modules require power in order to operate, and each solar panel module provides enough energy to run two other modules. At minimum, every spaceship requires one of each type of module in order to be successful in its mission.
Capitalization
PEDIAIMPROVE38
In the business world, companies often need large amounts of cash in order to meet expenses, update facilities, or expand their operations. When there are insufficient funds available to fulfill these needs, these corporations often resort to capitalization in order to raise money. This process involves the sale of a portion of the company's liquid assets. Liquid assets are assets that can be easily converted into cash. These can include surplus raw materials and finished goods, as well as stocks and bonds. The sale of these assets provides the infusion of money needed to meet the company's current needs.
Pyramids
PEDIAIMPROVE39
Built by the fourth dynasty of Egyptian rulers, the Pyramids represent the pinnacle of ancient Egyptian cultural achievement. Constructed on the Giza plateau outside modern-day Cairo, these structures were burial tombs and monuments for the Pharaohs, and may have taken generations and tens of thousands of workers to complete. The Pyramids are the only one of the generally accepted man-made wonders of the ancient world that remain in existence today.
Hanging Gardens
PEDIAIMPROVE40
The Hanging Gardens were a distinctive feature of ancient Babylon. They were a great source of pride to the people, and were often described in accounts written by visitors to the city. Possibly built by King Nebuchadnezzar II in 600 BC, the gardens are believed to have been a remarkable feat of engineering: an ascending series of tiered gardens containing all manner of trees, shrubs, and vines. The gardens were said to have looked like a large green mountain constructed of mud bricks, rising from the center of the city.
Colossus
PEDIAIMPROVE41
The Colossus of Rhodes was a bronze statue of Helios, the Greek God of the Sun, erected near the mouth of the city harbor. It stood over 100 feet high, about two-thirds the height of the Statue of Liberty. Unfortunately, it was toppled by an earthquake only 56 years after its construction. Taking the counsel of an oracle, the city elected to leave the statue where it lay. For over 900 years, people from all over the ancient world came to Rhodes to see the Colossus. It remained where it was until 654 AD when the Muslims who plundered the city sold the statue for scrap.
Lighthouse
PEDIAIMPROVE42
The Pharos was a marble watch tower and lighthouse built in 280 BC on an island in the harbor of Alexandria, Egypt. Estimated to have been 300 feet high, the primary function of the lighthouse was to guide approaching ships to the harbor on an otherwise unmarked coast. Historians debate whether fires were burned on the top of the tower, or whether mirrors were used to reflect sunlight. Since ships rarely sailed along coasts at night, there was probably little need for the lighthouse after dark. The Pharos was destroyed in the 14th century, after having been damaged by several earthquakes.
Great Library
PEDIAIMPROVE43
The Great Library of Alexandria was one of the two most important libraries of the ancient world. It was founded around 300 BC by Ptolemy I, and was enhanced and expanded by his successors. The library attempted to obtain copies of all scrolls of any consequence, and eventually contained over 700,000 volumes. The library was destroyed by religious fanatics in 391 AD, after nearly 700 years of operation. During this period, Alexandria served as the cultural center of the Hellenistic world. Today, only part of the catalog remains, providing us with a mere hint of what treasures the library contained.
Oracle
PEDIAIMPROVE44
In ancient Greek religion, an oracle was a priest or priestess through whom the gods spoke in response to questions. The oracle interpreted dreams, the actions of entranced persons, and physical signs found in the entrails of sacrificed animals. The most famous oracle resided in the shrine of Apollo at Delphi, located on the slopes of Mount Parnassus. This oracle was consulted for centuries by Greeks, Romans, and others about public policy and private matters. A priestess called the Pythia would, for a fee, make public predictions for the future. These ecstatic pronouncements became infamous for their ambiguity.
Great Wall
PEDIAIMPROVE45
The Great Wall of China, a huge stone structure stretching from the Yellow Sea to the Asian deserts, was built over a period of approximately 1,800 years. The wall is 25 feet high and 12 feet thick, and runs nearly 1,500 miles across northern China. The purpose of the Great Wall was to make it difficult for raiders to escape with their booty, and thereby discourage invasion. Despite its overwhelming size, the wall was not intended to keep invaders out, since manning such a defensive structure would have been prohibitively expensive.
Sun Tzu's War Academy
PEDIAIMPROVE46
One of the earliest pieces of military literature is "The Art of War", written by Chinese general Sun Tzu in the 6th century BC. This book contained a detailed explanation and analysis of the Chinese military, from weapons and strategy to rank and discipline. Sun Tzu also stressed the importance of intelligence operatives and espionage to the war effort. Because Sun Tzu has long been considered to be one of history's finest military tacticians and analysts, his teachings and strategies formed the basis of advanced military training for centuries to come.
King Richard's Crusade
PEDIAIMPROVE47
The Crusades were a series of military expeditions by European Christians between 1095 and 1270 AD intended to recapture the Christian Holy Land from Muslim control. The most successful was the Third Crusade, in which a tremendous force led by King Richard I and Philip Augustus managed to regain control over a number of cities along the Mediterranean coast and reconstitute the Latin Kingdom in Palestine. In addition to their more altruistic goals, the Crusades also served to extend the political and religious power of the Pope over a larger area of the world. This great burst of territorial expansion led to an increase in both the population and the productivity of Europe. The ongoing wars provided lucrative business for Western European traders and merchants.
Marco Polo's Embassy
PEDIAIMPROVE48
Marco Polo was a trader, writer, and world traveler who lived in the late 13th and early 14th century. Starting as a young boy, he began traveling with his father and uncle, who were merchants and traders in Venice, along a route that would take him throughout Europe, the Middle East, and Asia. Throughout his life, he visited many places bringing back detailed information concerning lands that no European before him had visited. Polo's book, "The Travels of Marco Polo", was the only existing source of reliable information on such exotic locales as Siam, Japan, Java, Tibet, and India that existed in medieval Europe.
Michelangelo's Chapel
PEDIAIMPROVE49
The beauty of Rome's Sistine Chapel has long served as a testament to the mixture of strong religious beliefs and the love of art shared by the people of Renaissance Europe. Michelangelo devoted four years to painting the mural that adorns the ceiling, a work depicting events in the book of Genesis and other Biblical stories. Few visitors to the Sistine Chapel have failed to be moved by the artist's dedication to his subject, or his feeling for the nature of human struggle, suffering, and spiritual triumph.
Copernicus' Observatory
PEDIAIMPROVE50
Ancient astronomers originally put forth the theory that the Sun was the center of our solar system, and that the planets revolve around it. This knowledge was lost during the Dark Ages, but was re-introduced in the early 16th Century by Nicholas Copernicus. Copernicus' research and theories form the foundation for modern astronomy. Copernicus collected his data from his observatory, a small room in the spire of an East Prussian cathedral. His research methods and observations also marked the rebirth of the scientific method, and were an important step in the advance of knowledge.
Magellan's Expedition
PEDIAIMPROVE51
In 1519, Ferdinand Magellan sailed from Spain with the intention was to reach the spice-rich Malouccas Islands of Indonesia by sailing west, instead of east. Although Magellan himself was killed by natives in the Philippines, his expedition went on to prove conclusively that the world was round. More importantly, it proved that the Americas were indeed a New World. Magellan's expedition was one of the great sea voyages of history, and it inspired further expeditions by other explorers. The discoveries made along the way reduced the dangers to all the sea expeditions that followed.
Shakespeare's Theater
PEDIAIMPROVE52
Most of the plays of William Shakespeare were first performed on the stage of London's Globe Theatre during the 1600s. Theater offered people a diversion from their everyday lives by allowing them to enjoy comedies, tragedies, and triumphs acted out on stage. Similar theaters, such as the Comedie Francaise in Paris, and La Scala in Milan, fulfilled similar roles by offering entertainment to the citizens of their cities. Although the original Globe Theatre burned down, Shakespeare's plays are still performed in a new theater bearing his name, and in other theaters throughout the world.
Da Vinci's Workshop
PEDIAIMPROVE53
Leonardo da Vinci was one of the most celebrated painters of the Italian Renaissance. His most famous works include the "Mona Lisa" and "The Last Supper". Although best known for his art, da Vinci was also an accomplished observer and designer. Preserved in his sketch books are ideas for dozens of inventions, many of them centuries ahead of their time. These include designs for such devices as draw bridges, construction equipment, parachutes, and even helicopters. His scientific and technical drawings became the basis for the development of many of these modern devices.
J.S. Bach's Cathedral
PEDIAIMPROVE54
Few composers were more prolific or beloved than Johann Sebastian Bach. Bach, the most well-known member of a gifted family of German musicians, was perhaps the finest composer of the baroque style of music. In his time, he wrote numerous choral and orchestral pieces. During his lifetime, he was renowned as an organist and music director of St. Thomas' Church in Leipzig, and many of his compositions were religious in nature. After his death, Bach's music gained worldwide appreciation.
Isaac Newton's College
PEDIAIMPROVE55
Sir Isaac Newton, a mathematician and physicist, is considered to be one of the greatest scientists of all time. He is credited with many important discoveries including the laws of gravity, the color spectrum of light, calculus, fluid dynamics, and an understanding of ocean tides. He also built the world's first reflecting telescope. For 32 years, he held an important teaching post at Cambridge University, where he continued his own research while instructing a generation of students.
Adam Smith's Trading Co.
PEDIAIMPROVE56
Adam Smith is generally regarded as the father of modern economics. In his book "The Wealth of Nations", he analyzed the economic processes of supply and demand, and discussed how free trade and individual ambition would lead to both economic and social growth. Smith favored a political environment where the government would only become involved in business and trade to preserve justice and order. Smith's ideas of economics and the lack of government involvement form the basis of modern economic liberalism.
Darwin's Voyage
PEDIAIMPROVE57
Charles Darwin, the main proponent of the theory of evolution based on natural selection, built up much of his evidence for this theory during a five-year voyage around the world. His voyage aboard the H.M.S. Beagle was instrumental not only in the establishment of his theory, but also in the application of the scientific method to the study of nature. Darwin published his theory of evolution in his book "The Origin of the Species". His studies were so thorough that the scientific world never challenged his findings. However, his findings were, and continue to be, challenged on philosophical and religious grounds. Darwin's research opened many new lines of inquiry, and inspired a wave of new biological research.
The Statue of Liberty
PEDIAIMPROVE58
The Statue of Liberty is one of the largest statues in the world. Measuring over 300 feet tall from the base of her pedestal, the statue was originally constructed of copper plating over an iron framework and weighs over 250 metric tons. Designed by French sculptor Frederic Bartholdi, the statue with her upraised torch and the broken chains of tyranny at her feet, was presented to the United States by the French government in 1886 to commemorate 100 years of American independence. The statue itself, Liberty Island, and nearby Ellis Island became a national monument in 1924. For more than a century, the Statue of Liberty has stood at the mouth of the New York harbor. Often the first sight seen by immigrants arriving in America, Lady Liberty symbolizes the ideals of freedom upon which the United States was founded.
The Eiffel Tower
PEDIAIMPROVE59
The Eiffel Tower is one of the world's most famous landmarks. Built for the Universal Exposition of 1889, the tower rises 984 feet above Paris' Champ de Mars, near the Seine River. Structural engineer Alexandre Gustave Eiffel built the tower at a cost of more than $1 million to demonstrate how steel and iron could be utilized in the construction of extremely tall buildings. The tallest building in the world when it was originally built, the Eiffel Tower drew crowds of awestruck observers from around the world. Today, it remains one of Paris' leading tourist attractions.
Hoover Dam
PEDIAIMPROVE61
For centuries, mankind has been harnessing the power of rivers to move waterwheels for various purposes. With the advent of electrical power, it was found the rivers were also very useful for generating electricity. Hydroelectric power plants derive power from rivers by constructing dams to ensure a dependable supply of water. The overflow is then released through special chambers where the moving water turns giant turbines, generating electricity. When planned and engineered properly, this system provides an excellent power source with very limited environmental impact. The Hoover Dam, constructed on the Colorado River near Las Vegas, was one of the earliest hydroelectric power plants.
Women's Suffrage
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After decades of struggle, women in the United States won the right to vote in 1920 with the passage of the 19th Amendment to the U.S. Constitution. The achievement of women's suffrage was accelerated by the excellent record of women working in jobs traditionally held by men during World War I. Full voting rights were granted to women in Great Britain in 1928. Since that time, women have gained the right to vote in most countries in the developed world.
Manhattan Project
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The Manhattan Project was the code name for an intensive and costly research effort during World War II that resulted in the development of atomic weapons. The first two such weapons, the bombs dropped on Nagasaki and Hiroshima in 1945, brought an end to the second World War. For a short time, the United States held a monopoly on atomic weapons. However, by 1949 the Soviet Union had also developed similar technology, based in part on Manhattan Project information obtained through espionage. The nuclear standoff that has resulted from this balance of power may be largely responsible for the absence of major wars since World War II.
United Nations
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Established following World War II, the United Nations is an international organization dedicated to promoting world peace and security. The U.N. also attempts to achieve international cooperation in solving world problems concerning the environment, economics, and cultural issues. Although its peace keeping role is not always entirely successful, it has remained an effective forum for debate where all nations can voice their concerns on matters of worldwide importance.
Apollo Program
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The Apollo Program was begun by the United States in the late 1960s. Following the success of the manned orbital missions of the Mercury and Gemini missions, the destination of the Apollo program was the moon. The early Apollo flights concentrated on orbital observations of the moon, and testing the docking systems of the Apollo craft. The ultimate goal of the Apollo Program was accomplished by Apollo 11 on July 20, 1969, when Neil Armstrong became the first human to walk on the moon. Several other landings followed, the last being Apollo 17 in December, 1972. The Apollo program truly represented a "giant leap for mankind". The U.S. manned lunar missions are unparalleled feats in space exploration, and the technology originally developed for the Apollo Program was later found to be invaluable in designing future space vehicles and orbital platforms.
SETI Program
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The Search for Extraterrestrial Intelligence (SETI) was officially initiated by the United States in the latter half of the 20th Century. The purpose of the program was to find some sort of conclusive evidence that intelligent life existed beyond the confines of our planet. Employing banks of radio-telescopes and other detection equipment, SETI scans the skies hoping to find proof of extraterrestrial life in the form of radio transmissions and other activity. Although the program has yet to find such proof, the effort has produced many useful benefits to astronomy, telecommunications, and other high-tech fields.
Cure for Cancer
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Despite the huge outlays of cash for research and study, cancer still looms as a terrifying and deadly plague on the human race. Although scientists and doctors have discovered many different forms of cancer, and have identified some of the factors that can trigger the disease, a true cure still eludes modern medical science. A cure for cancer would put an end to the source of much suffering and anguish, and allow millions of people, who would otherwise be doomed, to lead happy and productive lives.
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Deserts are arid stretches of land characterized by an annual rainfall of less than ten inches. Adding to the dry environment is the fact that, because the desert atmosphere has such low humidity, evaporation of moisture from the ground exceeds precipitation. Many deserts are characterized by extremely high daytime temperatures and equally low night time temperatures. Only the hardiest plants and animals can survive in the harsh desert environment. Despite the perception that deserts are composed of useless sand, most desert soil is naturally fertile because little water moves through the desert to carry away nutrients. Through the use of artificial irrigation, humans have managed to grow crops in desert environments. If this is not done carefully, it can lead to irreversible environmental damage when the meager water supply that is tapped for the irrigation process is depleted.
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Plains are vast, open tracts of land, usually with very few trees and covered with vegetation such as sage brush and various grasses. Plains are similar to grasslands, except that the topsoil is often not as well suited for growing food. Often, rich deposits of minerals are also found in plains regions. The indigenous plants of the plains makes them well suited for grazing. Large herds of buffalo and other animals can often be found roaming the area. With the proper irrigation, plains can be easily cultivated into adequate farmland for the production of grains and the raising of livestock.
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The areas of land between desert regions and forests in temperate and tropical climates usually consist of grasslands. These fertile regions, covered with various types of vegetation, once occupied large areas of North and South America, Africa, and Eurasia. These areas are characterized by marked wet and dry seasons, with annual periods of drought. Although many grasslands are naturally occurring, grasslands can also be created through deforestation of woodland areas. Grasslands are often cultivated and used as pastures and grazing lands. Because of the relatively low rainfall in these regions, the topsoil is high in nutrients. Grasslands are, therefore, well suited for growing crops, especially grain crops.
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Extensive areas of land covered by a thick growth of trees and related ground vegetation are classified as forests. There are several different types of forest, determined primarily by climate and the type of vegetation they contain. Forests of some type exist on nearly every continent in the world. Forests are a valuable source of natural resources, providing wood for paper products, building, and other purposes. The harvesting of trees must be done carefully, however. If not done in moderation, lumbering can destroy the natural habitat for indigenous animal species, and destroy the ecology of the land. Government regulations limiting the amount of trees that can be cut, and requiring the lumber industry to plant new trees to replace what they have harvested, help to prevent major ecological damage as a result of deforestation.
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Rolling areas of the countryside, often found between plains and more mountainous regions are known as hills, or foothills. These areas, often covered with rich soil and grasses or heavily forested, are rich in resources. Coal, iron, lead, copper, and even gold and silver may be found in these regions, making them profitable areas for the mining industry. In areas where the below-ground resources are scarce, hill areas are often cultivated for agricultural purposes. Certain crops such as coffee and grapes thrive in these regions, given the proper climate.
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Mountains are areas of high elevation, usually consisting of a chain of rugged peaks and valleys. Most mountains are formed when the plates making up the Earth's crust impact or slide against one another, raising layers of rock above the surrounding land. Mountains can also be formed by volcanic action, or through the effects of erosion. Although generally poor agricultural regions, mountains are often a source of great mineral wealth, with large deposits of gold and other valuable ores. Aside from their economic value, mountains provide a natural defensive barrier, shielding human settlements from invaders. Extensive mountain ranges can also greatly affect the weather patterns of a region by blocking and diverting wind and storms.
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In the far-northern regions of the world, and in isolated regions in the
Antarctic, there are thousands of miles of barren plains known as tundra.
These regions have an extremely low average temperature and a very short
summer season. The primary characteristic of the tundra is a layer of
permanently frozen soil known as permafrost just below the topsoil layer,
which prevents many plants from taking root and making agriculture all but
impossible. Like deserts, the tundra receives little precipitation however,
the flat, frozen ground keeps groundwater from draining, forming bogs where
various grasses, moss, and other simple vegetation can grow. Despite the harsh
environment, a wide variety of animal life flourishes in the tundra, providing
possible sources of food, and providing trade potential for the fur and
trapping industry.
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Glaciers are large masses of ice and snow found in mountain regions, and near the north and south poles of the planet, where the rate at which snow and ice melt is less than the rate of snowfall. There are several varieties of glaciers: alpine and piedmont glaciers, which are formed in the valleys of high mountain regions and ice cap and continental glaciers that may cover large portions of a continent. All glaciers are similar in composition, consisting of upper layers of softer snow and ice crystals, and lower layers of highly compressed, solid ice. Although some glaciers are stationary, some may move anywhere from a few feet to more than 100 feet each day, carving and reshaping the land as they go. Glacial regions are inhospitable, containing little animal life, no plant life, and virtually no resources of any kind.
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Swamps are wetlands which are largely uninhabitable by humans. These areas are usually flooded with water, ranging in depth from a few inches to several feet, due to heavy rainfall and overflow from nearby lakes and rivers. Although inhospitable for human life, swamps are teeming with both animal and plant life. Certain spices and useful substances such as peat, which is used as a fertilizer, can be found in abundance in certain swamp areas. Swampland is often drained, and converted into grassland and plains in order to make it more useful for resource and food production. However, environmental groups have been successful in slowing the destruction of wetlands, and setting up sanctuaries for the wildlife that inhabits these regions.
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In heavily forested areas where rainfall is high, the growth of both trees and
other indigenous plants is profuse. The dense, tangled environment of the
jungle is home to wide varieties of plant and animal life. Although mineral
deposits and fruit-bearing plants can sometimes be found in these regions,
jungles tend to lack both mineral and food resources. This, combined with the
sheer density of the native plant life, makes jungles inhospitable to humans.
In order to make these areas more useful, jungles are often destroyed through
forestation and burning to yield areas of grassland. While this improves the
usefulness of the land for humans, it destroys the habitat of the indigenous
animals of the region. It is estimated that hundreds of undiscovered species
of insect and animal life are made extinct every day as a result of the
destruction of jungles and rain forests.
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The oceans and seas of the world cover almost three-quarters of our planet. They are home to millions of life forms ranging from microscopic plankton to whales, the largest mammals in the world. The animals and plants that inhabit the sea provide an excellent source of food. For centuries, coastal and island cultures have thrived on the resources and easy access to trade provided by the sea. Unfortunately, in many parts of the world, a combination of over-harvesting of marine animals and increased pollution have begun to threaten fragile coastal ecologies. Some species of marine life are seriously threatened. For example, the whaling industry, which thrived in the 19th and early 20th century, is responsible for hunting certain species of whales to near-extinction. Government regulations concerning the dumping of pollutants and the indiscriminate harvesting of marine life are constantly being updated in response to these growing problems.
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In rare instances, underground reservoirs or rivers beneath a desert may run near the surface, forming a lake in the middle of an otherwise barren region of land. The presence of water allows plants to grow, and may even attract animal life. An oasis makes it easier for human settlements to survive in desert climates by providing rich soil for the growing of food crops. Since they are so rare, oases are fiercely guarded by desert dwellers who are lucky enough to stumble across them.
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The plains areas of the world are inhabited by roaming herds of many different varieties of animals. These herd animals have been hunted, both for sport and for food and pelts, throughout history. Some of these animals can even be domesticated and used for farming and other purposes. One of the most widespread herd animals is the buffalo, various species of which are found throughout the world. Bison, commonly referred to as buffalo, were once the most dominant species of the North American plains. Bison were a valuable resource to native American tribes, who hunted the animals as a source of food and pelts. When European settlers began to expand to the west, the bison was hunted to the brink of extinction by thrill-seekers and sports hunters.
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Grassland (shield). Settlements in the sparse tundra regions of the arctic cannot raise crops and domestic animals for food due to the harsh conditions. They are, therefore, much more dependent on the hunting and trapping of local wildlife for food. The many species of birds and small game, as well as larger animals such as elk and caribou, provide a source of food in an environment that is otherwise barren and inhospitable.
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Since ancient times, hunting of game animals has been important both for survival and for sport. Forested areas containing a large concentration of deer, elk, and smaller game were very valuable as a source of food for nearby settlements and cities. Though the widespread practice of farming domestic animals for food purposes has made hunting for sport much more common than hunting for food, certain animals such as geese, ducks, and deer are still frequently hunted and killed for food.
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Coal. More than 300 million years ago, plant life growing in swamps began to decompose. Layers of sand and mud covered the decomposing plants, and the decaying plants were compressed by the combined weight of water and sediment. Over time, the plant matter hardened and became coal. Coal deposits are mined all over the world, and coal was one of the major fuel sources in the world through the 1970's. In many countries, concern over the environmental effects of the burning of coal has led to a decline in its use. The smoke produced by burning coal has a high acid content, and creates an environmental condition known as "acid rain", which is harmful to plant and animal life. Despite the environmental concerns, some of the largest coal mines in the U.S. each still produce more than 450,000 metric tons annually, making coal mining a very profitable industry.
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Gold has always been one of the most highly valued metals in the world. It is used in the manufacture of everything from jewelry to electronics, and has been established as the basis for monetary systems world wide. The factor that makes gold valuable is its rarity. Although gold can be found in many different areas, the most valuable deposits are large veins of gold ore running through mountains. When a large deposit is found, mining the deposit greatly boosts the economy in settlements and cities near the mine. An historical example of this phenomenon are the many towns that grew and prospered over a relatively short time during the California gold rush in America during the 1800's.
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Musk Ox. Settlements in the sparse tundra regions of the arctic cannot raise crops and domestic animals for food due to the harsh conditions. They are, therefore, much more dependent on the hunting and trapping of local wildlife for food. The many species of birds and small game, as well as larger animals such as elk and caribou, provide a source of food in an environment that is otherwise barren and inhospitable.
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Ivory, the hard substance of which elephant tusks are composed, is highly sought for the carving of ornamental objects. Most ivory is obtained from the tusks of African elephants, but other sources include the tusks of walruses and the fossilized tusks of prehistoric elephants and mammoths found in the northern glacial regions of the world. Although importation of ivory has been banned in many countries due to the fact that many of the species from which it is obtained are now endangered, the ivory trade was once a widespread and profitable venture.
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Some bogs and swamps contain a brown organic material known as peat. Peat is
made up of partially decomposed plant matter, and has a high carbon content.
Although dried peat is sometimes compressed and burned as fuel, the most
valuable use for peat is as a fertilizer and mulch for farming and gardening.
The high mineral content and its ability to retain moisture make peat
well-suited to this purpose.
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Gemstones, treasured throughout time for their beauty and value, have always been a sought-after commodity. Most gemstones, such as diamonds, are mined in various areas throughout the world, most notably Africa. Some of the most notable gem deposits, however, have been found in archeological digs. The ruins of ancient civilizations in the jungles of Central and South America have sometimes been found to hide large quantities of precious and semi-precious gems, as well as gold and other items of value. The discovery of such a site can lead to an increase in trade in the areas surrounding the dig, as both professional and amatuer treasure hunters swarm to the region to seek their fortune.
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Prevailing winds, ocean currents, and deep water trenches can often combine to produce conditions that are optimum for fishing. In areas such as the Pacific coast of Central and South America, offshore winds push the warm surface waters out to deeper waters. Underwater currents push cold, nutrient-rich water from deep below the surface back toward the coast. The high concentration of nutrients in this colder water, caused by decomposition of organic matter at extreme depths, creates an ideal environment for fish and other sea life. Civilizations with access to areas such as this can significantly increase their food supply by establishing a thriving fishing industry.
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Oil has been known to humans since ancient times. Oil deposits found on the surface were used for centuries for waterproofing and fuel purposes. But it was not until the coming of the Industrial Revolution that civilization began to form a dependence on petroleum products. The widespread use of oil for fuel, lubrication, and other purposes led to a search for larger supplies. In the mid 1800's, the first oil wells were drilled, marking the beginning of a tremendously important and profitable industry. Today, with the world's oil supplies dwindling and the demand for oil constantly rising, oil is a more valuable resource than ever.
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Wheat has been a staple crop for civilizations occupying temperate zones of the planet since pre-historic times. There is archeological evidence that bread wheat was cultivated in southern Turkestan as early as 6000 BC, though naturally occurring wheat was probably used for food purposes much earlier. Throughout the temperate zones, wheat has become the primary food crop. It is particularly well suited for growth in vast, open plains like those found in the central United States.
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Silk has been a valuable commodity for textiles since its properties were discovered in the 27th century B.C. Silk is obtained from the cocoon of the silkworm moth, which was originally native to the forests of China. The fine fibers of the cocoon is woven into cloth, which is used to make all types of clothing. Raw silk was obtained only from Asia until 550 AD, when two monks sent from the Roman Empire secretly stole silkworm eggs from China and brought them to Europe. Eventually, silkworms were found in many areas throughout the world. Less expensive synthetic fibers of the 20th century led to a decline in the silk market, but silk is still very popular in many types of clothing and other goods.
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Wine, a beverage made from fermented grapes, was first produced as early as 6000 BC Its use spread throughout the Middle East and Egypt, and it quickly became a popular beverage of the ancient world. The grapes used for the making of wine are grown in many different regions of the world. Most vineyards are located in hills and valleys of temperate regions. Wine making as an industry has been perfected over several centuries. Many regions such as the Rhine and Loire valleys of Europe are well known for their fine wines, and derive a significant portion of their economy from wine making.
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When early civilizations began to use metal to construct tools and weapons, the most commonly used metal was bronze. Bronze had the advantage of being readily available and easy to work with. Unfortunately, it was too soft to hold an effective edge. In the mid-14th century in central Europe, iron replaced bronze as the metal of choice, and the Iron Age was begun. Since this time, iron has been a valuable commodity. Deposits of iron and iron ore found in mountains are mined and processed for use in their raw form, and in the production of steel.
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Throughout history, animal furs have been valuable commodities for trade and sale. Many different types of animals including minks, rabbits, and beavers have been captured by trappers for the purpose of obtaining their pelts for use in the making of clothing and other items. The exploration and colonization of the New World caused the fur industry to boom by making a variety of furs readily available. By the late 1800's, farms were set up specifically to raise animals for the fur industry. Starting in the 1970's, environmentalists and animal rights groups have lobbied to change public opinion concerning the harvesting and sale of furs. Despite these vocal groups, the fur industry remains profitable, if not as wide spread, in the world today.
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Certain types of plants have evolved in such a way that they produce mild toxins or repellents that make their odor or flavor distasteful to animals. Oddly enough, many of these plants were sought by humans because of these smells and tastes. A profitable spice trade was begun by merchants in the Middle East before 2000 B.C. Spices are used now, as they were in the ancient world, to preserve food and enhance its flavor. Although spices are now commercially cultivated and prepared, most types can still be found in abundance in nature. Many of the most popular spices, such as cloves and nutmeg, are extracted from plants that grow in tropical or swampy regions of the world.
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The tropical environments that are so conducive to the growth of jungles also provide the perfect environment for growing certain fruits. Bananas, for example, originally native to the jungles of Southeast Asia, are an excellent, naturally occurring food crop. Many such fruits, including the banana, can be transplanted and grown in similar climates all over the world.
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Whaling, the hunting and killing of whales for oil and other byproducts, was practiced as an organized industry as early as 875 AD. By the 16th century, it had risen to be the principle industry in the coastal regions of Spain and France. The industry spread throughout the world, and became increasingly profitable in terms of trade and resources. Some regions of the world's oceans, along the animals' migration routes, had a particularly dense whale population, and became the targets for large concentrations of whaling ships, and the industry continued to grow well into the 20th century. The depletion of some whale species to near extinction led to the banning of whaling in many countries by 1969, and to a worldwide cessation of whaling as an industry in the late 1980's.
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Fed by natural springs, snow melt, and small tributary streams, rivers flow from mountains and other upland sources into larger rivers, lakes, and oceans. Rivers can be found in almost any terrain, from lush jungles and forests to arid desert regions. Since the dawn of civilization, towns and cities have grown up around rivers because the land in river valleys is usually very fertile, and well-suited for farming. In addition, the river provided easy and quick access between towns by boat for trade and travel. Water could be channeled from rivers via aqueducts to cities some distance from the river for the purposes of irrigation. Rivers are also good sources of mineral resources, and can provide power to run machinery and generate electricity.
Advanced Flight
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During World War II and in the years that followed, great leaps were made in the field of aviation. The military demands of the war necessitated the development of aircraft designed for long-range bombing, and for the transportation of troops and equipment. Although advances in aviation were made all over the world during this time, the Germans were particularly adept in the development of advanced flight technologies. In 1944, they developed the V-2 "buzz bomb", the first truly guided missile, capable of delivering 2000 pounds of explosives to targets nearly 200 miles away. The Germans also developed the Me 262, the first jet fighter plane, which was first used in 1945. Although both the V-2 and the Me 262 came too late to affect the outcome of World War II, both of these advances paved the way for the advanced flight technologies of today.
Alphabet
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The ancestors of modern alphabets were the iconographic and ideographic symbols developed by ancient man, such as cuneiform and hieroglyphics. The first known alphabet, a combination of a number of early pictographic symbols known as North Semetic, was developed between 1700 and 1500 BC. Four other alphabets, South Semetic, Canaanite, Aramaic, and Greek, had evolved from the North Semetic alphabet by 1000 BC. The Roman alphabet, used by all the languages of western Europe including English, was derived from the Greek alphabet sometime after 500 BC. The Roman alphabet became one of the most widespread due to the extensive use of the Latin language during the reign of the Roman Empire. The development of alphabets was significant in the development of advanced civilizations because it allowed history and ideas to be written down, rather than memorized and passed along orally.
Amphibious Warfare
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A combined land and sea attack, usually associated with the capture of a beach head or coastal area, is known as amphibious warfare. First attempted by the ancient Persians during the Battle of Marathon in 490 BC, successful coordination of amphibious assaults are considered to be among the most complex military operations. When ship-mounted guns were developed, naval vessels would open fire on ground forces and gun emplacements while merchant ships were used to land troops and supplies. The first modern amphibious assault took place at Gallipoli during World War I. Poorly planned and executed, this assault failed, but served as an example of the need for perfect coordination of forces in this type of attack. As battlefield communications improved, and the range of ship-mounted weapons increased, amphibious warfare became increasingly successful, and played a vital role in World War II. Today, amphibious operations are augmented by fast, armored landing vehichles hovercraft that are capable of moving troops to and across the beach and airborne assistance from planes and helicopters.
Astronomy
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Astronomy originated as simple observation and recording of regular celestial movements for the purpose of time keeping and determining directional bearings. The ancient Greeks were among the first to study astronomy in detail. They described the use of stars for navigation at sea, and recorded the position of constellations during each season of the year for purposes of determining times for planting and harvesting. The Greek astronomer Aristarchus developed the theory that celestial motion could be explained by the fact that the Earth revolved on its axis once every 24 hours, and revolves around the sun along with the other planets. This theory was rejected at the time, only to be rediscovered nearly 2000 years later by Copernicus. These early students of astronomy compiled data that became the cornerstone for modern astronomical research.
Atomic Theory
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Philosophers in ancient Greece were the first to use the term "atom" to describe the smallest possible bit of matter. They hypothesized that all things were made up of atoms, and could be theoretically broken down into atoms. The atom, however, was indestructible. Study of atomic theory proceeded slowly. Experimental scientists of the 16th and 17th centuries developed methods of analyzing gases, liquids, and solids to determine the individual elements of which they were composed. The founder of modern atomic theory was British chemist John Dalton. Dalton's experiments explained how atoms link together to form molecules. He also explained the nature of these chemical bonds, and performed a number of experiments concerning the formation of various chemical compounds.
Automobile
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The earliest attempts at producing a self-propelled vehicle date back to the late 1770s. These early vehicles used bulky steam engines for power. Despite constant improvements, the steam engine ultimately proved impractical for small vehicles. The development of the internal combustion engine in the late 1800s provided a small but powerful replacement for steam engines, and were able to achieve much higher speeds. The first practical automobiles were developed in the late 19th century, by automotive pioneers in France, Germany, and the United States. By the 1920s, a number of automotive manufacturing companies were operating in the U.S., including Ford and General Motors. By 1980, more than 300 million cars and 85 million trucks were in operation throughout the world. The popularity of the automobile has led to massive improvements in the highway systems in most industrialized countries. Unfortunately, automobiles are also one of the primary sources of air pollution, and have resulted in an all time high demand for petrochemical fuels.
Banking
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Many of the services performed by banks today can be traced back to medieval Europe. Certain families, such as the Medicis of Italy, were known for the banking duties they performed. These wealthy merchants pooled their surplus money into a bank, then loaned cash (with interest) to other commercial enterprises. The availability of this capital for investment made many new businesses possible, accelerating economic growth. The first modern banks were established in Europe during the late 1600s. The primary function of today's banking system is the granting of loans to consumers and businesses. In addition to loaning money and safeguarding deposits, banks also invest in government and private securities and bonds. Both the loan and investment functions of banks not only make profits for the bank itself, but stimulate the economy by providing funds for business growth and consumer purchases.
Bridge Building
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Humans have been constructing crude bridges from the first time they laid logs across a stream or river they needed to cross. Although a brick arch bridge is said to have existed in Babylon in 1800 BC, most bridges of this time period were probably made of wood. The Romans developed bridge building to a degree that it took Western medieval engineers many years to match. Roman bridges were often composed of several stone arches which supported a flat road. Bridges of this type date back to as early as 219 BC. It wasn't until the mid-1800s that bridge designs began to incorporate metal for added strength and permanence. Early truss bridges used wooden trusses bound with iron tie-rods. By 1850, wooden trusses gave way to steel. Modern bridges incorporate designs ranging from concrete and steel arches to steel girder and suspension styles. The development of modern bridges constructed of durable materials was vital to the expansion of the worlds railroad and highway systems.
Bronze Working
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Evidence of the use of bronze, an alloy of copper and tin, dates back to Thailand in 4500 BC. Several hundred years later, bronze working was discovered in the Middle East. Artifacts from this period show that bronze was initially used for decorative purposes only. This is because tin was not readily available. It wasn't until approximately 2000 BC, when tin was regularly imported from neighboring regions, that bronze replaced copper in the construction of larger items. Bronze was harder and less brittle than copper, and it held a sharper edge. Tools, weapons, and armor made from bronze were also cheaper to produce and more durable. The period of time when bronze was the metal of choice for such items was known as the Bronze Age. The Bronze Age lasted until iron working became prevalent in approximately 1200 BC.
Ceremonial Burial
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Groping for an explanation of the world around them, the earliest humans developed the first concepts of religion. Gradually, rites of worship grew to include sacrifices, ceremonies, vigils, symbology, sacred items, and prayer. One significant step in the advance of worship was the ceremonial burial, often a ritual preparation of the deceased's body for the afterlife his or her culture anticipated. The remains of ceremonial burials offer some of the most detailed information about past civilizations.
Chemistry
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The earliest practical use of chemical processes were by metal smiths of the ancient world. These artisans learned how to use heat to melt various naturally occurring metals together to form alloys such as bronze. Early manufacturers of cloth also used primitive chemical processes to set dyes. In the following centuries, chemical processes were studied through the pseudo-science of alchemy, which attempted to change base metals into gold. Although alchemists were, of course, unsuccessful, they did develop many valuable chemical processes as a result. The manuscripts produced by alchemists were studied by succeeding generations, and an effective knowledge of chemistry had been accumulated by the late 13th century. In the 17th century, the ideas of alchemy finally died out as an increasing body of true chemical knowledge was gained through experimental analysis, leading to the modern science of chemistry.
Chivalry
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Chivalry was a code of rules governing the behavior of an aristocratic class of warriors known as knights. First appearing in the 12th century, the rules of chivalry governed the not only the knights' behavior in battle, but in their personal lives as well. The chief chivalric virtues of piety, honor, valor, courtesy, chastity, and loyalty represented a fusion of Christian and military morality. A similar code of behavior known as "Bushido" or "the way of the warrior" governed the behavior of the samurai warriors of ancient Japan. Although the strict practice of chivalry had all but disappeared by the 15th century, the ideals of chivalric behavior became the basis for what is now considered to be gentlemanly conduct.
Code of Laws
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The earliest tribal civilizations were bonded together by mutual needs and beliefs. These groups were ruled by a tribal chieftain, who acted as an advisor, and enforcer of the will of the gods. No formal laws existed in these early cultures, but fear of the gods and a sense of tribal customs and morality kept order in the tribe. As societies became larger and more diverse, the need arose for established rules of conduct. The earliest known codes of laws existed in Babylon, India, and Palestine. The Twelve Tables of Rome, written in 500 BC, and its successors such as the Justinian Code, were the first codes of law to distinguish between public law, which involves the state, and private law, which concerns disputes between citizens. Roman law was the first formalized written system of laws, and went on to influence many of the legal systems of the modern world.
Combined Arms
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Advanced flight technology, combined with the principles of amphibious warfare and mobile warfare, represent the potential for a devastating attack force. Combined air, sea, and ground assaults played a vital role in World War II. The Allied invasion of Normandy in June 1944 represented such an attack. Bombers and fighters were deployed over the target area to claim the skies, while naval vessels sat off the coast and bombarded the beach head. Transports then landed troops and equipment on the beach to begin a ground assault. Modern advances make today's combined assaults even more effective. Naval vessels and stealth aircraft equipped with cruise missiles and smart bombs soften enemy resistance before a ground assault. Helicopters drop and retrieve soldiers behind enemy lines in places not accessible to fixed-wing aircraft. Powerful armored tanks, such as the M1, can be quickly deployed, moving at speeds up to 60 miles per hour. Finally, the combined assault is coordinated through a network of sophisticated communcation, targeting, and detection devices, allowing more precise deployment of forces than previously possible in history.
Combustion
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The development of the internal combustion was a great advance of the Industrial Age. The forerunner of today's internal combustion engine was built in 1876 by German engineer Nikolaus Otto. Refinements on Otto's design over the next ten years led to more efficient and powerful engines. The internal combustion engine forever changed world transportation. Early automobiles utilizing steam engines had proven to be both under-powered and impractical, but the fuel efficiency and compact size of the internal combustion engine allowed the automotive industry to flourish. Several variations, including the diesel engine designed by Rudolf Christian Karl Diesel, went on to revolutionize propulsion in shipping and other transportation industries.
Communism
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Communism is a conceptualized system of government in which resources and production facilities are the property of the entire society rather than individuals. In a communist society, labor is shared equally as well, and the benefits of labor are distributed according to need. Under such a system, all people would be equal, without class stratification. Although the basic idea of communism has existed since the time of Plato, modern communism is identified with the system of government described by Karl Marx and Fredrich Engels in the "Communist Manefesto". They believed that capitalistic systems, in which the rich upper class prospered through the exploitation of the powerless lower class, were bound to destroy themselves. At this point, the poor would rebel against their former opressors and form a classless society. This prophecy has never come true, and countries who have attempted to base their governments on communism have ultimately failed to achieve the utopia described by Marx and Engels.
Computers
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A computer is a device capable of performing a series of repetitive arithmetic
or logical functions far more quickly than the human brain. The earliest
computers were designed to solve complex mathematical equations. British
mathematician Charles Babbage conceived such a machine, called the Analytical
Engine, in the 19th century. Many variations of analog, or mechanical,
computing devices were built during the first half of the 20th century, and
were used for such tasks as computing torpedo tracking in submarines and
controlling bombsights. The growing study of electronics in the late 1940's
led to the invention of the digital computer. The first all-electronic
computer, containing 18,000 vacuum tubes and capable of hundreds of
multiplications per minute, was built in 1946. Continuous advances in
electronics since this landmark event rapidly reduced the size and increased
the speed and efficiency of computers. Today, computers are commonplace, and
are used in virtually every field of endeavor. Significant advances in
computer technology continue to take place at an amazing pace.
Conscription
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Compulsory enrollment in the armed forces has been practiced for thousands of years. In ancient Greece, befroe the introduction of a professional militia in about 2000 BC, men between the ages of 17 and 60 were obligated to serve in a civilian militia. The modern form of conscription was introduced in France during the Revolution in 1789. By the 19th century, nearly every country except for Great Britain and the United States had instituted a program of peacetime conscription. Many of the combatants in both World Wars fought with forces composed largely of conscripted troops. The U.S. Selective Service Act of 1948 maintained peacetime conscription following World War II. This act, which was to have expired in 1950, was extended due to the Korean War. Peacetime conscription in the United States continued until 1973, at which time military service became voluntary.
Construction
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The development of masonry led to a widespread use of stone in simple structures such as fortifications, but due to the weight and cumbersome nature of stone blocks, more complex structures had to be made of simpler materials. The need for the widespread use of more durable and permanent materials eventually became apparent, forcing ancient artisans to learn new techniques. The biggest problem to overcome was finding a stable way to span the distance between two upright columns or walls using stone blocks. To solve this problem, fundamental architectural elements such as the arch and vault evolved. These basic construction techniques allowed larger and more elaborate buildings to be created from stone and mortar. Many of the buildings erected by these early builders are still standing, a testament to the sound construction techniques employed in their construction.
Corporation
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As businesses grow, they often find it necessary to raise large amounts of operating capital in order to expand their operations beyond a certain point, or to meet operating expenses. In these cases, one option available is to form a corporation and "go public", or sell shares of the business to investors. This arrangement allows the business to expand rapidly, while spreading the risks of the expansion among many people, reducing individual risk. Corporations also have legal advantages such as the right to sue, and the limitation of liability for the corporation's debt to the amount originally invested by the owners. Corporations as legal entities have existed since ancient Rome, although the joint-stock company as it is known today didn't begin operating until sometime in the 16th century.
Currency
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As cities grew, their internal economies became more complicated. People became specialists, some primarily producing grain, some pottery, some bricks, etc. A system of barter developed, so that one individual's wares and services could be exchanged for those of another. Gold and silver were widely used in such transactions, but the pieces needed to be weighed and tested for purity each time they changed hands. In 600 BC, the Lydians found a way around this problem. They began the practice of shaping electrum, an alloy of gold and silver, into pieces of predetermined weight and purity, stamped with an official symbol. This idea caught on, and within 50 years all the important trading centers of the world had adopted similar practices. The widespread use of currency created universal standards of value, allowing people from various societies to conduct business almost anywhere without being forced to bring along bulky goods for trade and barter.
The Democracy
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Democracy is a ruling system where the citizens have a great deal of control over the actions of the government, either directly or through elected representatives. Democratic governments can be traced back to the city-states of ancient Greece and Rome. Citizens would gather in a public forum, and each one would have the opportunity to speak and vote on issues affecting the community. This direct democracy system was possible due to the relatively small populations of the city-states. Starting in the 17th century, the monarchs of Europe began to be stripped of their absolute power, and by the end of the 19th century the citizens had a strong voice in government in many European nations. Large populations made public forums impractical, so the people elected groups of representatives to carry their views to the ruling powers. Strictly speaking, this type of system more closely resembles a republican system rather than a true democracy. This type of representative democracy is considered the best governing system in the modern world because of the personal and economic freedom enjoyed by the citizens.
Economics
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The ideas of supply and demand, and philosophies concerning trade and the production and consumption of goods and services, are concepts that have existed since the dawn of mankind. As societies became more complex, however, people began to study these abstract concepts in a more formal way. The first recorded study of economics as a science, rather than a philosophical or political concept, was the book "The Wealth of Nations" by Scottish economist Adam Smith. This book represents the first attempt to fully analyze sources of income and the distribution of wealth. Smith's analysis of economics served as a guide by which many of the governmental economic policies of the present day were formed.
Electricity
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The phenomenon of electricity in the forms of lightning, static electricity, and magnetism has been witnessed by humans since the dawn of time. Electricity was not seriously studied, however, until the 17th century. Early electrical pioneers studied various electrical phenomena, and built devices both to generate and to measure electrical charges. In 1892, the electron theory was advanced by Hendrik Antoon Lorentz, a Dutch physicist. This theory, which explains electricity as a reaction between positively and negatively charged electrons, formed the basis for modern electrical theory. Based on Lorentz's work, early engineers such as Thomas Edison pioneered methods allowing the widespread use of electricity as a power source.
Electronics
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The field of electronics deals with the practical application and manipulation of electricity and electromagnetic phenomena. The invention of the vacuum tube in the early 20th century marked the beginning of modern electronics. The vacuum tube was capable of amplifying weak radio signals, allowing them to be transmitted over greater distances. Vacuum tubes also allowed music and voice to be superimposed onto radio waves for transmission. The early study of electronics revolutionized a number of fields, especially the field of communications. Because of the vacuum tube, the technology of radio communications was highly developed by World War II. After the war, electronics research continued to advance rapidly. Post-war advances include the earliest examples of digital computers and, eventually, transistors and integrated circuits: miniaturized replacements for the vacuum tube.
Engineering
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Engineering is the application of scientific and mathematical principles to the design and/or manufacture of theoretical systems and physical objects. Prior to the mid-18th century, all engineering functions were carried out by military engineers. Their work involved the construction of roads, bridges, fortifications, and the performance of other duties relating to the military. In the late 18th century, civil engineers took over all nonmilitary engineering functions. Other fields of engineering prior to the 20th century included mining engineers, who designed mines and methods of mining, and mechanical engineers, who dealt with the design and construction of machinery. As new technologies developed, new fields of engineering developed along with them. Today, there are engineers specifically trained in nearly every field, from electronics and computers to chemistry and atomics.
Environmentalism
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For centuries, human society has taken the gifts of nature for granted. As civilization grew, humans spread out across the face of the planet, taking what they needed from the land and producing more and more waste materials with little regard for the future. In the late 1960's, a growing number of people became concerned about the growing problems of pollution and the destruction of natural habitats. This movement led to the formation of groups like the Environmental Protection Agency (EPA). The EPA's aim is to reduce all types of pollution. To this end, the agency has imposed strict laws and guidelines concerning the disposal of hazardous materials, set clean water standards, and studied more effective techniques of solid waste disposal. The primary goal of the environmental movement as a whole is to make sure that the environment is safe and intact for future generations to enjoy.
Espionage
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As far back as 500 BC, the Chinese military strategist Sun Tzu stressed the importance of the gathering of covert information about one's enemy. Although every world government has strict laws and penalties to deal with spies, covert intelligence is an important political, technological, and military commodity. During times of war, covert operatives provide important information about enemy troop movements and weapons technology. Spies may also be called upon to perform acts of sabotage in order to delay or divert the enemy. In peacetime, organizations such as the CIA use operatives to keep track of potential political situations abroad. Spying is not limited to politics and war industrial spies are often used to gain information about rival companies.
Explosives
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An explosive is a chemical compound or mixture that undergoes rapid combustion
and produces heat, gas, and pressure effects. The earliest explosive compound
known was gunpowder, which was first used in the13th century, and was the only
explosive known for hundreds of years. The first modern explosive, a compound
known as nitroglycerin, was discovered in 1846. Compounds similar to
nitroglycerin are the most commonly used explosives today. Explosives vary in
brisance, or shattering effect, and in their stability under various
environmental conditions. Aside from their obvious use in weaponry, explosives
are also used in such peaceful applications as rocket propellants and for
mining and demolition work.
Feudalism
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In the unsettled times following the collapse of Charlemagne's Frankish empire, a new social and political system arose in Europe called feudalism. Derived from the concept of monarchy, feudalism was a hierarchical system in which each descending stratum owed allegiance to those above. The king, whose authority was second only to God, granted tracts of land, or fiefs, to his barons. The barons might then grant smaller estates to knights, who swore to protect and serve the baron. The knights, in turn, might then grant fractions of their fiefs to subordinates who would serve the knights. At the bottom of the feudal pyramid were the serfs, who could not own land, and acted essentially as slave laborers who worked the land for their masters. Feudalism began to decline in the 13th century, when standing armies and mercenaries began to fulfill the protective role once served by the vassals and knights.
Flight
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The idea of flight has tantalized humans since the dawn of time. Studies regarding the possibility of producing a flying machine date back to the 13th century. In the 16th century, Leonardo da Vinci proposed a number of inventions that eventually came to pass, including the propeller and the parachute. Throughout the 19th century, various engineers experimented successfully with gliders, and experiments with compressed air and steam engines attempted to produce self-powered flight with limited success. The key to success in powered flight was the invention of the internal combustion engine. Just after the turn of the 20th century, Orville and Wilbur Wright made the first four controlled, sustained human flights at Kitty Hawk, N.C. The technology of flight advanced rapidly from this landmark event, and within a relatively few years, aircraft were circling the globe, safely delivering passengers and mail at record speeds.
Fundamentalism
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Fundamentalism is a governing system whose laws and doctrines are rooted in the extremist and controversial views of religion. Fundamentalists believe in the absolute truth and infallibility of their religion, accepting nothing short of a literal interpretation of the scriptures of their faith. Their views are sometimes so radical as to put them at odds with even the most devout traditionalists of the religion in question. Fundamentalist movements have appeared from time to time throughout the world, including a widespread movement of Christian fundamentalism in the U.S. in the early 20th century. In some cases, most notably in areas of the Middle East, these movements are so widespread that entire nations fall under Fundamentalist rule. Such governments, backed by a fanatical military force, can be a serious threat to any country that opposes their radical views.
Fusion Power
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Nuclear Fusion is the process by which two atomic nuclei combine to form one
heavier atomic nucleus, giving off tremendous energy as a by-product. This
type of nuclear reaction, which is the process by which stars such as the sun
produce heat and light, requires very high temperatures and an enormous amount
of pressure to initiate, and a reliable system of fuel containment to sustain.
Fusion reactions have been produced in artificial environments on Earth by
bombarding deuterium with high-energy particles accelerated in a cyclotron.
Unfortunately, the amount of energy released in the reaction was considerably
less than the energy required to accelerate the particles. Brief fusion
reactions have been demonstrated in the detonation of thermonuclear weapons,
but these reactions are useless for power generation because they cannot be
controlled. If a way can be found to produce a controlled fusion reaction,
this technology offers great promise as a source of electric power. The
combination of abundant fuel sources and no harmful byproducts makes fusion
power a safe alternative to the dangerous side effects produced by nuclear
fission.
Genetic Engineering
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Genetic Engineering involves the manipulation of deoxyribonucleic acid (DNA).
DNA contains the genetic "code" which determines the inherited traits of
living organisms. By removing a section of an organism's DNA and replacing it
with that of another organism, the characteristics of the organism can be
altered. Since its inception, genetic engineering has produced a number of
important benefits, such as isolating the gene for interferon, a rare
substance that may be of great value in the treatment of viral diseases and
cancer. Genetic manipulation may someday also provide a cure for birth defects
and inherited diseases. Unfortunately, there are also potential dangers
involved in this technology. Genetically engineered diseases, more
communicable and virulent than any occurring in nature, could potentially be
created in the laboratory by accident or maliciously. Such viruses could be
used as a dreadful biological weapon. Domestic and international regulations
regarding genetic experimentation exist to prevent such a situation from
occurring.
Guerilla Warfare
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In extreme situations, usually spawned by an oppressive or militaristic system of government, small groups of citizens have been known to form armed factions. In many cases, these splinter groups lack the numbers, finances, and armament to start a full-scale revolution. Instead, they adopt a practice of undermining governmental authority through covert military operations. These operations usually take the form of hit-and-run raids, where rebel soldiers launch a surprise attack on an enemy target, then disappear into hiding, only to strike again at some other time and place. Such tactics, known as guerrilla warfare, seldom have an impact when judging individual actions. However, over many years, guerrilla factions can become a serious threat to governmental authority if the rebels cannot be caught and suppressed. Tactics of this sort were used to great effect by the partisan forces in Nazi-occupied Europe during World War II.
Gunpowder
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Gunpowder is a chemical mixture of saltpeter, sulfur, and charcoal. When ignited, it burns rapidly and explodes if contained to any degree. Gunpowder is believed to have been developed by the Chinese, who used it in fireworks as early as the 9th century, but it did not reach Europe until the 14th century. Europeans immediately saw the potential of this substance, and manufactured it for use in weapons as early as 1334. The discovery of gunpowder led to the invention of firearms, such as the musket, which led to the replacement of archers in most armies of the world by the late 1500s. Gunpowder marked one of the major technological turning points in military history, significantly changing the way wars were fought.
Horseback Riding
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The horse was first domesticated for transportation and warfare by tribesmen on the Asian steppes. These tribesmen used their superior mobility and speed to overwhelm the proto-civilizations just rising in southeast Europe and the Middle East. In approximately 2000 BC, domestic horses were introduced into Babylonia. Within the next several centuries, horses had spread throughout much of Europe and northern Africa. It was not long before nearly every civilization had put horses to work as field animals and as a means of transportation. Horses also went on to play an important role in the military conflicts of nearly every civilization in the world, both as mounts for horsemen and cavalry, and as draft animals for pulling war chariots and heavy weapons into battle.
Industrialization
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Industrialization involves the use of machines to dramatically increase productivity. Production of goods became concentrated in factories, where the combination of specialization of labor and automation reduced labor costs and, ultimately, the cost of the final manufactured product to the consumers. Industrialization revolutionized living standards, both positively and negatively. The rapid growth of production industries and the reduced cost of production has led to the prosperity of some of the richest families in history. Industrialization has also led to the creation of a blue collar working class. In newly industrialized nations, these workers, skilled only in their chosen trade, were often underpaid and forced to endure abominable working conditions.
Invention
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The contrivance of a previously unknown device, method, or process which can, in turn, be used to accomplish an objective in a ways thought to be impossible, is known as invention. Essentially, inventiveness is the ability to take one or more newly discovered concepts and find a way to put them to practical use. The earliest inventions of mankind date back to ancient stone and metal tools used for hunting, digging, and other everyday tasks. After writing allowed the ideas of various civilizations to be exchanged and studied, mankind's inventions became increasingly more useful and innovative. Most inventions are geared toward improving or simplifying human existence in some way. Often, inventions themselves make it possible to make new discoveries, which then go on to inspire better and more innovative inventions.
Iron Working
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Some examples of iron ornamentation date back to 4000 BC, but the use of iron for tools, weapons, and other practical purposes did not become common until much later. Prior to this time, bronze was the most widely used metal for such purposes. Although the term "Iron Age" denotes a period of time starting around 1000 BC, iron replaced bronze as the metal of choice at different times in different places. Iron is more common than both copper and tin, the component metals of bronze, but iron is seldom found in a free state it is most commonly found mixed with other minerals and elements. In order to be used, the iron must be separated from the ore. Once this technique was developed, and forges hot enough to melt the iron were developed, iron working became commonplace. Worked iron was harder, less brittle, and could hold a much sharper edge than bronze. Iron has remained an important metal throughout history, and is one of the major components in the production of steel.
Labor Union
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Labor unions arose in the 18th and 19th century in response to the poor working conditions brought on by an intense competition for jobs, and the increasing dependence of the working class on their employers created by the move toward industrialization. Early labor unions, formed by skilled laborers in specific fields, met with opposition from both employers and the government. In the 19th century, laws were passed legalizing trade unions, and by the 20th century unions were formed in semi- or unskilled fields such as mining, transportation, and dock working. Binding their interests together and bargaining collectively, trade unions forced factory and business owners to provide better working conditions and economic status for their workers.
Laser
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Laser is an acronym for "Light Amplification by Stimulated Emission of Radiation". Lasers produce an amplified, coherent beam of light by using photons to energize or excite the electrons in the beam. The principles for the underlying theory of the stimulated emission of light was first proposed by Einstein in 1917. The first helium-neon gas laser was built in 1961. Years of research and development have led to a wide variety of laser applications in many different fields. Lasers can be used for everything from the precision cutting of almost any material and performing micro-surgery to reading digital data and music information off of a compact disc. The military currently uses lasers for weapons targeting systems, and it has been proposed that laser technology could be used to defend against an enemy missile attack.
Leadership
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Through the Middle Ages, military forces were only assembled as needed, and continued to serve until the current conflict had ended. Though certain leaders had proven to be adept and occasionally brilliant in their methods, the short periods for which they served made their fame short-lived. As regular armies became more prevalent, military leaders had the opportunity to distinguish themselves through the formulation of brilliant military tactics. The tactics of leaders such as these would be studied by successive generations, and modified to fit new situations up to and including the present day.
Literacy
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Writing was a powerful new tool for the advancement of knowledge, but, like all tools, it was only useful if employed. Literacy, the ability to read and understand a written language, was originally a skill limited to priests and scribes. Because of this, knowledge was still spread to the masses orally. Eventually, improving systems of education brought literacy to private citizens. Civilizations in which a high percentage of the population was literate had faster technological and economic growth than those where literacy was less common. In the modern world, while industrialized nations such as the U.S. enjoy widespread literacy, undeveloped nations still have illiteracy rates approaching 80 percent of their overall population. Illiteracy severely stunts the development of a country, even more so now than in the ancient world.
Machine Tools
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One of the most important steps in the move toward industrialization was the ability to precisely shape or "machine" solid metal into a desired form. Through mechanical, chemical, and other means, machine tools mold and shape raw materials into precision parts for complex machinery. The first machine tool, a horizontal boring device, was produced in the late 1700's. The development of measuring devices accurate to within a millionth of an inch allowed for the mass production of items with interchangeable parts. The technology of the 20th century has produced computer-controlled machine tools that can be adapted to a wide variety of applications. The speed and accuracy of these machines allows for the economical mass production of extremely complex products.
Magnetism
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The phenomenon of magnetism was known to the ancient Greeks, Romans, and Chinese. They observed that lodestone, an iron-bearing ore, attracted other iron. They also noted that pieces of iron that came into contact with lodestone gained magnetic properties as well. The electromagnetic force of attraction and repulsion between various substances is due to the motion of positively and negatively charged electrons. Every magnet has a positive and a negative side, called poles. Poles with a like charge repel one another, and poles with opposite charges attract one another. The study of magnetic phenomena soon showed that a free-floating magnet aligns itself with the Earth's magnetic field, one pole of the magnet pointing north, the other south. This was an important discovery, and led to the invention of the compass in the early 13th century. The use of the compass revolutionized sea travel by reducing the reliance on landmarks and stars for navigation.
Map Making
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Maps provide a diagrammatic representation of an area, showing terrain features, cities, and other landmarks. The earliest maps were etched clay tablets charting Babylonian lands for the purposes of taxation. Around the same time, the Chinese produced regional maps drawn on silk cloth. In between 600 and 200 BC, the Greeks produced several maps of the known world, including the first map showing a primitive system of latitude and longitude. These early maps were primarily used by traders and merchants. Seamen, who often set their courses based only on the tales brought back by previous voyagers, benefited most from the science of map making.
Masonry
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The early dwellings of most tribal cultures were built of materials that were readily available and easy to work with, such as bricks of clay and mud. As tribes gave up their nomadic ways and settled the first cities, they soon found that they had a need for more permanent and durable structures. The skill of masonry was developed to fill this need. The earliest stone structures consisted of little more than rocks which were stacked atop one another to form crude walls. Artisans soon began to square off the rocks, forming them into regular shapes and stacking them. These early examples of masonry used no mortar the weight of the stacked stones provided overall strength and stability. Without the use of mortar and knowledge of architectural techniques, masonry was used primarily for simple structures such as fortifications. However, some examples of early masonry are quite spectacular, including the Great Pyramids in Egypt, which are still standing after thousands of years.
Mass Production
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The idea of mass production began to take shape along with the factory system. The automation of production greatly increased productivity with a corresponding decrease in price for manufactured goods. In 1913, automobile manufacturer Henry Ford introduced the idea of assembly lines in his automobile plants. Products being built were conveyed from one work station to another along the line. At each station, a worker expertly repeated a discreet segment of the assembly process. The product then moved to the next station, and so on until the finished product rolled off the end of the line. This innovative combination of specialization of labor and the use of automation revolutionized production of complex goods. Word of Ford's assembly line technique spread quickly, and this production method soon came to be used in most of the industrialized nations of the world.
Mathematics
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Rudimentary arithmetic was purely quantitative, used to keep track of quantities and measurements in trade. Building on this fundamental base, ancient civilizations began to formulate more complex mathematical concepts. As early as 1800 BC, the Egyptians had developed a system for working with fractional numbers and simple algebraic problems. They also formulated geometric formulae for finding area and volume, and came up with a constant for determining the area of a circle that was very close to the value of pi. By about the 5th century BC, the mathematicians of Greece had greatly contributed to both geometry and algebra. Around the same time, advanced mathematics was applied to other sciences and fields of study such as astronomy and mechanics. One of the earliest applications of mathematical principles was in the construction of complex weaponry such as the catapult.
Medicine
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Primitive man attributed the onset of serious disease as the influence of the gods, or possession by evil spirits. Over time, however, it was found that such "possessions" could be treated through the use of elixirs made from plant extracts. Methods were also developed to clean and treat wounds, and set fractured bones. The ancient Greeks established the first schools to teach medical sciences circa 500 BC. The texts produced by the students of these schools, most notably Hippocrates, who is considered the father of medicine, based his theories of the human body on observation and reasoning rather than supernatural intervention. Continued study of diseases over the years, combined with the dissection and study of the human body in the 13th century, pointed out flaws in early Greek theories, and led to more accurate medical texts based on detailed analysis rather than conjecture. By the 18th century, the same methods of analysis and observation used by scientists in other fields were applied to the study of medicine. This paved the way for the increasingly effective methods of treatment and surgery that have prevailed over the last 200 years.
Metallurgy
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Metallurgy is the study of the properties of metals and the methods used to separate metal deposits from metal-bearing ores. Through the course of history, artisans have switched the materials from which they constructed weapons and tools to harder, more durable metals as they were discovered. However, metallurgy as a science wasn't studied in earnest until the powers of Europe began to compete against one another in an attempt to design better and more effective weapons starting around the 14th century. Constant improvements in metallurgy led to the discovery of new metals and alloys that were stronger, lighter, and cheaper. As a result of this race for military dominance, Europeans produced some of the most advanced weaponry in the world during this time period.
Miniaturization
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Early radios and other electronic devices relied on vacuum tube technology. Because the tubes took up a great deal of space, the devices that utilized them tended to be very bulky and cumbersome. In the late 1940's, the development of the transistor provided a compact alternative to vacuum tubes. Transistors were capable of achieving the same level of power amplification achieved by tubes while taking up much less space, and using only a fraction of the power. Starting in the 1960's, the integrated circuit provided still another level of miniaturization. An integrated circuit the size of a transistor could perform the function of 20 transistors. Today, the microprocessor, a modern refinement of the original integrated circuits, can incorporate the functions of several complete printed circuit boards into a single, low-power consumption chip less than two inches square, allowing for the construction of hand-held computers with more computing power than the huge mainframes used in the 70's and 80's.
Mobile Warfare
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The idea of using heavy weapons on the battlefield dates back to the 15th century when heavy cannons were mounted on wheels and towed into battle by horses. This first use of mobile artillery, devastatingly effective in its time, pales in comparison to the tactics used in 20th century armored warfare. Tanks were first used during World War I. A successful assault utilizing 400 tanks in November 1917, resulting in the capture of 8000 enemy troops and 100 guns near Cambrai, paved the way for a significant shift in battlefield tactics. During World War II, armored vehicles were used extensively throughout Europe and Africa by both Allied and Axis powers. The might and mobility of an armored assault was more than a match for countries who lacked proper defenses against such an attack. Armored warfare still plays an important role in battlefield tactics. This was proven in the Persian Gulf war, where the M1 Abrams tank proved to be a vital component of the ground assault force in Kuwait.
The Monarchy
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Rule by monarchy developed as a logical extension of the absolute rule of tribal chieftains. Many of the earliest monarchs, such as those in ancient Egypt, claimed that they ruled by divine right. In the spread of European monarchy during the Middle Ages, however, rulership was generally conveyed upon a leader who could most effectively raise and command an army. Monarchies are dynastic, with rule of the country passing to the eldest son when the king dies or retires. Monarchs had absolute rule over their subjects, severely limiting the personal and economic freedom of all citizens except for nobility and the rich upper-class. Although monarchies ruled most of Europe for centuries, the unhappiness of lower-class citizens eventually grew intolerable, causing several major revolutions. By the mid-18th century, the power of the European monarchs had been severely limited, paving the way for participatory systems of government.
Monotheism
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Monotheism is the belief that there is only one God. Perhaps the oldest monotheistic religion is Judaism. The original Israelites were polytheistic in a sense, since they did not deny the existence of other gods in addition to their own. However, after being exiled to Babylonia in 586 BC, the Judeans turned to a truly monotheistic religion, where the God of Israel was seen as the universal God ruling the destiny of all nations. The scriptures of Judaism became part of the teachings of the two most widespread monotheistic religions, Christianity and Islam. More developed than earlier polytheistic beliefs, monotheistic religions tend to encompass and structure the entire lifestyles of the people who practice them.
Mysticism
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People of the ancient world were fascinated and awed by the forces of nature surrounding them. Earthquakes, storms and other phenomena were generally regarded as signs from heaven. Individuals and groups arose to formulate explanations for these events, and pass the knowledge along to the tribe. The priests and priestesses of mysticism, often called oracles, claimed union with the divine through meditation and trance-like contemplation. Primitive mysticism offered mankind the first, tenuous links with the powers that shaped their world, and represented the first move toward the organized polytheistic and monotheistic religions to come.
Navigation
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In the early days of seafaring, sailors operated solely through a process known as "piloting", in which the position and course of the ship was determined by referring to geographical landmarks. The need to stay in view of the shore severely limited the extent of sea voyages. Through experience, sailors learned to apply the science of astronomy to their profession, noting the positions and movement of particular stars. They realized that even when the shore was out of sight, they could steer by certain reliable stars. This crude, yet practical application of astronomy allowed the adventurous to sail into the unknown with a reasonable chance of finding their way. As a result, ship building technology quickly improved, producing larger, more stable ships designed for longer voyages.
Nuclear Fission
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According to Einstein's theory of relativity, even the smallest bit of matter is equivalent to a tremendous amount of energy. For instance, two pounds of matter, if converted completely into energy, would produce energy equivalent to the explosive force of 22 megatons of high explosives. In 1939, based on German experiments that successfully split the uranium atom, physicists were able to explain the process of nuclear fission. When a large, unstable atomic nucleus splits (fissions) the result is two or more smaller, more stable nuclei accompanied by the release of tremendous amounts of energy and lingering, deadly radioactivity. The first application of this powerful technology was in warfare. A top-secret research effort in the U.S. known as the Manhattan Project studied the fission process, and eventually produced the first atomic bombs, which were dropped on the Japanese cities of Hiroshima and Nagasaki in 1945. These relatively small bombs, the only atomic weapons ever used in a war, each produced an explosion equivalent to more than 20,000 tons of TNT. The nuclear weapons of today are capable of producing explosions thousands of times more powerful.
Nuclear Power
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In addition to its potential for destruction, the energy released in nuclear
fission was seen as a potential source of controlled power generation. By
1944, large-scale nuclear reactors were in operation for the production of
plutonium, although the energy produced by these reactors was not used.
Following World War II, increased efforts were turned toward the extensive use
of nuclear power to produce electricity. Nuclear power plants use the radiant
energy of a controlled nuclear reaction to heat water, converting it to steam
to spin turbines that generate electricity. The major drawback to nuclear
fission is the lack of a safe means of disposal for the waste produced by the
reaction, which retains its lethal radioactivity for hundreds of years.
Another hazard is the possibility of a malfunction in the reactor that could
lead to a meltdown of the core. Despite massive safety precautions, human
error and equipment failures can lead to devastating accidents such as the
explosion at Chernobyl in 1986, in which at least 30 people were killed and
thousands lost their homes and face possible long-term illness after exposure
to near-lethal doses of radiation. Because of growing public concern, the
development of new nuclear power plants has slowed as scientists search for
viable solutions to these problems.
Philosophy
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The term philosophy comes from a Greek term meaning "love of wisdom." In ancient Greece, literacy and an interest in the natural world were common in a burgeoning upper class. In their leisure time, these people contemplated principles of thinking and being, logic and mathematics, and the natures of reality and existence. In ancient times, the study of philosophy was indistinguishable from the study of science, and many of the theories formulated by the early philosophers became the basis for studies in the fields of astronomy, medicine, chemistry, and physics. The teachings and writings of the ancient philosophers of Greece and the Orient also, in part, laid the groundwork for many of the world's oldest organized religions.
Physics
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Physics is the study of the many forms of matter and energy and of the way they interact with themselves and each other. A number of ancient races made observations about certain aspects of physics, such as planetary motion, but were unable to develop theories as to the reasons for these motions. Some of the earliest applications of physics were by the Greek mathematician Archemedes, who applied physics to create such devices as levers and screws. It was not until the 17th century that experimental methods and scientific measuring devices led to a true understanding of many fundamental physical laws. Early scientists such as Johannes Kepler and Sir Isaac Newton began to disprove the theories of the ancient Greek philosophers and scientifically prove their theories concerning the laws of physics. Discoveries in physics rarely have direct application, however they do provide a basic understanding of the laws governing the universe, thus forming the basis for practical advances in technology.
Plastics
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One of the spin-offs of researching more efficient ways to refine crude oil was the invention of plastics, organic polymer materials that retain their strength when molded into almost any shape. Starting in the 1920s, a flurry of research into the nature and fabrication of plastics resulted in widespread developments in the field, including the formulation of Plexiglas and nylon in the late 1930s. The boom in plastics research and development continued into and after World War II. Plastics were quickly adopted as cheap, sturdy substitutes for more traditional materials such as glass, rubber, and silk. It seemed that plastics were one of the most practical achievements of the Industrial Age. Despite their usefulness, plastics have proven to be an environmental hazard, since most plastics are not biodegradable,and they are therefore very difficult to dispose of. The significant pollution problem posed by plastics has been partially alleviated through the widespread implementation of recycling programs.
Polytheism
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Polytheism is the belief that the world and the environment is ruled or controlled by a number of different gods or divinities. Many ancient religions were polytheistic, notably those of the Egyptians, the Greeks, the Norse, and the Romans. Often, polytheistic religions have different gods for each force of nature and earthly phenomenon for instance: a sun god, a moon god, a god of thunder, a god of the forests, and so forth. The reason for such diversity in divine beings probably stems from ancient civilizations attempting to find explanations for natural events they could not understand. Although some isolated examples still exist today, most polytheistic religions have either died out or evolved into monotheism.
Pottery
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The invention of pottery was essential to the development of agricultural societies. To get the most out of seasonal crops and domesticated animals, a tribe needed sturdy, waterproof containers in which to store and protect surplus food. The discoveries of the properties of clay, the invention of the kiln, and the potter's wheel made it possible to build such containers. The earliest examples of Western pottery date back to as early as 6500 BC. Most of the examples from this period were strictly utilitarian. Although use continued to be primarily practical, decorative pottery soon became a ritualistic and aesthetic art form in cultures all over the world. Some of the most impressive examples of artistic pottery come from the pre-Columbian cultures of South America, and from the Ming dynasty in 14th century China.
Radio
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Prior to Gugliemo Marconi's invention of the radio in 1896, long-distance communication was carried out either by mail or over miles of cable via telegraph. Marconi's first demonstration of the radio telegraph transmitted a message just over one mile without the use of wires. Continued improvements increased transmission range to over 200 miles by early 1901, and by the end of the year a single letter ("A") had been transmitted across the Atlantic Ocean. By 1905, many ships were equipped with radio telegraphs for ship-to-ship and ship-to-land communications, and by 1915 the invention of the three-element vacuum tube, or triode, made it possible to regularly transmit voice messages over the airwaves. Throughout the years, radio has been refined not only for communication, but for detection and ranging (Radar) and astronomy.
Railroad
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The predecessors to modern railroads were wagonways, which were constructed in England starting in the 16th century. Wagonways were roads of parallel planks upon which coal wagons were pulled by horses at a greater speed than would have been possible on dirt roads. Wagonways were gradually improved by adding cross-ties and iron strips to reinforce the track. Eventually, the planks became metal rails, and evolved into the type of rails used on today's railroads by the start of the 19th century. Soon after the steam locomotive was introduced in 1829, it replaced horse-drawn wagons, giving birth to the railroad. Originally developed in Britain and the eastern United States as a method of hauling heavy mining ores and freight, railroads outshone canals in their ability to operate across any ground and in nearly any weather. When railroads started carrying passengers as well as goods, the potential for safe, fast, inexpensive transport became clear. Railroads led to a dramatic increase in the amount of cargo, passengers, news, and troops that could be moved quickly over great distances.
Recycling
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Increasing world population has led to an inevitable increase in the amount of garbage produced by society. Conventional disposal methods, such as burial in a landfill, have proven inadequate to handle the growing waste problem. One solution to this problem is the reuse of discarded materials through recycling. Although scrap metals and other materials have been reused in manufacturing processes for some time, true recycling is a broad-based, household-by-household effort. The increasing pollution generated by industry and consumerism, added to the depletion of natural resources, make the re-use of materials less a concern of efficiency and more as one of necessity for the survival of the human species. Not only does the recycling of waste materials prevent the unwanted build-up of garbage, it saves energy and slows the depletion of natural resources such as trees and petroleum products.
Refining
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When the demand for oil-based fuels for lighting and other purposes began to soar in the 19th century, scientists began searching for a way to make use of crude oil. This research led to techniques in which crude oil was broken down, or refined, into a number of different fuels, including kerosene and gasoline. As consumer demand continued to increase, commercial refineries were set up to purify crude oil. The new petroleum products produced as a result of the development and perfection of the refining process led to the use of oil-based fuels in many consumer and industrial applications. These include the use of gasoline to power automobiles, and the use of oil for heating and for the generation of electrical power.
Refrigeration
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Prior to World War I, ice was the most widely used means of refrigeration for perishable items. After the war, electrical refrigerators became commonly available. The availability of these systems allowed for more constant and efficient cooling, in turn allowing perishable meats, dairy products, and other items to be stored, or even frozen, for long periods of time. As a result, food producers could increase their output, since excess food could be stored for later sale or consumption. The concept of the wholesale selling of bulk foods (known as the supermarket) was, in part, made possible by improved refrigeration. The same method used in food refrigeration was also developed for use in air conditioners.
The Republic
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The republic is a system of government in which the citizens appoint, by popular vote, a head of state and officials to represent the views of the general public. The concept of the republic first appeared in ancient Rome, where local provinces sent elected representatives to the Senate, which governed all Roman lands. Both the head of state and the local representatives in a republic are elected no one is granted a position by birth or divine right. Republican governments are similar in some ways to democracies, in that they offer a great deal of personal, financial, and political freedom to their citizens. The main difference between the two systems is that a true democracy allows the participation of every voting citizen in any and all political matters, whereas in a republic, the views and opinions of the people are represented by a body of elected officials. Although an effective system, personal agendas of political representatives might act to decrease the effectiveness in representing the views of the people. Due to human nature, corruption is fairly common in a republican government.
Robotics
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The creation of machines to assist in, and increase the efficiency of, the manufacturing process gave birth to the factory system of production and started the Industrial Revolution. The invention of digital computers in the late 1940's, and their refinement over the next several decades, took factory automation one step further. Computer-controlled machines, called robots, were designed to perform repetitive or dangerous tasks more quickly than humans. Experimental robots capable of simple manipulation of objects were in operation by the late 1960's. The first robots used on an assembly line were commissioned by General Motors in the 1970's. Constant improvements in the computer field have allowed the production of incredibly versatile robots, capable of performing a wide variety of tasks under virtually any environmental condition. Robots today are widely used in manufacturing, scientific research, and space exploration.
Rocketry
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Rockets are projectiles that are propelled by the expulsion of gases generated in a combustion chamber. The first solid-fuel rockets, invented by the Chinese in the 13th century, used a mixture similar to gunpowder for fuel. Although rockets were used in warfare to set fire to buildings and the sails of ships for nearly 500 years, it wasn't until the early 19th century that the first crude explosive rockets were used in battle. Research and design efforts by scientists such as Robert Goddard in the 20th century refined rocket design to produce faster, better controlled rockets. During World War II, this new technology was used to create the German V-2 "buzz bomb", the first true guided missile. Scientific developments since World War II have been applied to adapt the rocket for use in even more powerful and accurate weapons with incredible range. The rocket is also used in peaceful application such as the launch of satellites and the exploration of space.
Sanitation
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The increased waste produced by growing populations over time eventually led to potential health hazards. It then became necessary to come up with systems to dispose of garbage and human waste in a sanitary manner. Plumbing systems designed to remove waste water from dwellings and public buildings became commonplace, as did sewage plants which treated the wastewater before it was dumped into local waterways. Landfills were established, and garbage was collected for sanitary disposal in dumps and landfills a safe distance from the general population. These measures led to a healthier environment, and allowed for further population growth.
Seafaring
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As empires grew and trade expanded to new areas, travel by sea became increasingly important to the civilizations of the world. Experienced sailors passed down their lore and techniques to new generations who sailed to increasingly distant lands. Originally, these long voyages were trade-oriented. But the ability to travel great distances led to a new breed of adventurers whose goal was primarily one of exploration. The Vikings were some of the earliest and most successful explorers in history. Their knowledge of the sea and experience with long ocean voyages allowed explorers such as Leif Ericson to successfully cross the Atlantic and land in the Americas more than 500 years before Columbus. The pioneering spirit of these early ocean travelers formed the basis for the seafaring traditions of generations to come.
Space Flight
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Utilizing the now well-developed science of rocketry, the modern exploration of space began in October, 1957 when the Soviet Union launched Sputnik 1. This tiny satellite orbited the earth for 57 days, providing information on radiation and other phenomena in the upper atmosphere. In less than a year, the United States had also launched a satellite, Explorer 1. This started the "space race", years of competition between the U.S. and the U.S.S.R. to achieve new frontiers in space exploration. Space flight advanced rapidly from the simple sub-orbital flights of the 1950's, to manned missions to Earth's moon in the late 1960's. The rapid growth of space technology led to many practical applications, such as weather and surveillance satellites, and vastly improved worldwide communications. Today, although hindered by severe government budget cuts, the exploration of space continues. Plans in the near future call for continued orbital exploration via the space shuttle program, and the eventual construction of the multi-national, manned space station "Freedom" in the early 21st century.
Stealth
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It has long been recognized that in warfare, the best advantage available is surprise. If one can approach an enemy undetected, the attack has a better chance of being successful. The widespread use of radar starting in World War II greatly decreased the possibility of surprise for an airborne assault. Planes could be detected from miles away, giving the enemy a chance to prepare for the attack. Over the years, the military has employed many different approaches to solve this problem. The most recent development is "Stealth" technology. Stealth planes are painted with radar-absorbing paint, and designed in such a way as to minimize the number of angular surfaces from which an enemy can bounce a radar signal. The engines are also hooded to reduce the plane's heat signature. The result is an aircraft capable of approaching an enemy target, launching an attack, and returning to base with little chance of detection. The F-117A Stealth Fighter was used with great effectiveness by US forces in the Persian Gulf War in 1991.
Steam Engine
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The steam engine is a device that uses steam to generate power. Water, heated by burning fuel (usually coal or wood), turns to steam. The steam is contained in a chamber where it builds up pressure, causing a piston to move. The piston drives a turbine, the rotation of which produces power which can be use for such purposes as producing motion or generating electricity. The early principles of this device were understood as early as the late 17th century, but it wasn't until 1769 that Scottish engineer James Watt patented a practical design for what was to become the basis for the modern steam engine. The invention of the steam engine led to a number of landmark developments, including the steam locomotive and the earliest examples of automobiles. Steam engines remained the chief means of motive power in the transportation industry until the invention of the more powerful and compact internal combustion engine. Steam turbines are still in use today in a number of applications including the generation of electrical power.
Steel
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The iron alloys produced up until about the 14th century were made by heating a mixture of iron ore and charcoal in a forge, then pounding the molten metal to drive out the impurities or "slag". Occasionally, the iron mixture would absorb more carbon, creating steel rather than wrought iron. Because steel proved to be less brittle and more resistant to corrosion than iron, techniques were developed to produce steel. This was done by blowing a coal derivative called coke through molten iron. Most modern steel making utilizes the "blast furnace", developed by Henry Bessemer in 1855, to accomplish this task on a large-scale basis. The strength and other qualities of steel make it the material of choice for warships, planes, and many other vehicles.
Superconductor
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Any material through which an electrical current can pass with relatively little resistance is known as a conductor. When an electric current passes through most conductors, part of that current is lost due to resistance, which varies depending on the conducting material and the ambient temperature. Some conductors, when cooled to temperatures near absolute zero, lose all resistance to current. These are known as superconductors. Because no energy is lost to resistance, superconductors can lead to a wide variety of practical uses. These include super-fast computers, powerful electromagnetic fields strong enough to contain fusion reactions, and the completely efficient generation and transmission of electrical power. Although the extremely low temperatures necessary to produce superconductivity have limited its uses thus far, recent developments hint that some unusual materials may be superconductive even at room temperatures. The isolation and large-scale production of these materials could lead to a new revolution in the field of electronics.
Tactics
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The science of the deployment of military forces to accomplish a short-range goal or objective is known as tactics. In unique or difficult situations, the maneuvers and methods of attack must be chosen wisely to give ones troops the maximum possible advantage over the enemy by taking advantage of the enemy's weaknesses. The successful tactics of military commanders are studied by their successors for possible modification and use under current conditions. Although tactics that work well in certain situations may not always be successful when used again, proven military tactics have worked well in many different battle situations throughout history. The vast amount of advanced equipment and resources available in modern warfare make the proper tactical coordination of a campaign vital, but difficult to achieve with total success.
Theology
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Theology is the study of God and religious truth. Theologians take a more or less scientific approach to questions of religion, deeply studying the underlying meaning of scriptures and religious teachings rather than "taking them on faith". Theological seminaries teach courses of study in theology to prepare people as priests and clergymen. Many of the earliest colleges of the western world were originally established for this purpose. Theological study helped to remove some of the superstitions that had surrounded religion for so long, and brought religious study into a more enlightened age.
Theory of Gravity
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In the 17th century, Sir Isaac Newton developed the law of universal gravitation. This law recognized that every mass in the universe exerts an attraction on every other mass. Newton postulated that gravity was a universal force that affected all matter. Newton's theory served to explain the forces of attraction between the Earth and nearby objects, as well as the forces that affect the motion of planets and other astronomical bodies. In the early 20th century, Albert Einstein's special theory of relativity led to a major reinterpretation and clarification of Newton's theory of gravity. Scientists now believe that gravity affects energy as well as matter, and that gravity is actually a fundamental warping of the fabric of space-time. Some theorize that the force of this warping is transmitted by as-yet-unobserved particles called gravitons.
Trade
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One of the oldest and most widespread social institutions is the exchange of goods, or trade. Most ancient trade consisted of barter, where two traders would exchange goods with one another. The widespread practice of trade allowed civilizations to exchange raw materials and goods which they had in abundance or could easily produce, for items that were rare or nonexistent in their geographic region. The introduction of regulated currency that could be exchanged for items resulted in easier, more convenient trade. Merchants soon roamed the world, connecting different lands with webs of economic interdependence. In addition to goods and profits, traders also brought back tales and technology from these foreign lands. Well-traveled traders like Marco Polo were among the most learned sources on the cultures and traditions of foreign lands.
University
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Institutes of higher learning, such as the Academy of Plato in Athens which taught advanced philosophical principles, existed in the ancient world. It was not until the 12th century, however, that the model for the modern university system was born. In the Middle Ages, some royal governments and ecclesiastical organizations founded exclusive schools dedicated to training young men in specific professions. At that time, each university specialized in a single topic like law, theology, music, or medicine. Through the centuries, universities diversified to include a number of different fields of study. Modern universities consists of several faculties, or colleges, each of which has a specific curriculum. In addition to their roles as learning institutions, universities have, since their inception, acted as centers for scientific research and advancement.
Warrior Code
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The samurai of feudal Japan lived by a doctrine known as "Bushido", or "the way of the warrior". This code of behavior stressed such virtues as loyalty, courage, and politeness. The honor of the warrior could only be maintained if the rules of the code were followed. A similar code of behavior known as chivalry was later developed under the feudal system in medieval Europe. Although the strict adherence to both Bushido and chivalry were abandoned along with the feudal system in the 1800's, certain principals of discipline and behavior inherent in these systems can still be found in the military today.
Wheel
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The invention of the wheel represented a major turning point in human civilization. The first wheels, disks carved from solid wood, may have been built as early as 3500 BC. The earliest use of this device was the potter's wheel, used to spin and shape clay pottery. It was not long before the true potential of the wheel was discovered, and wheeled carts soon replaced the sledge as a means of transportation. Rapid developments, such as wheels consisting of a ring with radial spokes, made the wheel even more practical by reducing its weight. By using the wheel, mankind gained the ability to work more efficiently and travel more quickly. Besides its use in transportation, the wheel went on to become the basic principle behind almost every mechanical device.
Writing
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The development of writing is considered one of the most important advances of civilization. The earliest forms of writing were simple symbols and marks, used to keep accounts and inventories. Some cultures developed pictographic symbols to tell stories and record events. Eventually, complete systems of writing were developed, capable of conveying any thought that could be expressed orally. At this point, scribes replaced the oral historian as the chief keepers of records. Writing allowed the presentation of information in a form that could be reliably transmitted from person to person and made it possible for ideas, history, and knowledge to be stored permanently and passed between cultures more reliably than through oral recitation.
Future Technology
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Since the dawn of mankind, human needs and desires have combined to produce ideas and inventions that make life easier and more productive. New technological breakthroughs have become an almost daily occurrence in the modern era, and new ideas will continue to drive human knowledge to higher and higher levels well into the future.
Settlers
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When cities grew to a size where the resources were insufficient to adequately insure a decent standard of living for the populace, adventurous groups of citizens set out on their own in search of a place to build a new city. Once a suitable site was found, the settlers would build their new homes, and develop the land surrounding the city. Eventually, the whole process repeated, and the new city would send out settlers of its own. This process allowed civilizations to grow throughout history, from the empires of the ancient world to the discovery and settlement of the New World.
Engineers
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As technology progressed through the centuries, people began to specialize in a single skill or field of knowledge. The early pioneers who acted in the multiple roles of farmers, builders, and just about any other occupation required by their situation, were replaced by engineers specifically trained in a single discipline. Specialized training provided engineers the time and the skill necessary to accomplish feats of construction and environmental manipulation never before experienced in history.
Warriors
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The earliest military forces were simply the citizens of the city, armed with whatever implements they could use as weapons. Although a militia made up of warriors was inexpensive, they were no match for organized armies. Warriors were usually used as a stopgap measure while waiting for superior units to be trained, or to defend a city that has been temporarily cut off from military support. In a crisis situation, an assembly of warriors is a better choice than no defense at all.
Phalanx
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The phalanx was a military formation developed in Greece, and perfected in Macedonia. It consisted of a large group of soldiers in ranks and files, usually from 8 to 32 men deep, armed with spears, swords, and large shields. The first five ranks of men pointed their weapons forward, forming a bristling barrier of spearpoints, while the others kept their spears upright to deflect incoming missiles. An enemy had difficulty approaching this formation. The attacking army was faced with a densely packed body of warriors, who were often advancing on the run. This usually caused the attackers to give ground rather than risk being impaled. Unfortunately, the phalanx lacked maneuverability, and became less prevalent when enemy forces became more professional and learned to outflank the formation.
Archers
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The bow and arrow, invented in prehistoric times, greatly improved the hunting skills of early man, allowing him to kill his targets from a distance. The bow was eventually adapted for use in battle, and was first used by Egyptian, Persian, and Assyrian armies as early as 5000 BC. The range provided by the bow allowed small forces of archers to rout armies of superior number who were armed with hand-to-hand weapons. Archers were often used to soften enemy resistance prior to sending in mounted and skirmishing forces. Refinements in design and construction allowed the bow to remain an effective weapon until it was finally replaced by firearms in the 1500's.
Legion
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The Roman Legions, created during the early wars of the Republic and tested during the three Punic Wars against Carthage, were the fighting force that conquered and held the Roman Empire for five centuries. Each legion was composed of 6000 men, divided into 60 smaller groups known as centuries. Nearly unstoppable on the attack, the legion was relatively weak on defense. The legion's demise as a military unit was accelerated by the destruction of Emperor Valens' army by gothic knights in the 4th Century.
Pikemen
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The growing deployment of knights on the battlefield demanded that foot soldiers develop new means of fighting that would lessen their vulnerability against mounted opponents. One of the best ways to do this was to lengthen the reach of the infantrymen by arming them with long, sturdy spears known as pikes. Massed infantry armed with pikes, in conjunction with archers, managed to even the battlefield odds. Armies equipped in this manner managed to hold their own until the invention of gunpowder made knights a thing of the past.
Musketeer
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One of the most important developments in the history of warfare was the invention of firearms. Originally developed in the 14th century, firearms evolved quickly, and by the late 17th century flintlock muskets had become commonplace in battle. Musketeers, who were relatively inexpensive to equip and train, proved a deadly foe for the knights who had dominated the battlefield for so many years. Armies were often comprised of a combination of musketeers, cannon, and knights, each complementing the strengths and weaknesses of one another. Large forces of musketeers within a fortress or behind city walls proved an exceedingly difficult obstacle to an attacking army. Muskets were the primary firearm in use until they were replaced by repeating rifles in the mid-19th century.
Fanatics
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Certain circumstances, such as strong religious beliefs or a totalitarian system of government, can "inspire" citizens or factions to nationalism that approaches maniacal fervor. Fanatical groups can often succeed in seemingly hopeless situations, fighting and defeating superior enemy forces. Often, fanatics pursue military and terrorist activity for years, even decades, before they can be caught or stopped. Their strength for both attack and defense comes from their willingness to fight for the ideals they believe in, and, if necessary, sacrifice their lives in the name of their cause.
Partisans
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Partisans are militant groups who pledge their support to a leader or a system of government. Partisans differ from fanatics in their methods. Whereas fanatics are usually radicals prone to use terrorist tactics, partisans are usually trained soldiers who practice the more organized tactics of guerrilla warfare. Partisan groups have existed at various times throughout history. Partisans were particularly active in the Nazi occupied countries of Europe during World War II, where their acts of sabotage against their conquerors often kept German troops busy quelling partisan uprisings while they should have been fighting on the front lines. Because of their unflagging dedication to their cause, partisans make formidable opponents.
Alpine Troops
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In the colder regions of the world, where winter months tend to leave the ground snow covered, skiing often became one of the most reliable means of transportation. In the alpine countries of Europe, it became commonplace to train special groups of soldiers to take advantage of the snow covered, mountainous terrain by traveling on skis. This proved to be a huge advantage, especially if the enemy forces were not likewise equipped. In November 1939, for example during the Russo-Finnish War, the Finns managed to cut off the supply and communications lines of the vastly superior Russian army through the use of their extremely mobile ski troops, and the Finns continued to hold an advantage throughout the winter months. Alpine troops continue to be trained and utilized in military forces of the present day.
Riflemen
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Two developments in the 19th century made early firearms such as the musket obsolete. The first was the use of a spiral groove, or "rifling", inside the barrel of a gun. Second, was the development of the repeating rifle, which could fire multiple shots before it required reloading. The rifle was a better weapon than its ancestors, with much more accuracy over a greater range than the musket. Riflemen were first employed in large numbers during the American Civil War. The rifle gave a strong defensive advantage, since riflemen could fire several times while the attackers advanced. This was normally enough to hold any position. Riflemen held the advantage on the battlefield until the appearance of armored attack vehicles.
Marines
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The Marines are a branch of the military service that operates separately, but is under the ultimate control of the secretary of the navy. The Marine Corps is a combined branch of the military their training prepares them to carry out integrated land, sea, and air operations. The first marines were commissioned during the American Revolution, only to be inactivated after the war. The Marine Corps was then permanently reestablished by Congress in July, 1798. Legendary for their toughness, rigid codes of behavior, and adaptability, they have played an important role in almost every major war and conflict of the 19th and 20th centuries.
Paratrooper
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Although the idea of the parachute was suggested in the 16th century drawings of Leonardo da Vinci, the first parachute was not invented until the late 1700's. For years, parachutes were standard emergency equipment for balloonists. Claire Chennault, an American pioneer of aviation pursuit tactics during World War I, was the first to suggest using parachutes to drop troops behind enemy lines. This idea was widely used. Paratroopers were flown behind enemy lines in transport planes and dropped from low altitude, allowing them to attack the enemy from behind. Today, paratroopers are usually highly-trained special forces personnel, trained to covertly infiltrate enemy territory.
Mechanized Infantry
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The introduction of armored tanks meant that armies could quickly break through enemy defensive positions and move aggressively forward on the battlefield. Such a quick advance, however, left the ground won in the advance largely undefended. Mechanized infantry, which was first used during World War II, was designed to be able to move in quickly and defend the area behind the tanks. Infantry were mounted in armored vehicles, such as half-tracks and Armored Personnel Carriers (APCs), to carry them quickly and safely along with the rapidly advancing armored divisions.
Horsemen
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The necessity for speed and mobility in times of war was recognized even in ancient times. The infantrymen of some ancient armies would ride horses to get from one engagement to another, dismounting to fight when they reached the battlefield. Because of their speed, horsemen could also be used as scouts to pinpoint enemy positions. In the second century BC, the Chinese invention of the stirrup allowed this concept of mobility to go one step further. Stirrups provided the stability and leverage necessary to allow soldiers to fight from horseback, leading to the earliest examples of cavalry units. Continuous developments in arms and armor eventually led to knights, dragoons, and finally the advanced cavalry of the 18th and 19th century.
Chariot
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The chariot was the first true fighting vehicle. It was used by ancient armies to transport archers and other troops to the battlefield, where they would disembark and fight. The chariot was turned into a fearsome offensive weapon by the Assyrians, whose archers and spearmen fought from inside the chariot itself. Few enemies were able to withstand an onslaught of Assyrian chariots. This devastating form of attack was soon adopted by many of the Assyrian's enemies, who used the chariot against them with good effect.
Elephant
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The elephant is the largest living land mammal, reaching a size of 10 to 13 feet in height depending on the species. Descended from the ancient mammoths and mastodons, elephants can be trained to serve humans in many fields of endeavor. One such use of elephants in ancient times was as beasts of war. Elephants were used in battle against Alexander the Great in 326 BC, and they were used both as pack animals and in battle by Hannibal of Carthage in his famous alpine crossing in 218 BC. Although generally impractical as mounts due to their slow speed, the mere mental impact of seeing such massive beasts included in the advancing enemy ranks could provide an attacker with the element of surprise.
Crusaders
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Between 1095 and 1270, European Christians waged a series of wars known as the Crusades. These holy wars, sanctioned by the Pope, were fought to free the Christian Holy Lands from Muslim control. The crusaders themselves were a mixed lot, with many different backgrounds and reasons for fighting. However, most of them joined the ranks out of religious fervor, and a feeling that their personal salvation was guaranteed when fighting for such a holy cause. Despite the fact that the crusaders fought with all the strength of their religious conviction, the Crusades accomplished very little in a military sense however, the European economy and desire for exploration was greatly increased.
Knights
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Knights were heavily armored, mounted men-at-arms in medieval Europe. Like the samurai of ancient Japan, knights followed a strict code that covered their behavior both in battle and in their personal pursuits. Fighting astride powerful horses, armored knights had a distinct advantage over enemies on foot and remained the dominant force on the battlefield when battles were primarily fought hand-to-hand. Occasionally, brilliant tactics allowed knights to be outmaneuvered, but it wasn't until the development of gunpowder that knights were rendered obsolete.
Dragoons
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Dragoons were mounted soldiers armed with short muskets who fought, both on horseback and on foot, during the time of the American Revolution. The name comes from the French word for "dragon", and refers to the "fire breathing weapons" used by these troops. British general John Burgoyne utilized a force of Hessian dragoons to attack an American supply base in the Battle of Bennington in 1777. Despite their large numbers, the dragoon mercenaries were severely routed by several detachments from the New Hampshire militia.
Cavalry
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Cavalry are mounted soldiers trained to fight on horseback. Because of their speed, cavalry units were often used for reconnaissance missions and hit-and-run raids on enemy installations and troops. Although warriors fighting from horseback with a variety of weapons dates back to ancient Egypt, horse-mounted cavalry as we generally think of it today actually began in the late 1700's. Under Napoleon, the cavalry became an elite force, frequently deployed simultaneously with foot soldiers, to mask the movements of the main battle force. Cavalry were used extensively in the American Civil War, and in other conflicts throughout the mid to late 19th century. When the repeating rifle replaced earlier single-shot firearms, horse-mounted troops became easy targets for infantrymen. The South African War, from 1899 to 1902, was the last major conflict where cavalry played a major role. Today, the roles once performed by horse-mounted cavalry have been assumed by troops utilizing armored assault vehicles and aircraft.
Armor
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The rise in the use of semi-automatic and automatic firearms in the late 19th and early 20th century led to the demise of horse-mounted cavalry. Attackers lost a significant advantage in both scouting and deployment as a result of the cavalry's vulnerability. It was only with the development of tanks, armored mobile attack vehicles equipped with high caliber guns, that a weapon was found which could once more be used to punch a hole through enemy field forces. First appearing in World War I, armored attack vehicles moved quickly and struck with power, while still possessing an effective defensive strength. Tanks are a powerful weapon against any ground unit.
Catapult
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The catapult was one of the earliest forms of artillery. It was a large mechanical arm that propelled heavy stones and other missiles from a great distance, battering down walls and inflicting damage on buildings and defenders. Though cumbersome and nearly useless on the battlefield, the catapult was an effective weapon for attacking cities and fortified enemies.
Cannon
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Closely following the invention of gunpowder, the development of the cannon caused a revolution in siege warfare. Invented by a German monk in the 14th century, early cannons used gunpowder charges to fire rocks or metal balls. The cannon forced a redesign of most fortifications because the straight, high walls surrounding most cities could be easily destroyed by direct fire. This was the fate of the walls of Constantinople, which had held against countless sieges for over a thousand years. The cannon quickly assumed an important role on the battlefield.
Artillery
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Artillery is a general term covering several varieties of large caliber weapons including mortars and field guns. Mortars fire an explosive projectile in a high arc, and are particularly effective against small, concealed targets. Field guns, long-range weapons that fire their projectiles in a flat arc, are used primarily for their ability to penetrate hard targets. Powerful enough to batter opposing forces even behind the strongest fortifications, artillery is also able to move quickly from one firing position to another. This is an important capability when fighting a moving battle or when avoiding enemy fire.
Howitzer
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The howitzer is a specialized piece of artillery. As originally designed, the howitzer was a cross between the short-ranged mortar and the long-ranged field gun. When fired in a high arc, the howitzer shell was able to achieve the mortar's effectiveness against small, concealed targets. When fired in a flat trajectory, the shell had more range than the mortar and the penetration power of the field gun. Howitzers were easier to transport than other types of heavy artillery due to their smaller size, and could be mounted on wheels and towed by a truck. Modern light howitzers fire a variety of specialized ammunition, and their accuracy now makes them more efficient and lethal than older heavy howitzers and field guns.
Fighter
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The earliest military aircraft were used primarily in a reconnaissance role. In 1915, during World War I, aircraft designer Anthony Fokker developed a gear system that allowed a plane-mounted machine gun to fire through the propeller, giving birth to the first fighter aircraft. The fighter's mission was to shoot down enemy reconnaissance and fighter planes. Later, as the use of bombers became more widespread, fighters were called upon to act as interceptors against enemy bombing runs and escorts for friendly bombers. The best way to ensure the safe passage of friendly bombers to their selected targets is the destruction of enemy fighters.
Bomber
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The bombing of strategic targets from the air dates back to the beginning of World War I, when the Germans used zeppelins to bomb Paris and London. Because zeppelins proved to be extremely vulnerable, they were withdrawn from war in favor of airplanes. By the end of World War I, planes were being designed specifically as bombers. The bomber's job is to carry bombs into enemy territory, normally beyond the range of artillery, and destroy targets of military and economic value. Bombers were often designed for specific missions, such as attacking ships, bombing vehicles and railroads, daylight precision bombing, and carpet bombing.
Helicopter
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The concept that was to become the modern helicopter was first explored by artist/engineer Leonardo da Vinci. He made sketches of a rotor-driven aircraft in the early 16th century. It was not until 1939, however, that the first practical helicopter design was developed. Helicopters have a distinct advantage over fixed-wing aircraft in that they can take off and land vertically. This makes it possible for helicopters to operate in many places that would be too small to accommodate a runway. Today, helicopters are used in civilian roles as rescue vehicles and by law enforcement agencies. All branches of the military utilize many different types of helicopters, from giant cargo and troop carriers to fast and maneuverable gunships used as air support for ground troop operations.
Stealth Fighter
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Starting in the Second World War, radar technology came into widespread use both for detection and targeting of aircraft. Because of this, aeronautical engineers began searching for ways to make aircraft less "visible" to electronic tracking and weapon systems. The earliest stealth technologies consisted of coating aircraft with materials that would absorb rather than deflect a radar signal. In the late 1970s, designs incorporating this technology, as well as a unique fuselage shape designed to deflect radar away from its source, were prototyped. The first true stealth fighter, the Lockheed F-117A, flew for the first time on June 18, 1981. This fighter, incorporating the latest anti-radar and anti-thermal innovations, is capable of entering enemy territory, delivering its payload, and returning to base with little chance of detection. These unique, black aircraft served well in the Persian Gulf War in 1991, and have served as the basis for further development of stealth aircraft technology.
Stealth Bomber
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Concurrent with the development of a stealth fighter, aeronautical engineers began to apply stealth technology to a full-scale bomber. The B-1B bomber, which went into service in 1986 as a replacement for the B-52, incorporated some of these innovations. The radar signature of the B-1B was reduced to a mere 1 percent that of the B-52 due to its low cross-section and its minimal use of radar-reflective, hard-edged surfaces. Soon after the B-1B entered service, the U.S. Air Force commissioned Northrop to develop a true stealth bomber as an eventual replacement. First revealed to the public in 1988, the B-2 stealth bomber uses a flying wing design similar in shape to the F-117A stealth fighter. The flying wing design reduces the profile of the B-2 by incorporating its engines into the body of the plane. The engine exhausts and intakes are shielded to prevent infrared tracking. The B-2 also makes use of curved surfaces and radar-absorbing materials to enhance its "invisibility", and make it far less detectable than the B-1B. As of the late 1980s, it was announced that 132 B-2's would be constructed, and would enter service sometime in the 1990s.
Trireme
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The trireme was the first ship designed for war. Introduced by the Greeks, triremes were powered by three banks of oars on each side, manned by well-trained oarsmen. These oarsmen were highly paid professionals or patriotic citizens, not slaves and prisoners as depicted in fiction. A huge, bronze "beak" mounted at the bow of the ship was used to ram and sink enemy ships. Because of its long, narrow hull, the trireme was very unstable in all but the calmest waters, and as a consequence its crew rarely ventured out of sight of land for long periods of time, lest the ship be caught in a storm and sunk.
Caravel
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The caravel was a small sailing ship with three or four masts, a broad bow, and a high, narrow stern.. Though often used as a warship, the caravel could also carry just over 100 metric tons of cargo. Caravels were commonly used by the Spanish and the Portuguese for both commerce and exploration. Christopher Columbus' three ships, the "Nina", "Pinta", and "Santa Maria", were all caravels.
Galleon
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By the late 15th century, oar-powered vessels had all but disappeared from the world's oceans, to be replaced by sailing vessels of various types. The galleon was one such vessel. Galleons were three- or four-masted ships, built high in both the forecastle and the stern. Developed in the 15th and 16th century, these versatile ships were mainly used as cargo vessels, although they were sometimes outfitted as light warships as well. Ships of this type served European nations well into the 1700s.
Frigate
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The frigate was a fast and powerful sailing warship that evolved to fill several important naval roles, primarily to raid enemy shipping. These three masted ships were lighter and faster than the European great ship or man-of-war, and usually carried 36 or fewer guns. The frigate was powerful enough to overcome most of its prospective opponents and fast enough to escape those it could not outgun. Because of their speed and strength, frigates were often employed as escorts for merchant vessels during times of war. The frigate remained the most useful and dominant naval vessel until the development of the ironclad.
Ironclad
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Ironclads were the forerunners of future generations of armored naval vessels. Instead of the simple wooden hulls found on the other ships at the time, ironclads were covered with strong metal plating. This plating made them nearly impervious to large-caliber explosive shells that would easily penetrate and destroy wooden vessels. Ironclads made their first appearance during the American Civil War, and quickly gained dominance over other ships of that era. Perhaps the most famous naval battle of the Civil War was the battle between the Confederate ironclad "Merrimack", and the Union ironclad "Monitor", which lasted for several hours before the "Merrimack" was forced to withdraw.
Destroyer
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Destroyers are small escort ships that serve a variety of useful functions.
These light, fast vessels were used extensively in World War II to provide air
and sea cover for carrier groups. One of the primary functions of the
destroyer is to locate and destroy enemy submarines. Using their sonar
equipment to locate the subs, and their batteries of depth charges and
torpedoes to destroy them, the destroyer forces of World War II were the key
to the success of many crucial naval operations. Modern destroyers are still
used in much the same role, as escorts for larger vessels and as submarine
hunters. In addition to five-inch guns, the arsenal of today's destroyer
includes anti-submarine helicopters, anti-ship cruise missiles, and the Phalanx
system for defense against anti-ship missiles.
Cruiser
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The cruiser is the modern equivalent of the frigate. Although much more powerful than its sailing forebearer, it is designed for the same type of mission: to act as a sea raider and escort. Cruisers can conduct shore bombardments, though their firepower cannot match the destructive force of the battleship. The cruiser's defensive capabilities are also inferior to those of the battleship. These shortcomings are balanced by the cruiser's lower cost and higher speed. Cruisers serve an important role in scouting missions, convoy escorts, and the attack of transport vessels.
AEGIS Cruiser
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Cruisers have long served in the role of escort and defensive vessels, screening carrier task forces and amphibious assaults from enemy ships and aircraft. In recent years, the abilities of the cruiser have been upgraded significantly. In addition to their traditional five-inch guns, cruisers also carry batteries of Harpoon and Tomahawk missiles. The latest development in cruiser armament is the AEGIS surface-to-air missile system, which allows cruisers to target and fire their missiles more accurately and more effectively than ever before. The cruisers of today are highly capable of intercepting and destroying enemy submarines, surface ships, aircraft, and missiles.
Battleship
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The battleship was once the most powerful vessel on the seas. Heavily armored and difficult to destroy, its massive guns could accurately fire heavy projectiles at targets miles away. The battleship had two primary functions: clearing the seas of enemy ships and bombarding enemy coastal targets, usually in preparation for an invasion. The battleship's importance began to decline in World War II when the increasing use of fighters and bombers launched from aircraft carriers greatly extended the range of naval conflicts. Ship-to-ship combat became less frequent than long-range air attacks against enemy battle groups. The last of the U.S. Navy's battleships was decommissioned shortly after the Vietnam War, but the four battleships of the Iowa class were remodeled and recommissioned in the 1980's.
Submarine
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A submarine is a submersible warship, designed to attack enemy vessels while remaining hidden underwater. Although defensively weak, submarines are feared because of their ability to make a stealthy approach and attack without warning. Often, the presence of a submarine is not detected until the first of the sub's torpedoes strikes its target. Submarine warfare was first used extensively by the Germans during World War I. Developments after the war, such as sonar, made the submarine even more effective. During World War II, submarines were used extensively by all the world's naval powers. Today's submarines, in addition to their role as fast attack vessels, also carry nuclear weapons that can be fired from underwater positions just off the coast of an enemy country.
Carrier
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The aircraft carrier first came into widespread use during World War II. Carriers act as floating airfields, carrying fighters and bombers far from friendly territory to be launched against enemy targets. This allows an air strike against targets on both land and sea that would otherwise be far out of range. Carriers also have the capability to launch nuclear weapons. The range of the aircraft launched from carriers forever changed the methodology of naval battles. Opposing fleets could now engage in battle without either fleet ever entering the other's visual range, ending the dominance of the battleship as the strongest vessel on the sea.
Transport
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The troop transport ship, which in peacetime serves as a cargo or passenger vessel, is the principle means used by modern powers to move large quantities of military equipment and personnel over long distances. Because transports lack offensive weaponry, they require armed vessels as escorts during times of war. A properly escorted transport can move large military forces to a new area quickly to act as reinforcements or as an attacking force.
Cruise Missile
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One of the most effective weapons in modern military arsenals is the cruise
missile. Cruise missiles such as the AGM-86 and the Tomahawk can be launched
against a strategic target hundreds of miles away, traveling low to avoid
radar and other means of detection, and hitting its target with unnerving
accuracy. They can also be used against short-range, tactical targets such as
ships. In this role, it is often possible for a single, $1 million missile to
seriously damage or even destroy $80 million warships. These versatile weapons
can be launched from air, sea, or land with equal effectiveness.
Nuclear Missile
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The deployment of atomic bombs at Nagasaki and Hiroshima at the end of World War II changed the world's standards for measuring military power. Nuclear weapons can eradicate ground forces and armored divisions, and flatten cities with their awesome explosive power. In the years following World War II, arsenals of nuclear weapons were built up rapidly by opposing nations, each fearing the capabilities of the other. This massive arms build up has acted as a deterrent to full-scale war, since all the governments involved are aware of the consequences should such a war take place. The threat imposed by the huge nuclear arsenals of the world powers may one day be eradicated by the development of the Strategic Defense Initiative, or SDI, a system designed to destroy enemy missiles in flight before they can reach their targets.
Diplomat
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Diplomats serve their homeland in a variety of ways. Their primary function is to maintain contact with other civilizations, and report on any developments of interest. Diplomats are also capable of engaging in less reputable activities, including sabotage of enemy production the theft of civilization advances and the subversion of enemy troops and cities. Although they have no combat value, diplomats are nevertheless potent weapons if utilized properly.
Spy
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One of the most effective ways to compile information about an enemy (or potential enemy) is by infiltrating the enemy's ranks. This is the job of the spy. Spies can bring back all sorts of information concerning the size and strength of an enemy army. They can also find dissidents within the enemy's forces and influence them to defect. In times of crisis, spies can also be used to steal technology and to sabotage the enemy in various ways. Counterintelligence operatives can feed false information to enemy spies, protecting important domestic secrets and preventing attempts at subversion. Nearly every society has very strict laws concerning espionage, and the penalty for being caught is often death. However, the benefits that can be gained through espionage are generally felt to outweigh the risks.
Caravan.
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Trade has been a major source of income to civilizations throughout history. Journeying to distant lands, caravans exchanged their loads of goods for money or other items of value. In addition, the traders who accompanied the caravans often brought back new knowledge about the advances made by the civilizations with whom they did business. Marco Polo, for example, went with traders to China. He remained there for many years, and brought back much valuable information to the West.
Freight
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Freight units are the modern day equivalent of the trade caravans in the ancient world. Whereas in early history raw materials, trade goods, food, and manufactured items were transported by camel or wagon, modern shipments are transported by a variety of methods including trucks and railroads. The speed and convenience of modern transportation methods allows civilizations to set up supply routes and move large quantities of merchandise and trade goods farther and faster than ever.
Explorer
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Since the dawn of history, there has been a need for humans to investigate their surroundings and expand their knowledge of the world around them. Even the earliest civilizations sent people in search of wealth and resources in distant lands. With the advent of extensive sea travel, explorers such as Christopher Columbus and Amerigo Vespucci mapped and charted territories far from their homelands. These early explorers opened the New World to trade and colonization.
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