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Mercator projection

The Mercator projection is a cylindrical map projection presented by Flemish geographer and cartographer Gerardus Mercator in 1569. It became the standard map projection for navigation because of its unique property of representing any course of constant bearing as a straight segment; such a course, known as a rhumb or, mathematically, a loxodrome, is preferred by navigators because the ship can sail in a constant compass direction to reach its destination, eliminating difficult and error-prone course corrections. Linear scale is constant on the Mercator in every direction around any point, thus preserving the angles and the shapes of small objects and fulfilling the conditions of a conformal map projection; as a side effect, the Mercator projection inflates the size of objects away from the equator. This inflation starts infinitesimally, but accelerates with latitude to become infinite at the poles. So, for example, landmasses such as Greenland and Antarctica appear far larger than they are relative to landmasses near the equator, such as Central Africa.

There is some controversy over the origins of the Mercator. German polymath Erhard Etzlaub engraved miniature "compass maps" of Europe and parts of Africa that spanned latitudes 0°–67° to allow adjustment of his portable pocket-size sundials; the projection found on these maps, dating to 1511, was stated by Snyder in 1987 to be the same projection as Mercator's. However, given the geometry of a sundial, these maps may well have been based on the similar central cylindrical projection, a limiting case of the gnomonic projection, the basis for sundial. Snyder amends his assessment to "a similar projection" in 1994. Joseph Needham, a historian of China, wrote that the Chinese developed the Mercator projection hundreds of years before Mercator did, using it in star charts during the Song Dynasty. However, this was a simple, common, case of misidentification; the projection in use was the equirectangular projection. Portuguese mathematician and cosmographer Pedro Nunes first described the mathematical principle of the loxodrome and its use in marine navigation.

In 1537, he proposed constructing a nautical atlas composed of several large-scale sheets in the cylindrical equidistant projection as a way to minimize distortion of directions. If these sheets were brought to the same scale and assembled, they would approximate the Mercator projection. In 1569, Gerhard Kremer, known by his trade name Gerardus Mercator, announced a new projection by publishing a large planispheric map measuring 202 by 124 cm and printed in eighteen separate sheets. Mercator titled the map Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendata: "A new and augmented description of Earth corrected for the use of sailors"; this title, along with an elaborate explanation for using the projection that appears as a section of text on the map, shows that Mercator understood what he had achieved and that he intended the projection to aid navigation. Mercator never explained the method of construction. Various hypotheses have been tendered over the years, but in any case Mercator's friendship with Pedro Nunes and his access to the loxodromic tables Nunes created aided his efforts.

English mathematician Edward Wright published the first accurate tables for constructing the projection in 1599 and, in more detail, in 1610, calling his treatise "Certaine Errors in Navigation". The first mathematical formulation was publicized around 1645 by a mathematician named Henry Bond. However, the mathematics involved were developed but never published by mathematician Thomas Harriot starting around 1589; the development of the Mercator projection represented a major breakthrough in the nautical cartography of the 16th century. However, it was much ahead of its time, since the old navigational and surveying techniques were not compatible with its use in navigation. Two main problems prevented its immediate application: the impossibility of determining the longitude at sea with adequate accuracy and the fact that magnetic directions, instead of geographical directions, were used in navigation. Only in the middle of the 18th century, after the marine chronometer was invented and the spatial distribution of magnetic declination was known, could the Mercator projection be adopted by navigators.

Despite those position-finding limitations, the Mercator projection can be found in many world maps in the centuries following Mercator's first publication. However, it did not begin to dominate world maps until the 19th century, when the problem of position determination had been solved. Once the Mercator became the usual projection for commercial and educational maps, it came under persistent criticism from cartographers for its unbalanced representation of landmasses and its inability to usefully show the polar regions; the criticisms leveled against inappropriate use of the Mercator projection resulted in a flurry of new inventions in the late 19th and early 20th century directly touted as alternatives to the Mercator. Due to these pressures, publishers reduced their use of the projection over the course of the 20th century. However, the advent of Web mapping gave the projection an abrupt resurgence in the form of the Web Mercator projection. Today, the Mercator can still be found in marine charts, occasional world maps, Web mapping service, but commercial atlases have abandoned it, wall maps of the world can be found in many alternative projections.

Google Maps, which relied on it since 2005, still uses it for local-area maps but dropped the projection from desktop platforms in 2017 for maps that are zoomed out of local areas. Many other online mapping services still use the Web Mercator; as in all cylindrical projections, pa

Queen Anne, Seattle

Queen Anne Hill is an affluent neighborhood and geographic feature in Seattle, northwest of downtown. The neighborhood sits on the highest named hill with a maximum elevation of 456 feet, it covers an area of 7.3 square kilometers, has a population of about 28,000. Queen Anne is bordered by Belltown to the south, Lake Union to the east, the Lake Washington Ship Canal to the north and Interbay to the west; the hill became a popular spot for the city's early economic and cultural elite to build their mansions, the name derives from the architectural style typical of many of the early homes. Queen Anne is bounded on the north by the Fremont Cut of the Lake Washington Ship Canal, beyond, Fremont; as a neighborhood toponym, Queen Anne may include Lower Queen Anne known as Uptown, the area at the southern base of the hill, just north and west of Seattle Center. Whether or not Lower Queen Anne is considered a separate neighborhood matters in setting Queen Anne's southern boundary, either West Mercer Street or Denny Way.

Queen Anne can be reached from Interstate 5 via the Mercer Street Exit. The neighborhood's main thoroughfares are Gilman Drive West, 3rd Avenue West, Queen Anne Avenue North, Boston Street, a set of streets, collectively known as Queen Anne Boulevard, that loop around the crown of the hill and reflect a comprehensive boulevard design in the style of the Olmsted Brothers architectural firm; the design was never executed, but it remains part of the Seattle Parks System. While Queen Anne stands out in Seattle geography due to its proximity to downtown and three television broadcast towers, the highest point in the city, 520 feet above sea level, is in West Seattle. Queen Anne slopes are home to seven of the twenty steepest streets in the city and 120 pedestrian staircases. Including the sub-neighborhoods of North Queen Anne, West Queen Anne, East Queen Anne and Lower Queen Anne, Queen Anne has 19,000 households and a total population of about 36,000. Queen Anne is disproportionately populated by unmarried, young adults.

The population is better educated than Seattle as a whole. The Vashon Glacier carved Queen Anne Hill's topography more than 13,000 years ago, human habitation in the area began some 3000 years ago; when White settlers arrived in the mid-19th century, the Duwamish tribe maintained a seasonal presence in and around Queen Anne. White settlement of Queen Anne stemmed from the arrival of the Denny Party at West Seattle's Alki Point in November 1851. In 1853, David Denny staked a claim to 320 acres of land the Duwamish called baba'kwoh, known today as Lower Queen Anne, bounded by Elliott Bay to the west, Lake Union to the east, Mercer Street to the north, Denny Way to the south. Denny called the area "Potlach Meadows". Development of the hill, called at various times North Seattle, Galer Hill, Eden Hill, was slow. An 1875 windstorm flattened thousands of trees on Queen Anne, making the dense forest more appealing for settlement; the hill began to be called "Queen Anne" by 1885, after the Queen Anne style houses that dominated the area.

The arrival of the Northern Pacific Railway and the Seattle, Lake Shore and Eastern Railway, the Great Seattle Fire of 1889, the opening of three cable car lines to the top of the hill, further encouraged residential and business development. The 1917 opening of the Lake Washington Ship Canal, the Fremont and Ballard Bridges over it, made the area more appealing for maritime and timber industries, connected Queen Anne with communities to the north. On the south side of the hill, the 1927 completion of a Civic Center on David Denny's Potlach Meadows land brought residents from all over the city to Queen Anne for concerts and sporting events; the first television broadcast in the Pacific Northwest originated from KRSC's facilities at 3rd Avenue N. at Galer Street in 1948. In 1949, KING-TV bought KRSC. Three years KOMO-TV installed its own tower, KIRO followed suit in 1958. "The 1962 Seattle World's Fair was the most transformational single event in the history of Queen Anne", according to historians Florence K. Lentz and Mimi Sheridan.

Named the Century 21 Exposition, the fair expanded on existing Civic Center infrastructure on the old baba'kwoh swale. After the fair, the grounds became the Seattle Center, home to the Space Needle, Pacific Science Center, Experience Music Project, Science Fiction Museum and Hall of Fame, the north terminal of the Seattle monorail and KeyArena; the Seattle SuperSonics began playing at the then-Seattle Center Coliseum in 1967. The Seattle Thunderbirds hockey team began play next door at the Mercer Street Arena in 1977; the Seattle Storm basketball team began play at KeyArena in 2000. As late as 1964, the area had a large enough population of families with children to motivate opening McClure Middle School, but by 1981 a decline in such families led the school system to close Queen Anne High School, North Queen Anne Elementary School, West Queen Anne Elementary School. Assistant United States Attorney Thomas C. Wales was shot in his home in the Queen Anne neighborhood on October 11, 2001, dying the next day of his wounds.

The murder remains unsolved. Queen Anne is home to 29 official Seattle landmarks, including 12 historic houses. A group of residences on 14th Avenue West, built between 1890 and 1910, include one of the few remaining Queen Anne style h

1785 in science

The year 1785 in science and technology involved some significant events. Dunsink Observatory established near Dublin. January 7 – Frenchman Jean-Pierre Blanchard and American John Jeffries travel from Dover, England to Calais, France in a gas balloon, becoming the first to cross the English Channel by air. January 19 – Richard Crosbie flies in a hot air balloon across Dublin, the first ascent in Ireland. Antoine François and Étienne Louis Geoffroy publish Entomologia Parisiensis, Catalogus insectorum quae in agro Parisiensi reperiuntur.... John Stuart, 3rd Earl of Bute, publishes Botanical Tables, containing the different families of British plants. March 7–July – James Hutton's Theory of the Earth is first presented, at the Royal Society of Edinburgh. André Michaux is sent by the French government to North America to look for new plants; the Marquis de Condorcet publishes Essai sur l'application de l'analyse á la probabilité des décisions rendues á la pluralité des voix including his voting paradox, the Condorcet method of voting and his jury theorem.

William Withering publishes some of its Medical Uses. London Hospital Medical College opens as England's first chartered medical school. Lionel Lukin patents a rescue lifeboat in Great Britain. Approximate date – American inventor Oliver Evans erects a automated flour mill capable of operating continuously through the pioneering use of bulk material handling devices including bucket elevators, conveyor belts, Archimedean screws at Greenbank Mill, in New Castle County, Delaware – "He invented the modern science of handling materials." Copley Medal: William Roy January 15 – William Prout, chemist February 26 – Anna Sundström, chemist March 17 – Ellen Hutchins, Irish botanist March 22 – Adam Sedgwick, geologist April 26 – John James Audubon, illustrator July 6 – William Jackson Hooker, botanist January 23 – Matthew Stewart, Scottish mathematician June 2 – Jean Paul de Gua de Malves, French mathematician November 16 – Johan Gottschalk Wallerius, Swedish chemist and mineralogist December 12 – Edmé-Louis Daubenton, French naturalist Pierre Le Roy, French clockmaker Saverio Manetti, Italian natural historian undated – Faustina Pignatelli, Italian mathematician