Chicago the City of Chicago, is the most populous city in Illinois, as well as the third most populous city in the United States. With an estimated population of 2,716,450, it is the most populous city in the Midwest. Chicago is the principal city of the Chicago metropolitan area referred to as Chicagoland, the county seat of Cook County, the second most populous county in the United States; the metropolitan area, at nearly 10 million people, is the third-largest in the United States, the fourth largest in North America and the third largest metropolitan area in the world by land area. Located on the shores of freshwater Lake Michigan, Chicago was incorporated as a city in 1837 near a portage between the Great Lakes and the Mississippi River watershed and grew in the mid-nineteenth century. After the Great Chicago Fire of 1871, which destroyed several square miles and left more than 100,000 homeless, the city made a concerted effort to rebuild; the construction boom accelerated population growth throughout the following decades, by 1900 Chicago was the fifth largest city in the world.
Chicago made noted contributions to urban planning and zoning standards, including new construction styles, the development of the City Beautiful Movement, the steel-framed skyscraper. Chicago is an international hub for finance, commerce, technology, telecommunications, transportation, it is the site of the creation of the first standardized futures contracts at the Chicago Board of Trade, which today is the largest and most diverse derivatives market gobally, generating 20% of all volume in commodities and financial futures. O'Hare International Airport is the one of the busiest airports in the world, the region has the largest number of U. S. highways and greatest amount of railroad freight. In 2012, Chicago was listed as an alpha global city by the Globalization and World Cities Research Network, it ranked seventh in the entire world in the 2017 Global Cities Index; the Chicago area has one of the highest gross domestic products in the world, generating $680 billion in 2017. In addition, the city has one of the world's most diversified and balanced economies, not being dependent on any one industry, with no single industry employing more than 14% of the workforce.
Chicago's 58 million domestic and international visitors in 2018, made it the second most visited city in the nation, behind New York City's approximate 65 million visitors. The city ranked first place in the 2018 Time Out City Life Index, a global quality of life survey of 15,000 people in 32 cities. Landmarks in the city include Millennium Park, Navy Pier, the Magnificent Mile, the Art Institute of Chicago, Museum Campus, the Willis Tower, Grant Park, the Museum of Science and Industry, Lincoln Park Zoo. Chicago's culture includes the visual arts, film, comedy and music jazz, soul, hip-hop and electronic dance music including house music. Of the area's many colleges and universities, the University of Chicago, Northwestern University, the University of Illinois at Chicago are classified as "highest research" doctoral universities. Chicago has professional sports teams in each of the major professional leagues, including two Major League Baseball teams; the name "Chicago" is derived from a French rendering of the indigenous Miami-Illinois word shikaakwa for a wild relative of the onion, known to botanists as Allium tricoccum and known more as ramps.
The first known reference to the site of the current city of Chicago as "Checagou" was by Robert de LaSalle around 1679 in a memoir. Henri Joutel, in his journal of 1688, noted that the eponymous wild "garlic" grew abundantly in the area. According to his diary of late September 1687:...when we arrived at the said place called "Chicagou" which, according to what we were able to learn of it, has taken this name because of the quantity of garlic which grows in the forests in this region. The city has had several nicknames throughout its history such as the Windy City, Chi-Town, Second City, the City of the Big Shoulders, which refers to the city's numerous skyscrapers and high-rises. In the mid-18th century, the area was inhabited by a Native American tribe known as the Potawatomi, who had taken the place of the Miami and Sauk and Fox peoples; the first known non-indigenous permanent settler in Chicago was Jean Baptiste Point du Sable. Du Sable arrived in the 1780s, he is known as the "Founder of Chicago".
In 1795, following the Northwest Indian War, an area, to be part of Chicago was turned over to the United States for a military post by native tribes in accordance with the Treaty of Greenville. In 1803, the United States Army built Fort Dearborn, destroyed in 1812 in the Battle of Fort Dearborn and rebuilt; the Ottawa and Potawatomi tribes had ceded additional land to the United States in the 1816 Treaty of St. Louis; the Potawatomi were forcibly removed from their land after the Treaty of Chicago in 1833. On August 12, 1833, the Town of Chicago was organized with a population of about 200. Within seven years it grew to more than 4,000 people. On June 15, 1835, the first public land sales began with Edmund Dick Taylor as U. S. Receiver of Public Monies; the City of Chicago was incorporated on Saturday, March 4, 1837, for several decades was the world's fastest-growing city. As the site of the Chicago Portage, the city became an important transportation hub between the eastern and western United States.
Chicago's first railway and Chicago Union Railroad, the Illi
Body of water
A body of water or waterbody is any significant accumulation of water on a planet's surface. The term most refers to oceans and lakes, but it includes smaller pools of water such as ponds, wetlands, or more puddles. A body of water contained. Most are occurring geographical features, but some are artificial. There are types. For example, most reservoirs are created by engineering dams, but some natural lakes are used as reservoirs. Most harbors are occurring bays, but some harbors have been created through construction. Bodies of water that are navigable are known as waterways; some bodies of water collect and move water, such as rivers and streams, others hold water, such as lakes and oceans. The term body of water can refer to a reservoir of water held by a plant, technically known as a phytotelma. Bodies of water are affected by gravity, what creates the tidal effects on Earth. Note that there are some geographical features involving water that are not bodies of water, for example waterfalls and rapids.
Arm of the sea – sea arm, used to describe a sea loch. Arroyo – a dry creek bed or gulch that temporarily fills with water after a heavy rain, or seasonally. See wadi. Artificial lake or artificial pond – see Reservoir. Barachois – a lagoon separated from the ocean by a sand bar. Bay – an area of water bordered by land on three sides, similar to, but smaller than a gulf. Bayou – a slow-moving stream or a marshy lake. Beck – a small stream. Bight – a large and only receding bay, or a bend in any geographical feature. Billabong – an oxbow lake in Australia. Boil – see Seep Brook – a small stream. Burn – a small stream. Canal – an artificial waterway connected to existing lakes, rivers, or oceans. Channel – the physical confine of a river, slough or ocean strait consisting of a bed and banks. See stream bed and strait. Cove – a coastal landform. Earth scientists use the term to describe a circular or round inlet with a narrow entrance, though colloquially the term is sometimes used to describe any sheltered bay.
Creek – a small stream. Creek – an inlet of the sea, narrower than a cove. Delta – the location where a river flows into an ocean, estuary, lake, or reservoir. Distributary or distributary channel – a stream that branches off and flows away from a main stream channel. Drainage basin – a region of land where water from rain or snowmelt drains downhill into another body of water, such as a river, lake, or reservoir. Draw – a dry creek bed or gulch that temporarily fills with water after a heavy rain, or seasonally. See wadi. Estuary – a semi-enclosed coastal body of water with one or more rivers or streams flowing into it, with a free connection to the open sea Firth – a regional term of Scotland used to denote various coastal waters, such as large sea bays, estuaries and straits. Fjord – a narrow inlet of the sea between cliffs or steep slopes. Glacier – a large collection of ice or a frozen river that moves down a mountain. Glacial pothole – a kettle Gulf – a part of a lake or ocean that extends so that it is surrounded by land on three sides, similar to, but larger than a bay.
Headland – an area of water bordered by land on three sides. Harbor – an artificial or occurring body of water where ships are stored or may shelter from the ocean's weather and currents. Impoundment – an artificially-created body of water, by damming a source. Used for flood control, as a drinking water supply, ornamentation, or other purpose or combination of purposes. Note that the process of creating an "impoundment" of water is itself called "impoundment." Inlet – a body of water seawater, which has characteristics of one or more of the following: bay, estuary, fjord, sea loch, or sound. Kettle – a shallow, sediment-filled body of water formed by retreating glaciers or draining floodwaters. Kill – used in areas of Dutch influence in New York, New Jersey and other areas of the former New Netherland colony of Dutch America to describe a strait, river, or arm of the sea. Lagoon – a body of comparatively shallow salt or brackish water separated from the deeper sea by a shallow or exposed sandbank, coral reef, or similar feature.
Lake – a body of water freshwater, of large size contained on a body of land. Lick — a small watercourse or an ephemeral stream Loch – a body of water such as a lake, sea inlet, fjord, estuary or bay. Mangrove swamp – Saline coastal habitat of mangrove trees and shrubs. Marsh – a wetland featuring grasses, reeds, typhas and other herbaceous plants in a context of shallow water. See Salt marsh. Mediterranean sea – a enclosed sea that has limited exchange of deep water with outer oceans and where the water circulation is dominated by salinity and temperature differences rather than winds Mere – a lake or body of water, broad in relation to its depth. Mill pond – a reservoir built to provide flowing water to a watermill Moat – a deep, broad trench, either dry or filled with water and protecting a structure, installation, or town. Ocean – a major body of salty water that, in totality, covers about 71% of the Earth's surface. Oxbow lake – a U-shaped lake formed when a wide meander from the mainstem of a riv
The Hualapai is a federally recognized Indian tribe in Arizona with over 2300 enrolled members. 1353 enrolled members reside on the Hualapai Indian reservation, which spans over three counties in Northern Arizona. The name, meaning "people of the tall pines", is derived from hwa:l, the Hualapai word for ponderosa pine and pai "people", their traditional territory is a 108-mile stretch along the pine-clad southern side of the Grand Canyon and the Colorado River with the tribal capital at Peach Springs. The Hualapai tribe is a sovereign nation and governed by an executive and judicial branch and a tribal council; the tribe provides a variety of social, cultural and economic services to its members. The Hualapai language is a Pai branch of the Yuman–Cochimí languages spoken by the related Havasupai, more distantly to Yavapai people, it is still spoken by most people over 30 on the Reservation as well as many young people. The Peach Springs School District runs a successful bilingual program for all local students, both Hualapai and non-Hualapai, in addition to immersion camps.
The Hualapai Indian Reservation, covering 1,142 square miles, was created by the Presidential Executive order of Chester A. Arthur on January 4, 1883. Major traditional ceremonies of the Hualapai include the "Maturity" ceremony and the "Mourning" ceremony. Nowadays the modern Sobriety Festival is celebrated in June; the souls of the dead are believed to go northwestward to a beautiful land where plentiful harvest grow. This land is believed to be seen only by Hualapai spirits. Traditional Hualapai dress consists of full suits of rabbit skin robes. Conical houses formed from cedar boughs using the single slope form called a Wikiup; the Hualapai Reservation was created by executive order in 1883 on lands that just four regional bands considered as part of their home range, like the Yi Kwat Pa'a or Ha'kasa Pa'a. The other Hualapai regional bands lived far away from the current reservation land; the Hualapai War was caused by an increase in traffic through the area on the Fort Mojave-Prescott Toll Road which elevated tensions and produced armed conflicts between the Hualapai and European Americans.
The war broke out in May 1865, when the Hualapai leader Anasa was killed by a man named Hundertinark in the area of Camp Willow Grove and in March 1866. In response, a man named Clower was killed by the Hualapai, who closed the route from Prescott, Arizona to the Colorado River ports due to the conflict; the most important and principal Hualapai leaders at that time were: Wauba Yuba, Hitchi Hitchi and Susquatama. It was not until William Hardy and the Hualapai leaders negotiated a peace agreement at Beale Springs that the raids and the fighting subsided. However, the agreement lasted only nine months when it was broken with the murder of Chief Wauba Yuba near present-day Kingman during a dispute with the Walker Party over the treaty. After the chief's murder, raids by the Hualapai began in full force on mining settlers; the cavalry from Fort Mojave responded, with the assistance of the Mohave, by attacking Hualapai rancherias and razing them. The pivotal engagement took place in January 1868, when Captain S.
B. M. Young joined in by Lt. Johnathan D. Stevenson, surprised the rancheria of Sherum with his more than one hundred warriors. Known as the Battle of Cherum Peak, it lasted all day. Stevenson fell in the first volley; the Hualapai lost twenty-one warriors, with many more wounded. The Battle broke the military resistance of the Hualapai; the Hualapai began to surrender, as whooping cough and dysentery weakened their ranks, on August 20, 1868. They were led by Chief Leve Leve of the Amat Whala Pa'a of the Yavapai Fighters subtribe; the warrior Sherum, known for his tenacity as a warrior surrendered, thus marking the end of the Hualapai Wars in 1870. It is estimated that one-third of the Hualapai people were killed during this war either by the conflict or disease. Ethnically, the Havasupai and the Hualapai are one people, although today, they are politically separate groups as the result of U. S. government policy. The Hualapai had three subtribes - the Middle Mountain People in the northwest, Plateau People in the east, Yavapai Fighter in the south.
The subtribes were divided into seven bands, which themselves were broken up into thirteen regional bands or local groups. The local groups were composed of several extended family groups, living in small villages: The Havasupai were one band of the Plateau People subtribe. Ko'audva Kopaya included seven bands in the plateau and canyon country east of the Grand Wash Cliffs, the eastern Hualapai Valley, this area include the current Hualapai Reservation, bands listed from west to east: Mata'va-kapai Ha Dooba Pa'a / Haduva Ba:' Tanyika Ha' Pa'a / Danyka Ba:' ("Grass Springs band", were able to st
Glass brick known as glass block, is an architectural element made from glass. The appearance of glass blocks can vary in color, size and form. Glass bricks provide visual obscuration while admitting light; the modern glass block was developed from pre-existing prism lighting principles in the early 1900s to provide natural light in manufacturing plants. Today glass blocks are used in walls and sidewalk lights; the texture and color of glass blocks can vary. Patterns can be pressed into either the inner void or the outside surface of the glass when it is cooling in order to provide differing effects. Glazes or inserts may be added in order to create a desired private or decorative effect. Glass blocks in Europe are manufactured in accordance with the European Standard EN1052-2; the International Standard is ISO TC 160/SG1. The Standards allow for variation in sizes and production irregularity. Blocks fall within three classifications. There are newer Glass Blocks injected with Argon gas and having a layer of low-emissivity glass between the halves, which increases the insulative value to 1.5 W/m²·K, between triple glazed windows and specialty double glazed windows with advanced frame and coatings.
Glass blocks can provide light and serve as a decorative addition to an architectural structure, but hollow glass blocks are non load-bearing unless stated otherwise. Hollow glass wall blocks are manufactured as two separate halves and, whilst the glass is still molten, the two pieces are pressed together and annealed; the resulting glass blocks will have a partial vacuum at the hollow center. Due to the hollow center, wall glass blocks do not have the load-bearing capacity of masonry bricks and therefore are utilized in curtain walls. Glass block walls are constrained based on the framing. If a masonry or steel frame exists, the maximum area of the wall can be 144 square feet, whereas the maximum area without a frame is 100 square feet; the William Lescaze House and Office, built in 1934, was the first house in New York City to use glass blocks as walls. Glass blocks used in flooring are manufactured as a single solid piece, or as a hollow glass block with thicker side walls than the standard wall blocks.
These blocks are cast into a reinforced concrete gridwork or set into a metal frame, allowing multiple units to be combined to span over openings in basements and roofs to create skylights. Glass wall blocks should not be used in flooring applications because the way in which they are manufactured does not allow them to support a load. Glass wall blocks are fixed together to form complete walls by several methods – the most common method of construction is to bed the blocks together in a Portland cement-based mortar with reinforcing rods of steel placed within the mortar as recommended by the project architect or block manufacturer. Other methods of construction include several proprietary systems whereby the mortar is replaced by timber or PVC extrusions. Specialist glass blocks are produced for various applications including: Bullet and vandal resistant blocks are solid glass or have thick side walls similar to pavement blocks. Fire resistance of varying degrees can be achieved by several methods.
Standard production hollow wall block will offer little fire resistance. Some manufacturers of glass blocks have developed a method of bonding two glass blocks together with adhesive, producing blocks of up to 160 mm thick with enhanced fire resistance, it is important that the block manufacturer's recommendations are followed with regards to the installation of fire resisting glass block walls, as without special construction techniques, the wall will not achieve the desired fire resistance. A recent innovation in the manufacture of glass blocks is the inclusion of argon gas within the hollow centre of glass wall blocks; this advancement in production technique has resulted in a glass block, able to offer improved thermal insulation properties. Some hollow glass wall blocks are available in coloured variants; these coloured variants fall into two categories. The other method by which coloured glass blocks are achieved is to inject a coloured material, dye or transparent paint into the hollow centre of the blocks to form a permanent coating.
This method of producing coloured blocks enables vibrant colours to be achieved which are not possible with coloured glass. The downside of this production method is that the coloured coating may not be UV stable and can fade in bright sunshine over time and may therefore not be suitable for all locations. Modern glass bricks were preceded by Falconnier Hollow Glass Bricks in the late nineteenth century. Falconnier Bricks were blown glass bricks available in multiple colors and were formed in molds while the glass was molten. An early 20th century summary of glass brick use: The Falconnier bricks could be used for walls or roofs and were joined together with wire and cement; the suggested use for Falconnier glass bricks was in greenhouse construction due to the non-conductivity of the glass for temperature contro
Pavement lights, vault lights, floor lights, or sidewalk prisms are flat-topped walk-on skylights set into pavement or floors to let sunlight into the space below. They use anidolic lighting prisms to throw the light sideways under the building, they declined in popularity with the advent of cheap electric lighting. Some cities are systematically removing historic sidewalk lights. Pavement lights have been used in a few new architectural designs. Sidewalk prisms are a method of daylighting basements, are able to serve as a sole source of illumination during the day. At night, lighting in the basements beneath produces a glowing sidewalk. Vault lights may be used to make subterranean space useful, they are more common in city centers, high-rent areas where space is valuable. Landlords took an interest in improving not only the floor area ratio, but the amount of space, lit, on the grounds that this was profitable. Occupiers valued daylight not only as a way of saving on artificial lighting costs, but as a way to let premises remain cooler in summer, a way to save on ventilation costs.
Pavement lights and related products were marketed as a way of saving on artificial lighting costs and making space more usable and pleasant. Modern studies of similar daylighting technology provide evidence for those claims. Vault lights are used in floors under glass roofs, for example in Budapest's historic Párizsi udvar and New York's mostly-demolished old Pennsylvania Station. Vault lights could be set into the basement floor, underneath other vault lights, creating a double-deck arrangement, which would light the subbasement. Manhole covers and coalhole covers with lighting elements were made; some steps have vault lights set into the vertical stair risers. Older cities and smaller centers around the world have had pavement lights. Most such lights are a century old, although lights are being installed in some new construction. A basement that extends below a sidewalk or pavement is called an areaway, a sidewalk vault, or a hollow sidewalk. In some cities, these areaways were created by the raising of the street level to combat floods, in some cases they form an underground tunnel network.
To light these spaces, sidewalks incorporated gratings, which were a trip hazard and let water and street dirt as well as light into the basement. Replacing the open gratings with glass was an obvious improvement. Sidewalk prisms developed from deck prisms; the earliest pavement light used a single large round glass lens set in an iron frame. The large lens was directly exposed to traffic, if the lens broke, a large hole was left in the pavement, unsafe for pedestrians. Thaddeus Hyatt corrected these faults with his "Hyatt light" of 1854. Many small lenses were set in a wrought-iron frame, the frame included raised nubs around each lens to improve traction in wet weather and to protect them from damage and wear. If all the lenses were broken out, the panel would still be safe to walk on. In the 1930s, London authorities ruled that glass sections could not be larger than 100 mm by 100 mm. Modern glass floors are made of laminated and toughened glass pavers, which can be larger, they have an upper protective layer that can be replaced if it becomes cracked.
The top surface of the pavers may be chosen and treated to improve traction. Wrought iron, cast iron, stainless steel frames have all been used. Reinforced concrete slabs began to replace iron frames in the 1890s in New York. Benefits claimed included a less slippery surface when wet. Concrete panels may be cast in-situ. Late concrete panels were made with metal-framed "armored prisms", which were intended to prevent breakage and make replacing individual prisms easier; the glass is not caulked into the frame. Rather than chiselling out the old glass, the glass can be popped out of the frame. Translucent concrete has been proposed as a floor material; this would make it a vault light with small lighting elements. It innately redirects the light from the angle of incidence to an angle ~parallel to the optical fibers; the transparent elements may be referred to as lenses, or as jewels. The glass in many old pavement lights is now either straw-colored; this is a side-effect of the manufacturing process.
Pure silica glass is transparent, but older glass manufacture used silica from sand, which contains iron and other impurities. Iron produces a greenish tint in the finished glass. To remove this effect, a "decolorizer" such as manganese dioxide was added during the manufacture of the glass; when exposed to ultraviolet light, the manganese "solarizes", turning purple, why many existing sidewalk prisms are now purple. WWI increased demand for manganese in the US and cut off the supply of high-grade ore from Germany, so selenium dioxide was used as a decolorizer instead. Selenium solarizes, but to a straw color. Replacement glass, tinted purple deliberately, in order to match the current colour, has been used in some historic restoration projects. In 1871 London, Hayward Brothers patented th
Surrealism is a cultural movement that began in the early 1920s, is best known for its visual artworks and writings. Artists painted unnerving, illogical scenes with photographic precision, created strange creatures from everyday objects, developed painting techniques that allowed the unconscious to express itself, its aim was to "resolve the contradictory conditions of dream and reality into an absolute reality, a super-reality". Works of surrealism feature the element of unexpected juxtapositions and non sequitur. Leader André Breton was explicit in his assertion that Surrealism was, above all, a revolutionary movement. Surrealism developed out of the Dada activities during World War I and the most important center of the movement was Paris. From the 1920s onward, the movement spread around the globe affecting the visual arts, literature and music of many countries and languages, as well as political thought and practice and social theory; the word'surrealism' was coined in March 1917 by Guillaume Apollinaire three years before Surrealism emerged as an art movement in Paris.
He wrote in a letter to Paul Dermée: "All things considered, I think in fact it is better to adopt surrealism than supernaturalism, which I first used". Apollinaire used the term in his program notes for Serge Diaghilev’s Ballets Russes, which premiered 18 May 1917. Parade was performed with music by Erik Satie. Cocteau described the ballet as "realistic". Apollinaire went further, describing Parade as "surrealistic": This new alliance—I say new, because until now scenery and costumes were linked only by factitious bonds—has given rise, in Parade, to a kind of surrealism, which I consider to be the point of departure for a whole series of manifestations of the New Spirit, making itself felt today and that will appeal to our best minds. We may expect it to bring about profound changes in our arts and manners through universal joyfulness, for it is only natural, after all, that they keep pace with scientific and industrial progress; the term was taken up again by Apollinaire, in the preface to his play Les Mamelles de Tirésias, written in 1903 and first performed in 1917.
World War I scattered the writers and artists, based in Paris, in the interim many became involved with Dada, believing that excessive rational thought and bourgeois values had brought the conflict of the war upon the world. The Dadaists protested with anti-art gatherings, performances and art works. After the war, when they returned to Paris, the Dada activities continued. During the war, André Breton, who had trained in medicine and psychiatry, served in a neurological hospital where he used Sigmund Freud's psychoanalytic methods with soldiers suffering from shell-shock. Meeting the young writer Jacques Vaché, Breton felt that Vaché was the spiritual son of writer and pataphysics founder Alfred Jarry, he admired the young writer's anti-social disdain for established artistic tradition. Breton wrote, "In literature, I was successively taken with Rimbaud, with Jarry, with Apollinaire, with Nouveau, with Lautréamont, but it is Jacques Vaché to whom I owe the most."Back in Paris, Breton joined in Dada activities and started the literary journal Littérature along with Louis Aragon and Philippe Soupault.
They began experimenting with automatic writing—spontaneously writing without censoring their thoughts—and published the writings, as well as accounts of dreams, in the magazine. Breton and Soupault wrote The Magnetic Fields. Continuing to write, they came to believe that automatism was a better tactic for societal change than the Dada form of attack on prevailing values; the group attracted additional members and grew to include writers and artists from various media such as Paul Éluard, Benjamin Péret, René Crevel, Robert Desnos, Jacques Baron, Max Morise, Pierre Naville, Roger Vitrac, Gala Éluard, Max Ernst, Salvador Dalí, Luis Buñuel, Man Ray, Hans Arp, Georges Malkine, Michel Leiris, Georges Limbour, Antonin Artaud, Raymond Queneau, André Masson, Joan Miró, Marcel Duchamp, Jacques Prévert, Yves Tanguy. As they developed their philosophy, they believed that Surrealism would advocate the idea that ordinary and depictive expressions are vital and important, but that the sense of their arrangement must be open to the full range of imagination according to the Hegelian Dialectic.
They looked to the Marxist dialectic and the work of such theorists as Walter Benjamin and Herbert Marcuse. Freud's work with free association, dream analysis, the unconscious was of utmost importance to the Surrealists in developing methods to liberate imagination, they embraced idiosyncrasy, while rejecting the idea of an underlying madness. As Salvador Dalí proclaimed, "There is only one difference between a madman and me. I am not mad."Beside the use of dream analysis, they emphasized that "one could combine inside the same frame, elements not found together to produce illogical and startling effects." Breton included the idea of the startling juxtapositions in his 1924 manifesto, taking it in turn from a 1918 essay by poet Pierre Reverdy, which said: "a juxtaposition of two more or less distant realities. The more the relationship between the two juxtaposed realities is distant and true, the stronger the image will be−the greater its emotional power and poetic reality."The group aimed to revolutionize human experience, in its
A planetarium is a theatre built for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation. A dominant feature of most planetaria is the large dome-shaped projection screen onto which scenes of stars and other celestial objects can be made to appear and move realistically to simulate the complex'motions of the heavens'; the celestial scenes can be created using a wide variety of technologies, for example precision-engineered'star balls' that combine optical and electro-mechanical technology, slide projector and fulldome projector systems, lasers. Whatever technologies are used, the objective is to link them together to simulate an accurate relative motion of the sky. Typical systems can be set to simulate the sky at any point in time, past or present, to depict the night sky as it would appear from any point of latitude on Earth. Planetariums range in size from the 37 meter dome in St. Petersburg, Russia to three-meter inflatable portable domes where attendees sit on the floor.
The largest planetarium in the Western Hemisphere is the Jennifer Chalsty Planetarium at Liberty Science Center in New Jersey. The Birla Planetarium in Kolkata, India is the largest by seating capacity. Thereafter, the China Science and Technology Museum Planetarium in Beijing, China has the largest seating capacity. In North America, the Hayden Planetarium at the American Museum of Natural History in New York City has the greatest number of seats; the term planetarium is sometimes used generically to describe other devices which illustrate the solar system, such as a computer simulation or an orrery. Planetarium software refers to a software application that renders a three-dimensional image of the sky onto a two-dimensional computer screen; the term planetarian is used to describe a member of the professional staff of a planetarium. The ancient Greek polymath Archimedes is attributed with creating a primitive planetarium device that could predict the movements of the Sun and the Moon and the planets.
The discovery of the Antikythera mechanism proved that such devices existed during antiquity, though after Archimedes' lifetime. Campanus of Novara described a planetary equatorium in his Theorica Planetarum, included instructions on how to build one; the Globe of Gottorf built around 1650 had constellations painted on the inside. These devices would today be referred to as orreries. In fact, many planetaria today have what are called projection orreries, which project onto the dome a Sun with planets going around it in something close to their correct relative periods; the small size of typical 18th century orreries limited their impact, towards the end of that century a number of educators attempted some larger scale simulations of the heavens. The efforts of Adam Walker and his sons are noteworthy in their attempts to fuse theatrical illusions with educational aspirations. Walker's Eidouranion was the heart of theatrical presentations. Walker's son describes this "Elaborate Machine" as "twenty feet high, twenty-seven in diameter: it stands vertically before the spectators, its globes are so large, that they are distinctly seen in the most distant parts of the Theatre.
Every Planet and Satellite seems suspended without any support. Other lecturers promoted their own devices: R E Lloyd advertised his Dioastrodoxon, or Grand Transparent Orrery, by 1825 William Kitchener was offering his Ouranologia, 42 feet in diameter; these devices most sacrificed astronomical accuracy for crowd-pleasing spectacle and sensational and awe-provoking imagery. The oldest, still working planetarium can be found in the Dutch town Franeker, it was built by Eise Eisinga in the living room of his house. It took Eisinga seven years to build his planetarium, completed in 1781. In 1905 Oskar von Miller of the Deutsches Museum in Munich commissioned updated versions of a geared orrery and planetarium from M Sendtner, worked with Franz Meyer, chief engineer at the Carl Zeiss optical works in Jena, on the largest mechanical planetarium constructed, capable of displaying both heliocentric and geocentric motion; this was displayed at the Deutsches Museum in 1924, construction work having been interrupted by the war.
The planets travelled along overhead rails, powered by electric motors: the orbit of Saturn was 11.25 m in diameter. 180 stars were projected onto the wall by electric bulbs. While this was being constructed, von Miller was working at the Zeiss factory with German astronomer Max Wolf, director of the Landessternwarte Heidelberg-Königstuhl observatory of the University of Heidelberg, on a new and novel design, inspired by Wallace W. Atwood's work at the Chicago Academy of Sciences and by the ideas of Walther Bauersfeld and Rudolf Straubel at Zeiss; the result was a planetarium design which would generate all the necessary movements of the stars and planets inside the optical projector, would be mounted centrally in a room, projecting images onto the white surface of a hemisphere. In August 1923, the first Zeiss planetarium projected images of the night sky onto the white plaster lining of a 16 m hemispherical concrete dome, erected on the roof of the Zeiss works; the first official public showing was at the Deutsches Museum in Munich on October 21, 1923.
When Germany was divided into East and West Germany