1.
Trigonometry
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Trigonometry is a branch of mathematics that studies relationships involving lengths and angles of triangles. The field emerged in the Hellenistic world during the 3rd century BC from applications of geometry to astronomical studies, Trigonometry is also the foundation of surveying. Trigonometry is most simply associated with planar right-angle triangles, thus the majority of applications relate to right-angle triangles. One exception to this is spherical trigonometry, the study of triangles on spheres, surfaces of constant positive curvature, Trigonometry on surfaces of negative curvature is part of hyperbolic geometry. Trigonometry basics are often taught in schools, either as a course or as a part of a precalculus course. Sumerian astronomers studied angle measure, using a division of circles into 360 degrees, the ancient Nubians used a similar method. In 140 BC, Hipparchus gave the first tables of chords, analogous to modern tables of sine values, in the 2nd century AD, the Greco-Egyptian astronomer Ptolemy printed detailed trigonometric tables in Book 1, chapter 11 of his Almagest. Ptolemy used chord length to define his trigonometric functions, a difference from the sine convention we use today. The modern sine convention is first attested in the Surya Siddhanta and these Greek and Indian works were translated and expanded by medieval Islamic mathematicians. By the 10th century, Islamic mathematicians were using all six trigonometric functions, had tabulated their values, at about the same time, Chinese mathematicians developed trigonometry independently, although it was not a major field of study for them. At the same time, another translation of the Almagest from Greek into Latin was completed by the Cretan George of Trebizond, Trigonometry was still so little known in 16th-century northern Europe that Nicolaus Copernicus devoted two chapters of De revolutionibus orbium coelestium to explain its basic concepts. Driven by the demands of navigation and the growing need for maps of large geographic areas. Bartholomaeus Pitiscus was the first to use the word, publishing his Trigonometria in 1595, gemma Frisius described for the first time the method of triangulation still used today in surveying. It was Leonhard Euler who fully incorporated complex numbers into trigonometry, the works of the Scottish mathematicians James Gregory in the 17th century and Colin Maclaurin in the 18th century were influential in the development of trigonometric series. Also in the 18th century, Brook Taylor defined the general Taylor series, if one angle of a triangle is 90 degrees and one of the other angles is known, the third is thereby fixed, because the three angles of any triangle add up to 180 degrees. The two acute angles therefore add up to 90 degrees, they are complementary angles, the shape of a triangle is completely determined, except for similarity, by the angles. Once the angles are known, the ratios of the sides are determined, if the length of one of the sides is known, the other two are determined. Sin A = opposite hypotenuse = a c, Cosine function, defined as the ratio of the adjacent leg to the hypotenuse
2.
Surveying
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Surveying or land surveying is the technique, profession, and science of determining the terrestrial or three-dimensional position of points and the distances and angles between them. A land surveying professional is called a land surveyor, Surveyors work with elements of geometry, trigonometry, regression analysis, physics, engineering, metrology, programming languages and the law. Surveying has been an element in the development of the environment since the beginning of recorded history. The planning and execution of most forms of construction require it and it is also used in transport, communications, mapping, and the definition of legal boundaries for land ownership. It is an important tool for research in other scientific disciplines. Basic surveyance has occurred since humans built the first large structures, the prehistoric monument at Stonehenge was set out by prehistoric surveyors using peg and rope geometry. In ancient Egypt, a rope stretcher would use simple geometry to re-establish boundaries after the floods of the Nile River. The almost perfect squareness and north-south orientation of the Great Pyramid of Giza, built c.2700 BC, the Groma instrument originated in Mesopotamia. The mathematician Liu Hui described ways of measuring distant objects in his work Haidao Suanjing or The Sea Island Mathematical Manual, the Romans recognized land surveyors as a profession. They established the basic measurements under which the Roman Empire was divided, Roman surveyors were known as Gromatici. In medieval Europe, beating the bounds maintained the boundaries of a village or parish and this was the practice of gathering a group of residents and walking around the parish or village to establish a communal memory of the boundaries. Young boys were included to ensure the memory lasted as long as possible, in England, William the Conqueror commissioned the Domesday Book in 1086. It recorded the names of all the owners, the area of land they owned, the quality of the land. It did not include maps showing exact locations, abel Foullon described a plane table in 1551, but it is thought that the instrument was in use earlier as his description is of a developed instrument. Gunters chain was introduced in 1620 by English mathematician Edmund Gunter and it enabled plots of land to be accurately surveyed and plotted for legal and commercial purposes. Leonard Digges described a Theodolite that measured horizontal angles in his book A geometric practice named Pantometria, joshua Habermel created a theodolite with a compass and tripod in 1576. Johnathon Sission was the first to incorporate a telescope on a theodolite in 1725, in the 18th century, modern techniques and instruments for surveying began to be used. Jesse Ramsden introduced the first precision theodolite in 1787 and it was an instrument for measuring angles in the horizontal and vertical planes
3.
Board of Ordnance
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The Board of Ordnance was a British government body. Established in the Tudor period, it had its headquarters in the Tower of London, the Board also maintained and directed the Artillery and Engineer corps, which it founded in the eighteenth century. By the nineteenth century, the Board of Ordnance was second in only to HM Treasury among government departments. The Board lasted until 1855, at which point it was disbanded, the introduction of gunpowder to Europe led to innovations in offensive weapons, such as cannon, and defences, such as fortifications. From the 1320s a member of the Royal Household, the Keeper of the Privy Wardrobe in the Tower of London, became responsible for the procurement, storage. His office and main arsenal were located in the White Tower and this Privy Wardrobe in the Tower grew, both in size and significance, after the start of the Hundred Years War. In the following century, the influence of the Privy Wardrobe and its staff receded, a distinct Office of Ordnance began to establish itself at the Tower, staffed in the 1460s by a Master, a Clerk and a Yeoman. In the 1540s, under Henry VIII, the Ordnance Office was expanded, new officers were appointed and their principal duties clarified. In 1671, the Ordnance Office took over the work of the Office of Armoury at the Tower, at this time the Ordnance Office began to take on oversight of the nations forts and fortifications. In 1683, by now known as the Board of Ordnance. These detailed Instructions continued, with little change, to provide the working framework for the Board. From the mid-16th century onwards, the Board of Ordnance had six principal officers, merbury was present at the Siege of Harfleur and at the Battle of Agincourt. By 1450 Master of Ordnance was a permanent appointment, firmly based at the Tower of London, until 1544 the Master had generally managed the day-to-day activities of the Ordnance Office. Thereafter the Lieutenant had day-to-day oversight of the Boards activities, while Master had more the role of a statesman, from the seventeenth century through till 1828 the Master-General routinely had a seat in Cabinet, and thus served as de facto principal military adviser to the government. Some of the most illustrious soldiers of their generation served as Master-General, Marlborough, Cadogan, Cornwallis, Hastings, Wellington, from its earliest years, the Ordnance Office was staffed by a large number of Clerks to manage its substantial administrative functions. A number of officials reported to the board, including furbishers, proofmasters, keepers and fireworkers. Two appointments stand out, as they were appointed by Letters Patent under the Great Seal of the Realm, namely the Master Gunner of England and these were the senior technicians on the staff. The Treasurer of the Ordnance was another important officer of the department and this office was instituted in 1670, the post was consolidated with several others in 1836 to form that of Paymaster-General
4.
Figure of the Earth
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The expression figure of the Earth has various meanings in geodesy according to the way it is used and the precision with which the Earths size and shape is to be defined. The actual topographic surface is most apparent with its variety of land forms and this is, in fact, the surface on which actual Earth measurements are made. The topographic surface is generally the concern of topographers and hydrographers, the Pythagorean concept of a spherical Earth offers a simple surface that is mathematically easy to deal with. Many astronomical and navigational computations use it as a representing the Earth. The idea of a planar or flat surface for Earth, however, is sufficient for surveys of small areas, as the local topography is far more significant than the curvature. Plane-table surveys are made for small areas, and no account is taken of the curvature of the Earth. A survey of a city would likely be computed as though the Earth were a surface the size of the city. For such small areas, exact positions can be determined relative to each other without considering the size, in the mid- to late 20th century, research across the geosciences contributed to drastic improvements in the accuracy of the figure of the Earth. The primary utility of this improved accuracy was to provide geographical and gravitational data for the guidance systems of ballistic missiles. This funding also drove the expansion of geoscientific disciplines, fostering the creation, the models for the figure of the Earth vary in the way they are used, in their complexity, and in the accuracy with which they represent the size and shape of the Earth. The simplest model for the shape of the entire Earth is a sphere, the Earths radius is the distance from Earths center to its surface, about 6,371 kilometers. The concept of a spherical Earth dates back to around the 6th century BC, the first scientific estimation of the radius of the earth was given by Eratosthenes about 240 BC, with estimates of the accuracy of Eratosthenes’s measurement ranging from 2% to 15%. The Earth is only approximately spherical, so no single value serves as its natural radius, distances from points on the surface to the center range from 6,353 km to 6,384 km. Several different ways of modeling the Earth as a sphere each yield a mean radius of 6,371 kilometers, regardless of the model, any radius falls between the polar minimum of about 6,357 km and the equatorial maximum of about 6,378 km. The difference 21 kilometers correspond to the polar radius being approximately 0. 3% shorter than the equator radius, since the Earth is flattened at the poles and bulges at the equator, geodesy represents the shape of the earth with an oblate spheroid. The oblate spheroid, or oblate ellipsoid, is an ellipsoid of revolution obtained by rotating an ellipse about its shorter axis and it is the regular geometric shape that most nearly approximates the shape of the Earth. A spheroid describing the figure of the Earth or other body is called a reference ellipsoid. The reference ellipsoid for Earth is called an Earth ellipsoid, an ellipsoid of revolution is uniquely defined by two numbers, two dimensions, or one dimension and a number representing the difference between the two dimensions
5.
William Roy
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Major-General William Roy FRS, AS was a Scottish military engineer, surveyor, and antiquarian. He was an innovator who applied new scientific discoveries and newly emerging technologies to the accurate geodetic mapping of Great Britain and it was Roys advocacy and leadership that led to the creation of the Ordnance Survey in 1791, the year after his death. His technical work in the establishment of a surveying baseline won him the Copley Medal in 1785 and his maps and drawings of Roman archaeological sites in Scotland were the first accurate and systematic study of the subject, and have not been improved upon even today. Roy was a Fellow of the Royal Society and a member of the Society of Antiquaries of London, close The early years of the Ordnance Survey. Hewitt Map of a Nation, a biography of the Ordnance Survey, owen & Pilbeam Ordnance Survey, map makers to Britain since 1791. Seymour A History of the Ordnance Survey, porter History of the Corps of Royal Engineers. Roy was born at Milton Head in Carluke Parish in South Lanarkshire on 4 May 1726 and his father was a factor in the service of the Gordons/Hamiltons of Hallcraig, as well as an elder of the Kirk. His grandfather had held a position as factor, and his uncle acted in that capacity for the Lockharts of Lee. Thus Roy grew up in an environment where making land surveys and he was educated in the parish school and Lanark Grammar School. But there is no record of a further education such as that enjoyed by his younger brother James, the next few years of his life are poorly documented. Roy was certainly associated with the board by 1746, for he was the author of a map of Culloden made soon after the battle. Roy maintained his connections to his birthplace and the living there. A servant for the Lockharts of Lee recalled his visits there over time and she noted that at first he would dine in the servants hall, in later years he would dine with the family, and later still he would be seated at the right hand of the Laird. Eventually there were six teams conducting surveys by traverses of the country with the objects to the side of the line recorded by sketches and compass directions. The Highlands were covered by 1752, but the survey was extended to the lowlands for another three years, until 1755, when most of the surveyors were posted to war stations. In the introduction to the 1885 account of the measurement of the Hounslow baseline Roy writes that the map remained in an unfinished state, and is to be considered as a magnificent military sketch rather than a very accurate map of a country. It would have completed, and many of its imperfections no doubt remedied. It is now possible to view the map online, in the same year the engineers of the board were formed into the Corps of Engineers
6.
William Mudge
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William Mudge was an English artillery officer and surveyor, born in Plymouth, an important figure in the work of the Ordnance Survey. William Mudge was a son of Dr. John Mudge of Plymouth, by his wife, and grandson of Zachariah Mudge. He entered the Royal Military Academy, Woolwich on 17 April 1777, and while he was there his godfather, Samuel Johnson, paid him a visit, and gave him a guinea and a book. On 9 July 1779 he received a commission as lieutenant in the Royal Artillery. He was promoted first lieutenant on 16 May 1781, on his return home he was stationed at the Tower of London, and studied the higher mathematics under Charles Hutton, amusing himself in his spare time with the construction of clocks. He was appointed in 1791 to the Ordnance Trigonometrical Survey, of which he was promoted to be director on the death of Colonel Edward Williams in 1798 and he was elected a Fellow of the Royal Society the same year. Around 1800 Dunnose was taken as a point for a triangulation of Great Britain, in which Mudge measured a section of the meridional arc running up into Yorkshire. The triangulation was conducted in 1801 and 1802, Mudge was promoted brevet major on 25 September 1801, regimental major 14 September 1803, and lieutenant-colonel 20 July 1804. While at the head of the survey he resided first, until 1808, at the Tower of London, and afterwards at 4 Holles Street, London, in 1813 it was determined to extend the Meridian arc into Scotland. Mudge superintended the arrangement of the work, and in some cases took the actual measurement. On the extension of the English arc of the meridian into Scotland, on 4 June 1813 Mudge was promoted brevet-colonel, and on 20 December 1814 regimental colonel. In 1817 he received from the University of Edinburgh the degree of LL. D, in 1818 he travelled in France for the benefit of his health, and on his return was appointed a commissioner of the new board of longitude. In 1819 Frederick VI of Denmark visited the survey operations at Bagshot Heath, in May of this year he began the survey of Scotland, and on 12 August he was promoted major-general. He died on 17 April 1820, ‘An Account of the Trigonometrical Survey carried on by Order of the Master-General of H. M. First published in, and now revised from, the “Philosophical Transactions, ” by William Mudge, the Second Volume, continued from 1797 to the end of 1799, by William Mudge. The Third Volume, an Account of the Trigonometrical Survey in 1800,1801,1803 to 1809, by William Mudge and Thomas Colby, ‘Sailing Directions for the N. E. N. and N. W. Coasts of Ireland, partly drawn up by William Mudge, completed by G. A. Fraser, Mudge married Margaret Jane, third daughter of Major-general Williamson, R. A. who survived him four years. He left a daughter, two sons in the engineers, one in the Royal Artillery, and one in the Royal Navy
7.
Thomas Frederick Colby
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Thomas Frederick Colby FRS FRSE FGS FRGS, was a British major-general and director of the Ordnance Survey. A Fellow of the Royal Astronomical Society and Royal Society, Colby was one of the geographers of his time. An officer in the Royal Engineers, Colby overcame the loss of one hand in an accident to begin in 1802 a lifelong connection with the Ordnance Survey. His most important work was the Survey of Ireland and he began planning this enormous enterprise in 1824 and directed it until 1846, in which year the final maps made by the survey were almost ready for issue. He was the inventor of the Colby Bar, a used in base-measurements. He was the eldest child of Major Thomas Colby, Royal Marines and he was born at St. Margarets-next-Rochester on 1 September 1784. He was brought up by his fathers sisters at Rhosygilwen, near Cilgerran, Pembrokeshire, West Wales and he went on to the Royal Military Academy, Woolwich, and passed out for the Royal Engineers while still 16. Colby attracted the notice of Major William Mudge, director of the Ordnance Survey and his first task was sector observations made at Dunnose, Isle of Wight in the summer of 1802. Later he was selecting trigonometrical stations on the mountains in South Wales, the publication of the maps themselves was suspended during the Napoleonic wars. In July 1809, Mudge was appointed lieutenant governor of the Royal Military Academy, Woolwich, in that and the following year Colby and his chief assistant, James Gardner, were selecting stations in the south-west of Scotland, and observing from them by theodolite. Biot and Colby fell out, however, Colby later accompanied General Mudge to Dunkirk, and took part in the observations made, with Biot and François Arago, using Jesse Ramsdens sector, which was set up in Dunkirk arsenal. In 1819 Colby was again engaged in Scotland, the work beginning, early in May, on Corrie Habbie, Banff. Colby was made LL. D. of the University of Aberdeen, early in 1820 General Mudge died, and the Duke of Wellington appointed Colby to succeed him at the head of the Ordnance Survey. On 13 April 1820 Colby became a Fellow of the Royal Society, later in the same year Lord Melville nominated him to a seat on the Board of Longitude, which he retained until it was dissolved in 1828. He also became an associate and then a member of the Institution of Civil Engineers. At this time living in London, he was among the proprietors of the London Institute and he was also one of the founders of the Royal Astronomical Society, and with Mark Beaufoy, Olinthus Gregory, Edward Troughton, and others, drew up its rules. The results were published in Philosophical Transactions for 1828, fresnels new compound lenses were used for the observations across the English Channel. Colby gave his notes on them to his friend Robert Stevenson, in 1824 Colby and the Ordnance Survey were given the task of surveying Ireland
8.
Alexander Ross Clarke
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He was an officer of the Royal Engineers employed on the Ordnance Survey. The basic sources of material on Clarke are the two articles by Charles Close, one of the Directors of the Ordnance Survey, the first was an article for the Royal Engineers Journal and the second, a revised and expanded version, appeared in the Empire Survey Review. Much of Closes material is incorporated in the web page REubique along with details of his career and further information communicated by one of Clarkes living descendants. Other sources of information are to be found in the Times of London, two recent histories of the Ordnance Survey include information on Clarke, Owen and Pilbeam, and Seymour. Clarke was born in Reading, Berkshire, England on 16 December 1828, the parents, David and Eliza, were back in England by 1834 but they soon moved up to Davids family home at Eriboll in the far north of Scotland. The school teaching there was primitive but effective, anyway he learned Latin and mathematics. Close adds that The mathematics that was kicked into him determined his career in after life. David Clarke and his moved to London, before 1846, and eventually settled at 35 Devonshire Place. His wife, Eliza Ann, died in 1887 and it was from this London address that Alexander Clarke, at the age of seventeen in 1846, applied to the Royal Military Academy, Woolwich as a Gentleman Cadet. Clarke was very unprepared for the examination, having left a space of only three weeks for revision, and he was placed bottom of the list of candidates. At Woolwich he would undergo basic training and formal teaching in subjects such as mathematics. Clarke excelled at his studies and he passed out first, with the reputation of being a capable young man. He was commissioned as a lieutenant in the Royal Engineers on 1 October 1847. After his commissioning, Clarke attended the Young Officers Course at the Royal School of Military Engineering at Chatham and he was promoted to the rank of Lieutenant on 11 July 1849 at the end of that course. Before Clarke could make progress on the calculation of the triangulation, the nature of the posting is not recorded but it had one happy outcome. Clarke met, and married, Frances Maria, youngest daughter of Colonel Matthew C, Superintendent Hall retired in 1854 and Yolland, the most competent member of the Survey, was passed over in favour of Colonel Henry James. Yolland resigned immediately and Clarke was the only qualified candidate for the analysis of the triangulation, the magnitude of this task is discussed below. The report was accomplished by 1858, a short period of time
9.
Retriangulation of Great Britain
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The aim was to replace the original triangulation of Britain, known as the Principal Triangulation, which had been performed between 1783 and 1853, with a more modern and accurate triangulation. It was commenced in 1935 by the new Director General of the Ordnance Survey, the effort was directed by the cartographer and mathematician Martin Hotine, head of the Trigonometrical and Levelling Division, who planned the operation in a manner similar to a military campaign. Every detail of the operation and measurements was carefully specified in advance to attempt to produce the most accurate measurements possible, given available technology. Erecting new trig points and making measurements frequently required materials and instruments to be carried on foot, up hills and mountains and to isolated islands, the calculations were constrained, it was hoped to minimise the shifts from the coordinates based on the old triangulation. At eleven primary trig points from Dunnose on the Isle of Wight north to Great Whernside in Yorkshire the new lat-lons were adjusted to stay within a metre of the old ones. Once the new Latitude and Longitude of those points were fixed the calculated location of every other point in the triangulation was based on them. The results of the retriangulation were used to create the British national grid system which became the basis of the Ordnance Surveys new maps. The history of the retriangulation of Great Britain 1935-1962, Ordnance Survey, map makers to Britain since 1791. Freely available online at the Ordnance Survew, Owen and Pilbeam Seymour, a History of the Ordnance Survey
10.
Jacobite rising of 1745
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The Jacobite rising of 1745 was the attempt by Charles Edward Stuart to regain the British throne for the exiled House of Stuart. The rising occurred during the War of the Austrian Succession when most of the British Army was on the European continent, the march south began with an initial victory at Prestonpans near Edinburgh. The Jacobite army, now in bold spirits, marched onwards to Carlisle, the Battle of Culloden ended with the final defeat of the Jacobite cause, and with Charles Edward Stuart fleeing with a price on his head, before finally sailing to France. The Glorious Revolution of 1688–89 resulted in the Roman Catholic Stuart king, James II of England and VII of Scotland, James daughter and her husband, who was also Jamess nephew, ascended the British throne as joint sovereigns William and Mary. In 1690 Presbyterianism was established as the religion of Scotland. The Act of Settlement 1701 settled the succession of the English throne on the Protestant House of Hanover, the Scottish Act of Security 1704 required that Queen Annes successor be Protestant, and the Act of Union 1707 applied the Act of Settlement to Scotland. With the death of Queen Anne in 1714, the Elector of Hanover, George I, James IIs son, James Francis Edward Stuart, the Old Pretender, attempted to gain the British throne in 1715 but failed to do so. The accession of George I ushered in the Whig supremacy, with the Tories deprived of all political power, George II succeeded his father in 1727. In February 1742 Sir Robert Walpole resigned as Prime Minister after nearly 21 years, thereafter, the Whig Henry Pelham was Prime Minister until 1754. In 1743 war broke out between Britain and France, as part of the larger War of the Austrian Succession and it was signed by the Duke of Beaufort, Lord Barrymore, Lord Orrery, Sir Watkin Williams Wynn, Sir John Hynde Cotton and Sir Robert Abdy. Amelot replied that the French government would need proof of English support for Jacobitism before it could act. The Tory leaders had requested 10,000 French soldiers and arms for 10,000 of the officers on half pay and unemployed soldiers. The French were to land in Maldon in Essex, a section of coast not patrolled by the Royal Navy, obviating a crossing of the River Thames and counting on support from Jacobite sentiment there. They advised that Maurice of Saxony should command the French army because he was known to most of them and was a Protestant. A parallel expeditionary force for a Scottish landing under the command of Lord Marischal was requested as well, James Butler, Louis XVs Master of Horse, toured England ostensibly for purchasing bloodstock but in reality to gauge the health of Jacobitism in England. Before he left for England the French king briefed him personally to assure the Tory leaders that all of their demands would be met and he reported back that they showed great zeal for a revolution. John Sample, a spy for Walpole, told the Duke of Newcastle that plans for a French invasion had been orchestrated by Wynn, Butler returned to France in October and had an audience with Louis XV, who said he was satisfied. The next month Amelot told Sempill officially that Louis XV was resolved to restore the House of Stuart, the Declaration of King James was signed by James Francis Edward Stuart on 23 December 1743 and was to be published in the event of a successful French landing
11.
Scottish Highlands
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The Highlands are a historic region of Scotland. Culturally, the Highlands and the Lowlands diverged from the later Middle Ages into the modern period, the term is also used for the area north and west of the Highland Boundary Fault, although the exact boundaries are not clearly defined, particularly to the east. The Great Glen divides the Grampian Mountains to the southeast from the Northwest Highlands, the Scottish Gaelic name of A Ghàidhealtachd literally means the place of the Gaels and traditionally, from a Gaelic-speaking point of view, includes both the Western Isles and the Highlands. The area is sparsely populated, with many mountain ranges dominating the region. At 9.1 per km2 in 2012, the density in the Highlands and Islands is less than one seventh of Scotlands as a whole, comparable with that of Bolivia, Chad. The Highland Council is the body for much of the Highlands. However, the Highlands also includes parts of the areas of Aberdeenshire, Angus, Argyll and Bute, Moray, North Ayrshire, Perth & Kinross, Stirling. The Scottish highlands is the area in the British Isles to have the Taiga biome as it features concentrated populations of Scots pine forest. Between the 15th century and the 20th century, the area differed from most of the Lowlands in terms of language. In Scottish Gaelic, the region is known as the Gàidhealtachd, because it was traditionally the Gaelic-speaking part of Scotland, the terms are sometimes used interchangeably but have different meanings in their respective languages. Scottish English is the predominant language of the area today, though Highland English has been influenced by Gaelic speech to a significant extent, historically, the Highland line distinguished the two Scottish cultures. Most of this legislation was repealed by the end of the 18th century as the Jacobite threat subsided, there was soon a rehabilitation of Highland culture. Tartan was adopted for Highland regiments in the British Army, which poor Highlanders joined in large numbers in the era of the Revolutionary and Napoleonic wars. Tartan had largely abandoned by the ordinary people of the region, but in the 1820s, tartan and the kilt were adopted by members of the social elite, not just in Scotland. The international craze for tartan, and for idealising a romanticised Highlands, was set off by the Ossian cycle, individual clan tartans were largely designated in this period and they became a major symbol of Scottish identity. The period of the Napoleonic wars brought prosperity, optimism, the economy grew thanks to wages paid in industries such as kelping, fisheries, and weaving, as well as large-scale infrastructure spending such as the Caledonian Canal project. On the East Coast, farmlands were improved, and high prices for cattle brought money to the area, Service in the Army was also attractive to young men from the Highlands, who sent pay home and retired there with their army pensions. This prosperity ended after 1815, and long-term negative factors began to undermine the position of the poor tenant farmers, who typically rented a few acres
12.
French Academy of Sciences
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The French Academy of Sciences is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at the forefront of developments in Europe in the 17th and 18th centuries. Currently headed by Sébastien Candel, it is one of the five Academies of the Institut de France, the Academy of Sciences makes its origin to Colberts plan to create a general academy. He chose a group of scholars who met on 22 December 1666 in the Kings library. The first 30 years of the Academys existence were relatively informal, in contrast to its British counterpart, the Academy was founded as an organ of government. The Academy was expected to remain apolitical, and to avoid discussion of religious, on 20 January 1699, Louis XIV gave the Company its first rules. The Academy received the name of Royal Academy of Sciences and was installed in the Louvre in Paris, following this reform, the Academy began publishing a volume each year with information on all the work done by its members and obituaries for members who had died. This reform also codified the method by which members of the Academy could receive pensions for their work, on 8 August 1793, the National Convention abolished all the academies. Almost all the old members of the previously abolished Académie were formally re-elected, among the exceptions was Dominique, comte de Cassini, who refused to take his seat. In 1816, the again renamed Royal Academy of Sciences became autonomous, while forming part of the Institute of France, in the Second Republic, the name returned to Académie des sciences. During this period, the Academy was funded by and accountable to the Ministry of Public Instruction, the Academy came to control French patent laws in the course of the eighteenth century, acting as the liaison of artisans knowledge to the public domain. As a result, academicians dominated technological activities in France, the Academy proceedings were published under the name Comptes rendus de lAcadémie des sciences. The Comptes rendus is now a series with seven titles. The publications can be found on site of the French National Library, in 1818 the French Academy of Sciences launched a competition to explain the properties of light. The civil engineer Augustin-Jean Fresnel entered this competition by submitting a new theory of light. Siméon Denis Poisson, one of the members of the judging committee, being a supporter of the particle-theory of light, he looked for a way to disprove it. The Poisson spot is not easily observed in every-day situations, so it was natural for Poisson to interpret it as an absurd result. However, the head of the committee, Dominique-François-Jean Arago, and he molded a 2-mm metallic disk to a glass plate with wax
13.
Royal Observatory, Greenwich
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The Royal Observatory, Greenwich is an observatory situated on a hill in Greenwich Park, overlooking the River Thames. It played a role in the history of astronomy and navigation. The observatory was commissioned in 1675 by King Charles II, with the stone being laid on 10 August. The site was chosen by Sir Christopher Wren and he appointed John Flamsteed as the first Astronomer Royal. The building was completed in the summer of 1676, the building was often called Flamsteed House, in reference to its first occupant. The scientific work of the observatory was relocated elsewhere in stages in the first half of the 20th century,1675 –22 June, Royal Observatory founded. 1675 –10 August, construction began,1714 Longitude Act established the Board of Longitude and Longitude rewards. The Astronomer Royal was, until the Board was dissolved in 1828,1767 Astronomer Royal Nevil Maskelyne began publication of the Nautical Almanac, based on observations made at the Observatory. 1833 Daily time signals began, marked by dropping a Time ball,1899 The New Physical Observatory was completed. 1924 Hourly time signals from the Royal Observatory were first broadcast on 5 February,1948 Office of the Astronomer Royal was moved to Herstmonceux. 1957 Royal Observatory completed its move to Herstmonceux, becoming the Royal Greenwich Observatory, the Greenwich site is renamed the Old Royal Observatory. Greenwich site is returned to its name, the Royal Observatory. The Ordnance Office was given responsibility for building the Observatory, with Moore providing the key instruments, Moore donated two clocks, built by Thomas Tompion, which were installed in the 20 foot high Octagon Room, the principal room of the building. They were of unusual design, each with a pendulum 13 feet in length mounted above the face, giving a period of four seconds. British astronomers have used the Royal Observatory as a basis for measurement. Four separate meridians have passed through the buildings, defined by successive instruments, subsequently, nations across the world used it as their standard for mapping and timekeeping. When the Airy circle became the reference for the meridian, the difference resulting from the change was considered enough to be neglected. When a new triangulation was done between 1936 and 1962, scientists determined that in the Ordnance Survey system the longitude of the international Greenwich meridian was not 0° and this old astronomical prime meridian has been replaced by a more precise prime meridian
14.
Paris Observatory
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The Paris Observatory is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world. Its historic building is to be found on the Left Bank of the Seine in central Paris, administratively, it is a grand établissement of the French Ministry of National Education, with a status close to that of a public university. Its missions include, research in astronomy and astrophysics, education, diffusion of knowledge to the public and it maintains a solar observatory at Meudon and a radio astronomy observatory at Nançay. It was also the home to the International Time Bureau until its dissolution in 1987 and its foundation lies in the ambitions of Jean-Baptiste Colbert to extend Frances maritime power and international trade in the 17th century. Louis XIV promoted its construction, which was started in 1667 and it thus predates by a few years the Royal Greenwich Observatory in England, which was founded in 1675. The architect of the Paris Observatory was Claude Perrault whose brother, Charles, was secretary to Colbert, optical instruments were supplied by Giuseppe Campani. The buildings were extended in 1730,1810,1834,1850, the last extension incorporates the spectacular Meridian Room designed by Jean Prouvé. The worlds first national almanac, the Connaissance des temps, was published by the observatory in 1679, in 1863, the observatory published the first modern weather maps. In 1882, a 33 cm astrographic lens was constructed, an instrument that catalysed what proved to be the over-ambitious international Carte du Ciel project. The Meudon great refractor was a 83 cm aperture refractor, which with September 20,1909 observations by E. M. Antoniadi helped disprove the Mars canals theory and it was a double telescope completed in 1891, with secondary having 62 cm aperture lens for photography. It was one of the largest active telescopes in Europe, the title of Director of the Observatory was officially given for the first time to César-François Cassini de Thury by a Royal brevet dated November 12,1771. However, the important role played by his grandfather and father in this institution during its first century actually gives them somewhat the role of director, a coronograph was in operation there for ten years, the dome was moved there from the Perrault building of the Observatoire de Paris. Nowadays, the AstroQueyras amateur astronomy association operates the facility, using a 60 cm telescope on loan from the Observatoire de Haute Provence, numerous asteroids have been discovered there. Paris Observatory, Encyclopaedia Britannica, Deluxe CDROM edition Aubin, D, the fading star of the Paris Observatory in the nineteenth century, astronomers urban culture of circulation and observation. History of the Bureau International de lHeure, polar Motion, Historical and Scientific problems. Paris Observatory Paris Observatory History Location in Paris Publications of the Observatoire de Paris in Gallica, the digital library of the BnF
15.
Royal Society
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Founded in November 1660, it was granted a royal charter by King Charles II as The Royal Society. The society is governed by its Council, which is chaired by the Societys President, according to a set of statutes and standing orders. The members of Council and the President are elected from and by its Fellows, the members of the society. As of 2016, there are about 1,600 fellows, allowed to use the postnominal title FRS, there are also royal fellows, honorary fellows and foreign members, the last of which are allowed to use the postnominal title ForMemRS. The Royal Society President is Venkatraman Ramakrishnan, who took up the post on 30 November 2015, since 1967, the society has been based at 6–9 Carlton House Terrace, a Grade I listed building in central London which was previously used by the Embassy of Germany, London. The Royal Society started from groups of physicians and natural philosophers, meeting at variety of locations and they were influenced by the new science, as promoted by Francis Bacon in his New Atlantis, from approximately 1645 onwards. A group known as The Philosophical Society of Oxford was run under a set of rules still retained by the Bodleian Library, after the English Restoration, there were regular meetings at Gresham College. It is widely held that these groups were the inspiration for the foundation of the Royal Society, I will not say, that Mr Oldenburg did rather inspire the French to follow the English, or, at least, did help them, and hinder us. But tis well known who were the men that began and promoted that design. This initial royal favour has continued and, since then, every monarch has been the patron of the society, the societys early meetings included experiments performed first by Hooke and then by Denis Papin, who was appointed in 1684. These experiments varied in their area, and were both important in some cases and trivial in others. The Society returned to Gresham in 1673, there had been an attempt in 1667 to establish a permanent college for the society. Michael Hunter argues that this was influenced by Solomons House in Bacons New Atlantis and, to a lesser extent, by J. V. The first proposal was given by John Evelyn to Robert Boyle in a letter dated 3 September 1659, he suggested a scheme, with apartments for members. The societys ideas were simpler and only included residences for a handful of staff and these plans were progressing by November 1667, but never came to anything, given the lack of contributions from members and the unrealised—perhaps unrealistic—aspirations of the society. During the 18th century, the gusto that had characterised the early years of the society faded, with a number of scientific greats compared to other periods. The pointed lightning conductor had been invented by Benjamin Franklin in 1749, during the same time period, it became customary to appoint society fellows to serve on government committees where science was concerned, something that still continues. The 18th century featured remedies to many of the early problems
16.
Hampton, London
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Hampton is a suburban area on the north bank of the River Thames, in the London Borough of Richmond upon Thames, England, which includes Hampton Court Palace. Hampton is served by two stations, including one immediately south of Hampton Court Bridge in East Molesey. Hampton adjoins Bushy Park on two sides and is west of Hampton Wick and Kingston upon Thames, there are long strips of public riverside in Hampton and the Hampton Heated Open Air Pool is one of the few such swimming pools in Greater London. Hampton Ferry provides access across the Thames to the park of Molesey. The most common type of housing in the north of the district is terraced homes, the combined population of the Hamptons was 37,131 at the 2001 census. The name Hampton may come from the Anglo-Saxon words hamm meaning an enclosure in the bend of a river and ton meaning farmstead or settlement. The ten years to 1911 saw the highest percentage of population increase, a further 25% rise took place in the 1920s. Writing between 1870–72 his national gazetteer, John Marius Wilson technically described Hampton Wick as a hamlet, world War I impacted the business, which rebranded as The Thames Riviera, rivalling the hotel in Maidenhead for the name, followed by The Palm Beach and The Casino. This high precision survey was the forerunner of the Principal Triangulation of Great Britain which commenced in 1791, in the report of the operation Roy gives the locations of the ends of the baseline as Hampton Poor-house and Kings Arbour. The latter lies with the confines of Heathrow Airport and it is certain that the cannons have been disturbed and slightly moved over the intervening years Hampton Academy, an Academy in Hampton Hampton School, an independent school for boys. Lady Eleanor Holles School is an independent school for girls and it is 83rd in the schools league table. The latter two schools achieved 100%5 A*-Cs at GCSE and share a new-for-2000 Millennium Boathouse, Oxford and Cambridge Boat Race and Womens Oxford v Cambridge Henley Boat Race participants of this century have attended the schools. The church buildings are a significant presence in the many of them being architecturally stand-alone listed buildings in otherwise often quite homogenous 20th century housing estates. The ministers and members provide a range of services for the community, Hampton Youth Project has been an economically and recreationally resourceful youth centre since 1990. Built in a coach depot on the Nurserylands Estate it offers a wide programme of activities for those aged 11–19. Hampton Station is on the London Waterloo to Shepperton train line, Thames Waters fresh water operations provide a source of local employment. A group of 17 offices and storage premises including warehouse units, the large operational Water Treatment Works, owned by Thames Water, is between the Upper Sunbury Road and the River Thames. It was built in the 1850s after the 1852 Metropolis Water Act made it illegal to take drinking water from the tidal Thames below Teddington Lock because of the amount of sewage in the river
17.
Hounslow Heath
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Hounslow Heath is a local nature reserve in the London Borough of Hounslow. The public open space, which covers 200 acres, is all that remains of the historic Hounslow Heath which covered more than 4,000 acres. The present day area is bounded by A315 Staines Road, A3063 Wellington Road South, A314 Hanworth Road, Hounslow Heath has had major historical importance, originally crossed by main routes from London to the west and southwest of Britain. Staines Road, the boundary of the present heath, was the Roman Road. There are several references to Roman camps on or close to the heath. Continuous recorded history back to Norman times. In 1546, Hounslow Heath was surveyed with an area of 4,293 acres. Various armies used the heath due to its proximity to London, Windsor, oliver Cromwell stationed an army there at the end of the English Civil War in 1647. James II camped his army there, and conducted military exercises, in 1793, Hounslow Barracks was built to the north of Staines Road as part of the preparations to meet a possible French invasion. In the 17th and 18th centuries, the heath was notorious as the haunt of highwaymen and footpads, being crossed by the Great West Road and the Bath Road. A sighting was made of the spire of All Saints church in Banstead and this work by General William Roy was the start of the Anglo-French Survey, which led to the Principal Triangulation of Great Britain. By 1900, the heath was still in use as a ground for horse-mounted cavalry based at Hounslow Barracks, a gun shooting range. After the outbreak of World War I in 1914, Hounslow Heath Aerodrome was established, in 1919, the aerodrome became the sole London Terminal Aerodrome, and hosted the first scheduled daily international commercial air services. In 1920, it surrendered its role to Croydon Airport, the heath was then again used for military training and a repair depot. A plaque marks the entrance to Londons first civil airport, stating, from here the first British international airline operation and the first flight from Europe to Australia was made. Erected by the Heston and Isleworth Borough Council An area to the west of the present heath was used for gravel extraction after World War II, used for landfill until the late 1960s, the land was reclaimed to form Hounslow Heath Golf Centre which opened in 1979. Bronze Age spearheads, axes, and sword and knife fragments from Hounslow, are held at the British Museum, also Celtic badges and amulets discovered in a field at Hounslow in 1864. In 1999, excavations on the former Feltham Marshalling Yards to the south of the heath unearthed remains of an Iron Age furnace, there are various remains of former mills and other industrial archaeological features adjoining the River Crane near the heath
18.
Theodolite
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A theodolite /θiːˈɒdəlaɪt/ is a precision instrument for measuring angles in the horizontal and vertical planes. Theodolites are used mainly for surveying applications, and have adapted for specialized purposes such as meteorology. A modern theodolite consists of a telescope mounted within two perpendicular axes, the horizontal or trunnion axis and the zenith axis. A theodolite measures vertical angles as angles between the zenith, forwards or plunged—typically approximately 90 and 270 degrees, when the telescope is pointed at a target object, the angle of each of these axes can be measured with great precision, typically to seconds of arc. A theodolite may be either transit or non-transit, in a transit theodolite, the telescope can be inverted in the vertical plane, whereas the rotation in the same plane is restricted to a semi-circle in a non-transit theodolite. Some types of transit theodolites do not allow the measurement of vertical angles, the builders level is sometimes mistaken for a transit theodolite, but it measures neither horizontal nor vertical angles. It uses a level to set a telescope level to define a line of sight along a horizontal plane. A theodolite is mounted on its head by means of a forced centering plate or tribrach containing four thumbscrews, or in modern theodolites. Before use, a theodolite must be placed vertically above the point to be measured using a plumb bob. The instrument is then set level using leveling footscrews and circular, both axes of a theodolite are equipped with graduated circles that can be read through magnifying lenses. The vertical circle which transits about the horizontal axis should read 90° when the axis is horizontal, or 270° when the instrument is in its second position. Half of the difference between the two positions is called the index error, the horizontal and vertical axes of a theodolite must be perpendicular, if not then a horizontal axis error exists. This can be tested by aligning the tubular spirit bubble parallel to a line between two footscrews and setting the bubble central, a horizontal axis error is present if the bubble runs off central when the tubular spirit bubble is reversed. To adjust, the operator removes 1/2 the amount the bubble has run off using the screw, then re-level, test. If not, then a collimation error exists, index error, horizontal axis error and collimation error are regularly determined by calibration and are removed by mechanical adjustment. Their existence is taken account in the choice of measurement procedure in order to eliminate their effect on the measurement results of the theodolite. The term diopter was used in old texts as a synonym for theodolite. This derives from an astronomical instrument called a dioptra
19.
Jesse Ramsden
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Jesse Ramsden FRS FRSE was an English mathematician, astronomical and scientific instrument maker. Ramsden was born at Salterhebble, Halifax, West Riding of Yorkshire, England. Having attended the school at Halifax for three years, he was sent at the age of twelve to his uncle at Craven in the North Riding. After serving his apprenticeship as a cloth-worker in Halifax, he went to London where, in 1755, in 1758 he was apprenticed to a mathematical instrument maker and he proved so proficient that he was able to set up his own business only four years later. The quality and accuracy of his instruments established his reputation as the most able instrument maker in Europe for the forty years until his death in 1800. Ramsden married Sarah Dollond, daughter of John Dollond the famous maker of quality lenses. Little is known of their life together but Sarah did not accompany him when he moved his workshop, in his later years he lived above the workshop with a number of his apprentices. The acrimony sometimes got out of hand, in his favour it should be pointed out that many delays could be attributed to Ramsdens quest for perfection, continually refining his designs as the slightest shortcomings were revealed. He was elected to the Royal Society in 1786 and to the Royal Society of Edinburgh in 1798. The Copley Medal of the Royal Society was bestowed him in 1795 for his various inventions and improvements in philosophical instruments. ’ He died five years later at Brighton. Ramsden created one of the first high-quality dividing engines and this led to his speciality in dividing circles, which began to supersede the quadrants in observatories towards the end of the 18th century. He published a Description of an Engine for dividing Mathematical Instruments in 1777 and this work provided the basis for the subsequent Ordnance Survey of the counties of Britain. Ramsden is also responsible for the achromatic eyepiece named after him, the exit pupil of an eyepiece was once called the Ramsden disc in his honour. In 1791 he completed the Shuckburgh telescope, an equatorial mounted refracting telescope, chisholm, Hugh, ed. Ramsden, Jesse, Encyclopaedia Britannica Eleventh Edition,17, Cambridge University Press. Notes and records of the Royal Society, a review of the book by Anita McConnell, Jesse Ramsden, Londons leading scientific instrument maker. The Tale of the Great Theodolites, FIG Working Week on Integrating the Generations. Kern, Ralf, Wissenschaftliche Instrumente in ihrer Zeit, Account of the life and labours of the late Mr. Ramsden. Letter of Professor Giuseppe Piazzi to M. de Lalande, the Mirror of Literature, Amusement and Instruction
20.
Ramsden surveying instruments
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The Ramsden surveying instruments discussed in this article are those constructed by Jesse Ramsden and used in high precision geodetic surveys carried out in the period 1784 to 1853. This includes the five great theodolites—great in name, great in size and great in accuracy—used in surveys of Britain, Ramsden also provided the equipment used in the measurement of the many base lines of these surveys and also the zenith telescope used in latitude determinations. A total of eight such instruments were manufactured by Ramsden and others for use in Britain, India, Ramsden himself constructed three theodolites and a further two were completed to his design by Mathew Berge, his son-in-law and business successor, after Ramsdens death in 1805. Of the other one was constructed by William Cary and the other two by the firm of Troughton and Simms. Approval having been granted, General William Roy agreed to undertake the work, there is a complete description of this theodolite in the final report of the Anglo-French Survey. The instrument was large,36 inches across and it was mounted on a stand which placed the sighting telescope between 5 and 6 ft. high. It weighed about 200 lb and the accessories and cases weighed as much again and it travelled around Britain for over sixty years, in its own sprung carriage, to locations where it was hauled up mountains, church towers and even scaffolded steeples. The instrument is also fitted with a vertical semi-circular scale to measure the elevations of distant stations, cross wires similar to those used in the microscopes are fitted into the eyepiece, they are adjustable by a screw thread which allowed angles to be measured to within five arc seconds. No other theodolite could match this precision at that time and it was the first instrument to be able to measure the spherical excess of large survey triangles. After completion of the Anglo-French survey this instrument was stored at the Royal Society, on completion of the Survey the theodolite was stored in the headquarters of the Ordnance Survey at Southampton where it was destroyed in the bomb raids of 1941. In his report to the Royal Society in 1775 William Roy had noted the suitability of India as a location for both meridian arc and parallel arc measurements, to his delight the East India Company were willing to undertake such a venture and ordered a second great theodolite from Ramsden. It was ready in 1791 but Ramsden felt obliged to increase the price because of problems in its manufacture, to his surprise the company rejected his price and refused to purchase the instrument. It was bought by the Duke of Richmond who, as Master of the Board of Ordnance, had provided most of the finance for Roys Anglo-French Survey, the theodolite is designated as the Board of Ordnance theodolite, or Ramsden BO in short. Richmonds intention was to use the new theodolite on the extension of Roys survey to the counties of Britain. The instrument was basically the same as the first with added refinements, mainly to the number and it was in use until the completion of the Principal Triangulation of Great Britain in 1853 and it is now in the Science Museum in London. There is a description of the made to this theodolite in the account of the Trigonometrical Survey for the years 1791–1794 by Mudge, Williams. Ramsden made at least one other 3ft, theodolite of which parts were discovered in Switzerland. After his death his firm was inherited by Mathew Berge who is known to have constructed two more instruments to Ramsdens design
21.
Minute and second of arc
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A minute of arc, arcminute, arc minute, or minute arc is a unit of angular measurement equal to 1/60 of one degree. Since one degree is 1/360 of a turn, one minute of arc is 1/21600 of a turn, a second of arc, arcsecond, or arc second is 1/60 of an arcminute, 1/3600 of a degree, 1/1296000 of a turn, and π/648000 of a radian. To express even smaller angles, standard SI prefixes can be employed, the number of square arcminutes in a complete sphere is 4 π2 =466560000 π ≈148510660 square arcminutes. The standard symbol for marking the arcminute is the prime, though a single quote is used where only ASCII characters are permitted. One arcminute is thus written 1′ and it is also abbreviated as arcmin or amin or, less commonly, the prime with a circumflex over it. The standard symbol for the arcsecond is the prime, though a double quote is commonly used where only ASCII characters are permitted. One arcsecond is thus written 1″ and it is also abbreviated as arcsec or asec. In celestial navigation, seconds of arc are used in calculations. This notation has been carried over into marine GPS receivers, which normally display latitude and longitude in the format by default. An arcsecond is approximately the angle subtended by a U. S. dime coin at a distance of 4 kilometres, a milliarcsecond is about the size of a dime atop the Eiffel Tower as seen from New York City. A microarcsecond is about the size of a period at the end of a sentence in the Apollo mission manuals left on the Moon as seen from Earth, since antiquity the arcminute and arcsecond have been used in astronomy. The principal exception is Right ascension in equatorial coordinates, which is measured in units of hours, minutes. These small angles may also be written in milliarcseconds, or thousandths of an arcsecond, the unit of distance, the parsec, named from the parallax of one arcsecond, was developed for such parallax measurements. It is the distance at which the radius of the Earths orbit would subtend an angle of one arcsecond. The ESA astrometric space probe Gaia is hoped to measure star positions to 20 microarcseconds when it begins producing catalog positions sometime after 2016, there are about 1.3 trillion µas in a turn. Currently the best catalog positions of stars actually measured are in terms of milliarcseconds, apart from the Sun, the star with the largest angular diameter from Earth is R Doradus, a red supergiant with a diameter of 0.05 arcsecond. The dwarf planet Pluto has proven difficult to resolve because its angular diameter is about 0.1 arcsecond, space telescopes are not affected by the Earths atmosphere but are diffraction limited. For example, the Hubble space telescope can reach a size of stars down to about 0. 1″
22.
Spherical trigonometry
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Spherical trigonometry is of great importance for calculations in astronomy, geodesy and navigation. The origins of spherical trigonometry in Greek mathematics and the developments in Islamic mathematics are discussed fully in History of trigonometry. This book is now available on the web. The only significant developments since then have been the application of methods for the derivation of the theorems. A spherical polygon is a polygon on the surface of the sphere defined by a number of great-circle arcs, such polygons may have any number of sides. Two planes define a lune, also called a digon or bi-angle, the analogue of the triangle. Three planes define a triangle, the principal subject of this article. Four planes define a spherical quadrilateral, such a figure, and higher sided polygons, from this point the article will be restricted to spherical triangles, denoted simply as triangles. Both vertices and angles at the vertices are denoted by the upper case letters A, B and C. The angles of spherical triangles are less than π so that π < A + B + C < 3π. The sides are denoted by letters a, b, c. On the unit sphere their lengths are equal to the radian measure of the angles that the great circle arcs subtend at the centre. The sides of proper spherical triangles are less than π so that 0 < a + b + c < 3π, the radius of the sphere is taken as unity. For specific practical problems on a sphere of radius R the measured lengths of the sides must be divided by R before using the identities given below, likewise, after a calculation on the unit sphere the sides a, b, c must be multiplied by R. The polar triangle associated with a triangle ABC is defined as follows, consider the great circle that contains the side BC. This great circle is defined by the intersection of a plane with the surface. The points B and C are defined similarly, the triangle ABC is the polar triangle corresponding to triangle ABC. Therefore, if any identity is proved for the triangle ABC then we can derive a second identity by applying the first identity to the polar triangle by making the above substitutions
23.
Science Museum, London
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The Science Museum is a major museum on Exhibition Road in South Kensington, London. It was founded in 1857 and today is one of the major tourist attractions. Like other publicly funded museums in the United Kingdom, the Science Museum does not charge visitors for admission. Temporary exhibitions, however, may incur an admission fee and it is part of the Science Museum Group, having merged with the Museum of Science and Industry in Manchester in 2012. It included a collection of machinery which became the Museum of Patents in 1858, and this collection contained many of the most famous exhibits of what is now the Science Museum. In 1883, the contents of the Patent Office Museum were transferred to the South Kensington Museum, in 1885, the Science Collections were renamed the Science Museum and in 1893 a separate director was appointed. The Art Collections were renamed the Art Museum, which became the Victoria. When Queen Victoria laid the stone for the new building for the Art Museum, she stipulated that the museum be renamed after herself. On 26 June 1909 the Science Museum, as an independent entity, the Science Museums present quarters, designed by Sir Richard Allison, were opened to the public in stages over the period 1919–28. This building was known as the East Block, construction of which began in 1913, as the name suggests it was intended to be the first building of a much larger project, which was never realized. It also contains hundreds of interactive exhibits, a recent addition is the IMAX 3D Cinema showing science and nature documentaries, most of them in 3-D, and the Wellcome Wing which focuses on digital technology. Entrance has been free since 1 December 2001, the museum houses some of the many objects collected by Henry Wellcome around a medical theme. The fourth floor exhibit is called Glimpses of Medical History, with reconstructions, the fifth floor gallery is called Science and the Art of Medicine, with exhibits of medical instruments and practices from ancient days and from many countries. The collection is strong in clinical medicine, biosciences and public health, the museum is a member of the London Museums of Health & Medicine. The Science Museum has a library, and until the 1960s was Britains National Library for Science, Medicine. It holds runs of periodicals, early books and manuscripts, and is used by scholars worldwide and it was, for a number of years, run in conjunction with the Library of Imperial College, but in 2007 the Library was divided over two sites. The Imperial College library catalogue search system now informs searchers that volumes formerly held there are Available at Science Museum Library Swindon Currently unavailable, a new Research Centre with library facilities is promised for late 2015 but is unlikely to have book stacks nearby. The Science Museums medical collections have a scope and coverage
24.
East India Company
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The company also ruled the beginnings of the British Empire in India. The company received a Royal Charter from Queen Elizabeth I on 31 December 1600, wealthy merchants and aristocrats owned the Companys shares. Initially the government owned no shares and had only indirect control, during its first century of operation the focus of the Company was trade, not the building of an empire in India. The company eventually came to rule large areas of India with its own armies, exercising military power. Despite frequent government intervention, the company had recurring problems with its finances, the official government machinery of British India had assumed its governmental functions and absorbed its armies. Soon after the defeat of the Spanish Armada in 1588, London merchants presented a petition to Queen Elizabeth I for permission to sail to the Indian Ocean, one of them, Edward Bonventure, then sailed around Cape Comorin to the Malay Peninsula and returned to England in 1594. In 1596, three ships sailed east, however, these were all lost at sea. Two days later, on 24 September, the Adventurers reconvened and resolved to apply to the Queen for support of the project, the Adventurers convened again a year later. For a period of fifteen years the charter awarded the newly formed company a monopoly on trade with all countries east of the Cape of Good Hope and west of the Straits of Magellan. Anybody who traded in breach of the charter without a licence from the Company was liable to forfeiture of their ships and cargo, the governance of the company was in the hands of one governor and 24 directors or committees, who made up the Court of Directors. They, in turn, reported to the Court of Proprietors, ten committees reported to the Court of Directors. According to tradition, business was transacted at the Nags Head Inn, opposite St Botolphs church in Bishopsgate. Sir James Lancaster commanded the first East India Company voyage in 1601, in March 1604 Sir Henry Middleton commanded the second voyage. Early in 1608 Alexander Sharpeigh was appointed captain of the Companys Ascension, thereafter two ships, Ascension and Union sailed from Woolwich on 14 March 1607–8. Initially, the company struggled in the trade because of the competition from the already well-established Dutch East India Company. The company opened a factory in Bantam on the first voyage, the factory in Bantam was closed in 1683. During this time belonging to the company arriving in India docked at Surat. In the next two years, the company established its first factory in south India in the town of Machilipatnam on the Coromandel Coast of the Bay of Bengal
25.
Ordnance Survey
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Ordnance Survey is a non-ministerial government department which acts as the national mapping agency for Great Britain and is one of the worlds largest producers of maps. Since 1 April 2015 it has operated as Ordnance Survey Ltd, the Ordnance Survey Board remain accountable to the Secretary of State for Business, Energy and Industrial Strategy. It is also a member of the Public Data Group, the agencys name indicates its original military purpose, mapping Scotland in the wake of the Jacobite rebellion in 1745. There was also a general and nationwide need in light of the potential threat of invasion during the Napoleonic Wars. Ordnance Survey mapping is usually classified as either large-scale or small-scale, the Surveys large-scale mapping comprises maps at six inches to the mile or more and was available as sheets until the 1980s, when it was digitised. Small-scale mapping comprises maps at less than six inches to the mile, such as the one inch to the mile leisure maps. These are still available in sheet form. Ordnance Survey maps remain in copyright for fifty years after their publication, some of the Copyright Libraries hold complete or near-complete collections of pre-digital OS mapping. The origins of the Ordnance Survey lie in the aftermath of the last Jacobite rising which was defeated by forces loyal to the government at the Battle of Culloden in 1746. In 1747, Lieutenant-colonel David Watson proposed the compilation of a map of the Highlands to facilitate the subjugation of clans, in response, King George II charged Watson with making a military survey of the Highlands under the command of the Duke of Cumberland. Among Watsons assistants were William Roy, Paul Sandby and John Manson, the survey was produced at a scale of 1 inch to 1000 yards and included the Duke of Cumberlands Map now held in the British Library. This work was the point of the Principal Triangulation of Great Britain. Roys technical skills and leadership set the standard for which Ordnance Survey became known. Work was begun in earnest in 1790 under Roys supervision, when the Board of Ordnance began a military survey starting with the south coast of England. A set of stamps, featuring maps of the Kentish village of Hamstreet, was issued in 1991 to mark the bicentenary. In 1801, the first one-inch-to-the-mile map was published, detailing the county of Kent, during the next twenty years, roughly a third of England and Wales was mapped at the same scale under the direction of William Mudge, as other military matters took precedence. It took until 1823 to re-establish a relationship with the French survey made by Roy in 1787, by 1810, one inch to the mile maps of most of the south of England were completed, but were withdrawn from sale between 1811 and 1816 because of security fears. It was gruelling work, major Thomas Colby, later the longest serving director general of Ordnance Survey, in 1824, Colby and most of his staff moved to Ireland to work on a six-inches-to-the-mile valuation survey
26.
Spherical geometry
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Spherical geometry is the geometry of the two-dimensional surface of a sphere. It is an example of a geometry that is not Euclidean, two practical applications of the principles of spherical geometry are navigation and astronomy. In plane geometry, the concepts are points and lines. On a sphere, points are defined in the usual sense, the equivalents of lines are not defined in the usual sense of straight line in Euclidean geometry, but in the sense of the shortest paths between points, which are called geodesics. On a sphere, the geodesics are the circles, other geometric concepts are defined as in plane geometry. Spherical geometry is not elliptic geometry, but is rather a subset of elliptic geometry, for example, it shares with that geometry the property that a line has no parallels through a given point. An important geometry related to that of the sphere is that of the projective plane. Locally, the plane has all the properties of spherical geometry. In particular, it is non-orientable, or one-sided, Concepts of spherical geometry may also be applied to the oblong sphere, though minor modifications must be implemented on certain formulas. Higher-dimensional spherical geometries exist, see elliptic geometry, the earliest mathematical work of antiquity to come down to our time is On the rotating sphere by Autolycus of Pitane, who lived at the end of the fourth century BC. The book of unknown arcs of a written by the Islamic mathematician Al-Jayyani is considered to be the first treatise on spherical trigonometry. The book contains formulae for right-handed triangles, the law of sines. The book On Triangles by Regiomontanus, written around 1463, is the first pure trigonometrical work in Europe, however, Gerolamo Cardano noted a century later that much of its material on spherical trigonometry was taken from the twelfth-century work of the Andalusi scholar Jabir ibn Aflah. L. Euler, De curva rectificabili in superficie sphaerica, Novi Commentarii academiae scientiarum Petropolitanae 15,1771, pp. 195–216, Opera Omnia, Series 1, Volume 28, pp. 142–160. L. Euler, De mensura angulorum solidorum, Acta academiae scientarum imperialis Petropolitinae 2,1781, p. 31–54, Opera Omnia, Series 1, vol. L. Euler, Problematis cuiusdam Pappi Alexandrini constructio, Acta academiae scientarum imperialis Petropolitinae 4,1783, p. 91–96, Opera Omnia, Series 1, vol. L. Euler, Geometrica et sphaerica quaedam, Mémoires de lAcademie des Sciences de Saint-Petersbourg 5,1815, p. 96–114, Opera Omnia, Series 1, vol. L. Euler, Trigonometria sphaerica universa, ex primis principiis breviter et dilucide derivata, Acta academiae scientarum imperialis Petropolitinae 3,1782, p. 72–86, Opera Omnia, Series 1, vol
27.
Ordnance Survey Drawings
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The British Library holds 351 of the original preliminary drawings made by the surveyors between the 1780s and 1840. They cover most of England south of a line between Liverpool and Hull and these drawings were produced as the base for the production of a one inch map for the country. Nowadays, OSD are value for genealogists for their place-names and by historians for their depiction of the expanding canal. They are seen as a record of land use in the eighteenth. They can be seen at the Online Gallery at The British Library web page
28.
Great Trigonometrical Survey
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The Great Trigonometrical Survey was a project which aimed to measure the entire Indian subcontinent with scientific precision. It was begun in 1802 by the infantry officer William Lambton, under the leadership of his successor, George Everest, the project was made a responsibility of the Survey of India. Everest was succeeded by Andrew Scott Waugh and after 1861 the project was led by James Walker, among the many accomplishments of the Survey were the demarcation of the British territories in India and the measurement of the height of the Himalayan giants, Everest, K2, and Kanchenjunga. From its inception in 1600 to the beginning of the nineteenth century, with the acquisition of new territory, it employed several explorers and cartographers to provide maps and other information on its territories, most notably James Rennell, from 1767 in Bengal. As Rennell proceeded making maps, some flaws in them surfaced, based on a lack of precise measurements. The Great Trigonometrical Survey of India started on 10 April 1802 with the measurement of a baseline near Madras, major Lambton selected the flat plains with St. Thomas Mount at the north end and Perumbauk hill at the southern end. The baseline was 7.5 miles long, lieutenant Kater was despatched to find high vantage points on the hills of the west so that the coastal points of Tellicherry and Cannanore could be connected. The high hills chosen were Mount Delly and Tadiandamol, the distance from coast to coast was 360 miles and this survey line was completed in 1806. The East India Company thought that this project would take about 5 years but eventually it took nearly 70 years well past the Indian Rebellion of 1857, at times the survey party numbered 700 people. The Trigonometrical Survey was conducted independent of other surveys, notably the topographical, in 1875 the decision was taken that the Survey budget should be reduced from 240,000 to 200,000 pounds. This resulted in a reorganization under Surveyor-General Colonel J. T. Walker to amalgamate the Great Trigonometrical, Topographical, triangulation surveys were based on a few carefully measured baselines and a series of angles. The initial baseline was measured with accuracy, since the accuracy of the subsequent survey was critically dependent upon it. Various corrections were applied, principally temperature, an especially accurate folding chain was used, laid on horizontal tables, all shaded from the sun and with a constant tension. The early surveys made use of large and bulky theodolites made by William Carey, later surveys used more compact theodolites. Accurate instruments could not always be purchased through the system of government contract. He had a maker, Henry Barrow, set up an instrument company in Calcutta, for a while Barrow was succeeded by Syed Mohsin from Arcot and after his death the instruments were supplied by Cooke from York. The Great Trigonometrical Survey of India in a Historical Perspective by Rama Deb Roy
29.
International Standard Book Number
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The International Standard Book Number is a unique numeric commercial book identifier. An ISBN is assigned to each edition and variation of a book, for example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, the method of assigning an ISBN is nation-based and varies from country to country, often depending on how large the publishing industry is within a country. The initial ISBN configuration of recognition was generated in 1967 based upon the 9-digit Standard Book Numbering created in 1966, the 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108. Occasionally, a book may appear without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure, however, this can be rectified later. Another identifier, the International Standard Serial Number, identifies periodical publications such as magazines, the ISBN configuration of recognition was generated in 1967 in the United Kingdom by David Whitaker and in 1968 in the US by Emery Koltay. The 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108, the United Kingdom continued to use the 9-digit SBN code until 1974. The ISO on-line facility only refers back to 1978, an SBN may be converted to an ISBN by prefixing the digit 0. For example, the edition of Mr. J. G. Reeder Returns, published by Hodder in 1965, has SBN340013818 -340 indicating the publisher,01381 their serial number. This can be converted to ISBN 0-340-01381-8, the check digit does not need to be re-calculated, since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with Bookland European Article Number EAN-13s. An ISBN is assigned to each edition and variation of a book, for example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, a 13-digit ISBN can be separated into its parts, and when this is done it is customary to separate the parts with hyphens or spaces. Separating the parts of a 10-digit ISBN is also done with either hyphens or spaces, figuring out how to correctly separate a given ISBN number is complicated, because most of the parts do not use a fixed number of digits. ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency that is responsible for country or territory regardless of the publication language. Some ISBN registration agencies are based in national libraries or within ministries of culture, in other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded. In Canada, ISBNs are issued at no cost with the purpose of encouraging Canadian culture. In the United Kingdom, United States, and some countries, where the service is provided by non-government-funded organisations. Australia, ISBNs are issued by the library services agency Thorpe-Bowker
30.
Henry James (British Army officer)
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Major General Sir Henry James FRS MRIA RE was the director-general of the Ordnance Survey, the British Government mapping agency, from 1854 to 1875. Sir Henry was described by the agency itself as perhaps Ordnance Surveys most eccentric, Sir Henry spent most of his life working for the Ordnance Survey and after becoming its head he introduced the new science of photography. He also would later claim to be the inventor of the known as Photozincography or Zinco. Sir Henry also played a part in the resolving of the battle of the scales, born in 1803 at Rose Vale near St Agnes, Cornwall, he was the fifth son of John James of Truro and Jane, daughter of John Hoskers. He attended a school in Exeter, going on to study at the Royal Military Academy, Woolwich. He was promoted to captain in 1846 and then to Colonel in 1857 and his appointment to become head of the Ordnance Survey was controversial as his father-in-law Major-General Edward Watson RE aided him above two more obvious candidates. He married Anne, the daughter of Major General Watson, Royal Engineers, in 1854, at the age of 51, he became Superintendent of the Ordnance Survey, taking over from Lieutenant Colonel Lewis Hall. He was far more experienced than his predecessor having worked most of his life for the Survey, upon assuming the directorship, Sir Henry became involved in the battle of the scales. While the Ordnance Survey had surveyed a large part of the country, Sir Henry was a firm believer in the 1.2500 scale, and he used his position to effect this change despite the less than full approval of his superiors. James created a department to the Ordnance Survey in 1855 as a means of reducing the scale of maps. He claimed to have invented photozincography, a method of producing printing plates. In fact, the process had developed by two of his staff. However James was the force behind using the process to create. Sir Henry has been called, by T. Owen, one of the greatest image builders the Ordnance Survey ever had, because Sir Henry made all the advances he, Sir Henry James continued using his photozincographic process to preserve historic manuscripts. He went on to publish a series of English historical documents. Similarly he ordered the surveying of Jerusalem which was commissioned to improve the water supply to the city. A copy of this map still survives at the National Archives, due to failing health Sir Henry retired in 1875 at the age of 72, having been Director General of the Ordnance Survey for 21 years. His retirement was welcomed by his colleagues and soon after his departure a thinly veiled attack on his running of the survey was released in the Hampshire Independent in 1875, Sir Henry James died on 14 June 1877, at the age of 75, at his home in Southampton
31.
OCLC
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The Online Computer Library Center is a US-based nonprofit cooperative organization dedicated to the public purposes of furthering access to the worlds information and reducing information costs. It was founded in 1967 as the Ohio College Library Center, OCLC and its member libraries cooperatively produce and maintain WorldCat, the largest online public access catalog in the world. OCLC is funded mainly by the fees that libraries have to pay for its services, the group first met on July 5,1967 on the campus of the Ohio State University to sign the articles of incorporation for the nonprofit organization. The group hired Frederick G. Kilgour, a former Yale University medical school librarian, Kilgour wished to merge the latest information storage and retrieval system of the time, the computer, with the oldest, the library. The goal of network and database was to bring libraries together to cooperatively keep track of the worlds information in order to best serve researchers and scholars. The first library to do online cataloging through OCLC was the Alden Library at Ohio University on August 26,1971 and this was the first occurrence of online cataloging by any library worldwide. Membership in OCLC is based on use of services and contribution of data, between 1967 and 1977, OCLC membership was limited to institutions in Ohio, but in 1978, a new governance structure was established that allowed institutions from other states to join. In 2002, the structure was again modified to accommodate participation from outside the United States. As OCLC expanded services in the United States outside of Ohio, it relied on establishing strategic partnerships with networks, organizations that provided training, support, by 2008, there were 15 independent United States regional service providers. OCLC networks played a key role in OCLC governance, with networks electing delegates to serve on OCLC Members Council, in early 2009, OCLC negotiated new contracts with the former networks and opened a centralized support center. OCLC provides bibliographic, abstract and full-text information to anyone, OCLC and its member libraries cooperatively produce and maintain WorldCat—the OCLC Online Union Catalog, the largest online public access catalog in the world. WorldCat has holding records from public and private libraries worldwide. org, in October 2005, the OCLC technical staff began a wiki project, WikiD, allowing readers to add commentary and structured-field information associated with any WorldCat record. The Online Computer Library Center acquired the trademark and copyrights associated with the Dewey Decimal Classification System when it bought Forest Press in 1988, a browser for books with their Dewey Decimal Classifications was available until July 2013, it was replaced by the Classify Service. S. The reference management service QuestionPoint provides libraries with tools to communicate with users and this around-the-clock reference service is provided by a cooperative of participating global libraries. OCLC has produced cards for members since 1971 with its shared online catalog. OCLC commercially sells software, e. g. CONTENTdm for managing digital collections, OCLC has been conducting research for the library community for more than 30 years. In accordance with its mission, OCLC makes its research outcomes known through various publications and these publications, including journal articles, reports, newsletters, and presentations, are available through the organizations website. The most recent publications are displayed first, and all archived resources, membership Reports – A number of significant reports on topics ranging from virtual reference in libraries to perceptions about library funding
32.
Triangulation
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In trigonometry and geometry, triangulation is the process of determining the location of a point by forming triangles to it from known points. Optical 3D measuring systems use this principle as well in order to determine the spatial dimensions, basically, the configuration consists of two sensors observing the item. One of the sensors is typically a digital device. The projection centers of the sensors and the point on the object’s surface define a triangle. Within this triangle, the distance between the sensors is the base b and must be known, by determining the angles between the projection rays of the sensors and the basis, the intersection point, and thus the 3D coordinate, is calculated from the triangular relations. Triangulation today is used for many purposes, including surveying, navigation, metrology, astrometry, binocular vision, model rocketry, the use of triangles to estimate distances dates to antiquity. He measured the length of the shadows and that of his own at the same moment. Such techniques would have been familiar to the ancient Egyptians. Problem 57 of the Rhind papyrus, a thousand years earlier, defines the seqt or seked as the ratio of the run to the rise of a slope, i. e. the reciprocal of gradients as measured today. The slopes and angles were measured using a rod that the Greeks called a dioptra
33.
Atlas
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An atlas is a collection of maps, it is typically a map of Earth or a region of Earth, but there are atlases of the other planets in the Solar System. Furthermore, atlases of anatomy exist, mapping out the body or other organisms. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats, in addition to presenting geographic features and political boundaries, many atlases often feature geopolitical, social, religious and economic statistics. They also have information about the map and places in it, the use of the word atlas in a geographical context dates from 1595 when the geographer Gerardus Mercator published Atlas Sive Cosmographicae Meditationes de Fabrica Mundi et Fabricati Figura. This title provides Mercators definition of the word as a description of the creation and form of the whole universe, nonetheless, this distinction is conventionally awarded to the Flemish cartographer Abraham Ortelius who in 1570 published the collection of maps Theatrum Orbis Terrarum. A travel atlas is made for use during travel. It has maps at a large zoom so the maps can be reviewed easily, a travel atlas may also be referred to as a road map. A desk atlas is made similar to a reference book and it may be in hardback or paperback form. With the coming of the market, publishers in different countries can reprint maps from places made elsewhere. This means that the names on the maps often use the designations or abbreviations of the language of the country in which the feature is located. For example, islands near Russia have the abbreviation O. for ostrov and this practice differs from what is standard for any given language, and it reaches its extremity concerning transliterations from other languages. In particular, German mapmakers use the transliterations from Cyrillic developed by the Czechs, national Geographic MapMachine History of atlases Atlases, at the US Library of Congress site - a discussion of many significant atlases, with some illustrations. Part of Geography and Maps, an Illustrated Guide, Historical atlases online Centennia Historical Atlas required reading at the US Naval Academy for over a decade. Manuscript Atlases held by the University of Pennsylvania Libraries - fully digitized with descriptions, Historical Altas in Persuasive Cartography, The PJ Mode Collection, Cornell University Library Other links Google Earth, a visual 3D interactive atlas. Wikimapia a wikiproject designed to describe the entire world
34.
Cartography
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Cartography is the study and practice of making maps. Combining science, aesthetics, and technique, cartography builds on the premise that reality can be modeled in ways that communicate spatial information effectively, the fundamental problems of traditional cartography are to, Set the maps agenda and select traits of the object to be mapped. This is the concern of map editing, traits may be physical, such as roads or land masses, or may be abstract, such as toponyms or political boundaries. Represent the terrain of the object on flat media. This is the concern of map projections, eliminate characteristics of the mapped object that are not relevant to the maps purpose. This is the concern of generalization, reduce the complexity of the characteristics that will be mapped. This is also the concern of generalization, orchestrate the elements of the map to best convey its message to its audience. This is the concern of map design, modern cartography constitutes many theoretical and practical foundations of geographic information systems. The earliest known map is a matter of debate, both because the term map isnt well-defined and because some artifacts that might be maps might actually be something else. A wall painting that might depict the ancient Anatolian city of Çatalhöyük has been dated to the late 7th millennium BCE, the oldest surviving world maps are from 9th century BCE Babylonia. One shows Babylon on the Euphrates, surrounded by Assyria, Urartu and several cities, all, in turn, another depicts Babylon as being north of the world center. The ancient Greeks and Romans created maps since Anaximander in the 6th century BCE, in the 2nd century AD, Ptolemy wrote his treatise on cartography, Geographia. This contained Ptolemys world map – the world known to Western society. As early as the 8th century, Arab scholars were translating the works of the Greek geographers into Arabic, in ancient China, geographical literature dates to the 5th century BCE. The oldest extant Chinese maps come from the State of Qin, dated back to the 4th century BCE, in the book of the Xin Yi Xiang Fa Yao, published in 1092 by the Chinese scientist Su Song, a star map on the equidistant cylindrical projection. Early forms of cartography of India included depictions of the pole star and these charts may have been used for navigation. Mappa mundi are the Medieval European maps of the world, approximately 1,100 mappae mundi are known to have survived from the Middle Ages. Of these, some 900 are found illustrating manuscripts and the remainder exist as stand-alone documents, the Arab geographer Muhammad al-Idrisi produced his medieval atlas Tabula Rogeriana in 1154
35.
Geography
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Geography is a field of science devoted to the study of the lands, the features, the inhabitants, and the phenomena of Earth. The first person to use the word γεωγραφία was Eratosthenes, Geography is an all-encompassing discipline that seeks an understanding of the Earth and its human and natural complexities—not merely where objects are, but how they have changed and come to be. It is often defined in terms of the two branches of geography and physical geography. Geography has been called the world discipline and the bridge between the human and the physical sciences, Geography is a systematic study of the Earth and its features. Traditionally, geography has been associated with cartography and place names, although many geographers are trained in toponymy and cartology, this is not their main preoccupation. Geographers study the space and the temporal database distribution of phenomena, processes, because space and place affect a variety of topics, such as economics, health, climate, plants and animals, geography is highly interdisciplinary. The interdisciplinary nature of the approach depends on an attentiveness to the relationship between physical and human phenomena and its spatial patterns. Names of places. are not geography. know by heart a whole gazetteer full of them would not, in itself and this is a description of the world—that is Geography. In a word Geography is a Science—a thing not of mere names but of argument and reason, of cause, just as all phenomena exist in time and thus have a history, they also exist in space and have a geography. Geography as a discipline can be split broadly into two main fields, human geography and physical geography. The former largely focuses on the environment and how humans create, view, manage. The latter examines the environment, and how organisms, climate, soil, water. The difference between these led to a third field, environmental geography, which combines physical and human geography. Physical geography focuses on geography as an Earth science and it aims to understand the physical problems and the issues of lithosphere, hydrosphere, atmosphere, pedosphere, and global flora and fauna patterns. Physical geography can be divided into broad categories, including, Human geography is a branch of geography that focuses on the study of patterns. It encompasses the human, political, cultural, social, and it requires an understanding of the traditional aspects of physical and human geography, as well as the ways that human societies conceptualize the environment. Integrated geography has emerged as a bridge between the human and the geography, as a result of the increasing specialisation of the two sub-fields. Examples of areas of research in the environmental geography include, emergency management, environmental management, sustainability, geomatics is concerned with the application of computers to the traditional spatial techniques used in cartography and topography
36.
Map
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A map is a symbolic depiction emphasizing relationships between elements of some space, such as objects, regions, or themes. Many maps are static, fixed to paper or some other durable medium, although the earliest maps known are of the heavens, geographic maps of territory have a very long tradition and exist from ancient times. The word map comes from the medieval Latin Mappa mundi, wherein mappa meant napkin or cloth, thus, map became the shortened term referring to a two-dimensional representation of the surface of the world. Cartography or map-making is the study and practice of crafting representations of the Earth upon a flat surface, in addition to location information maps may also be used to portray contour lines indicating constant values of elevation, temperature, rainfall, etc. The orientation of a map is the relationship between the directions on the map and the compass directions in reality. The word orient is derived from Latin oriens, meaning East, in the Middle Ages many maps, including the T and O maps, were drawn with East at the top. Today, the most common – but far from universal – cartographic convention is that North is at the top of a map, several kinds of maps are often traditionally not oriented with North at the top, Maps from non-Western traditions are oriented a variety of ways. Old maps of Edo show the Japanese imperial palace as the top, labels on the map are oriented in such a way that you cannot read them properly unless you put the imperial palace above your head. Medieval European T and O maps such as the Hereford Mappa Mundi were centred on Jerusalem with East at the top, indeed, prior to the reintroduction of Ptolemys Geography to Europe around 1400, there was no single convention in the West. Portolan charts, for example, are oriented to the shores they describe, Maps of cities bordering a sea are often conventionally oriented with the sea at the top. Route and channel maps have traditionally been oriented to the road or waterway they describe, polar maps of the Arctic or Antarctic regions are conventionally centred on the pole, the direction North would be towards or away from the centre of the map, respectively. Typical maps of the Arctic have 0° meridian towards the bottom of the page, reversed maps, also known as Upside-Down maps or South-Up maps, reverse the North is up convention and have south at the top. Buckminster Fullers Dymaxion maps are based on a projection of the Earths sphere onto an icosahedron, the resulting triangular pieces may be arranged in any order or orientation. Modern digital GIS maps such as ArcMap typically project north at the top of the map, compass decimal degrees can be converted to math degrees by subtracting them from 450, if the answer is greater than 360, subtract 360. The scale statement may be taken as exact when the region mapped is small enough for the curvature of the Earth to be neglected, over larger regions where the curvature cannot be ignored we must use map projections from the curved surface of the Earth to the plane. Thus for map projections we must introduce the concept of point scale, which is a function of position, although the scale statement is nominal it is usually accurate enough for all but the most precise of measurements. Large scale maps, say 1,10,000, cover relatively small regions in detail and small scale maps, say 1,10,000,000, cover large regions such as nations, continents. The large/small terminology arose from the practice of writing scales as numerical fractions, there is no exact dividing line between large and small but 1/100,000 might well be considered as a medium scale
37.
Map projection
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A map projection is a systematic transformation of the latitudes and longitudes of locations on the surface of a sphere or an ellipsoid into locations on a plane. Map projections are necessary for creating maps, all map projections distort the surface in some fashion. There is no limit to the number of map projections. More generally, the surfaces of bodies can be mapped even if they are too irregular to be modeled well with a sphere or ellipsoid. Even more generally, projections are the subject of several mathematical fields, including differential geometry. However, map projection refers specifically to a cartographic projection and these useful traits of maps motivate the development of map projections. However, Carl Friedrich Gausss Theorema Egregium proved that a spheres surface cannot be represented on a plane without distortion, the same applies to other reference surfaces used as models for the Earth. Since any map projection is a representation of one of surfaces on a plane. Every distinct map projection distorts in a distinct way, the study of map projections is the characterization of these distortions. Projection is not limited to perspective projections, such as those resulting from casting a shadow on a screen, rather, any mathematical function transforming coordinates from the curved surface to the plane is a projection. Few projections in actual use are perspective, for simplicity, most of this article assumes that the surface to be mapped is that of a sphere. In reality, the Earth and other celestial bodies are generally better modeled as oblate spheroids. These other surfaces can be mapped as well, therefore, more generally, a map projection is any method of flattening a continuous curved surface onto a plane. Many properties can be measured on the Earths surface independent of its geography, some of these properties are, Area Shape Direction Bearing Distance Scale Map projections can be constructed to preserve at least one of these properties, though only in a limited way for most. Each projection preserves or compromises or approximates basic metric properties in different ways, the purpose of the map determines which projection should form the base for the map. Because many purposes exist for maps, a diversity of projections have been created to suit those purposes, another consideration in the configuration of a projection is its compatibility with data sets to be used on the map. Data sets are geographic information, their collection depends on the datum of the Earth. Different datums assign slightly different coordinates to the location, so in large scale maps, such as those from national mapping systems
38.
Topography
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Topography is the study of the shape and features of the surface of the Earth and other observable astronomical objects including planets, moons, and asteroids. The topography of an area could refer to the shapes and features themselves. This field of geoscience and planetary science is concerned with detail in general, including not only relief but also natural and artificial features. This meaning is common in the United States, where topographic maps with elevation contours have made topography synonymous with relief. The older sense of topography as the study of place still has currency in Europe, topography in a narrow sense involves the recording of relief or terrain, the three-dimensional quality of the surface, and the identification of specific landforms. This is also known as geomorphometry, in modern usage, this involves generation of elevation data in digital form. It is often considered to include the representation of the landform on a map by a variety of techniques, including contour lines, hypsometric tints. The term topography originated in ancient Greece and continued in ancient Rome, the word comes from the Greek τόπος and -γραφία. In classical literature this refers to writing about a place or places, in Britain and in Europe in general, the word topography is still sometimes used in its original sense. Detailed military surveys in Britain were called Ordnance Surveys, and this term was used into the 20th century as generic for topographic surveys, the earliest scientific surveys in France were called the Cassini maps after the family who produced them over four generations. The term topographic surveys appears to be American in origin, the earliest detailed surveys in the United States were made by the “Topographical Bureau of the Army, ” formed during the War of 1812, which became the Corps of Topographical Engineers in 1838. In the 20th century, the term started to be used to describe surface description in other fields where mapping in a broader sense is used. An objective of topography is to determine the position of any feature or more generally any point in terms of both a horizontal coordinate system such as latitude, longitude, and altitude, identifying features, and recognizing typical landform patterns are also part of the field. There are a variety of approaches to studying topography, which method to use depend on the scale and size of the area under study, its accessibility, and the quality of existing surveys. Work on one of the first topographic maps was begun in France by Giovanni Domenico Cassini, in areas where there has been an extensive direct survey and mapping program, the compiled data forms the basis of basic digital elevation datasets such as USGS DEM data. This data must often be cleaned to eliminate discrepancies between surveys, but it forms a valuable set of information for large-scale analysis. The original American topographic surveys involved not only recording of relief, remote sensing is a general term for geodata collection at a distance from the subject area. Besides their role in photogrammetry, aerial and satellite imagery can be used to identify and delineate terrain features, certainly they have become more and more a part of geovisualization, whether maps or GIS systems
39.
Early world maps
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The earliest known world maps date to classical antiquity, the oldest examples of the 6th to 5th centuries BCE still based on the flat Earth paradigm. World maps assuming a spherical Earth first appear in the Hellenistic period, a Babylonian world map, known as the Imago Mundi, is commonly dated to the 6th century BCE. The accompanying text mentions seven outer regions beyond the encircling ocean, the descriptions of five of them have survived, the third island is where the winged bird ends not his flight, i. e. cannot reach. On the fourth island the light is brighter than that of sunset or stars, it lay in the northwest, the fifth island, due north, lay in complete darkness, a land where one sees nothing, and the sun is not visible. The sixth island, where a horned bull dwells and attacks the newcomer the seventh island lay in the east and is where the morning dawns. Anaximander is credited with having created one of the first maps of the world and this was all surrounded by the ocean. Hecataeus of Miletus is credited with a work entitled Ges Periodos, one on Europe, is essentially a periplus of the Mediterranean, describing each region in turn, reaching as far north as Scythia. The other book, on Asia, is arranged similarly to the Periplus of the Erythraean Sea of which a version of the 1st century CE survives. The work only survives in some 374 fragments, by far the majority being quoted in the geographical lexicon Ethnika compiled by Stephanus of Byzantium, Eratosthenes drew an improved world map, incorporating information from the campaigns of Alexander the Great and his successors. Asia became wider, reflecting the new understanding of the size of the continent. Eratosthenes was also the first geographer to incorporate parallels and meridians within his cartographic depictions and his work about the ocean and the adjacent areas was a general geographical discussion, showing how all the forces had an effect on each other and applied also to human life. He measured the Earths circumference by reference to the position of the star Canopus and his measure of 240,000 stadia translates to 24,000 miles, close to the actual circumference of 24,901 miles. He was informed in his approach by Eratosthenes, who a century used the elevation of the Sun at different latitudes. Both mens figures for the Earths circumference were uncannily accurate, aided in each case by mutually compensating errors in measurement, Strabo is mostly famous for his 17-volume work Geographica, which presented a descriptive history of people and places from different regions of the world known to his era. The Geographica first appeared in Western Europe in Rome as a Latin translation issued around 1469, Geographica provides a valuable source of information on the ancient world, especially when this information is corroborated by other sources. Within the books of Geographica is a map of Europe, whole world maps according to Strabo are reconstructions from his written text. Marinus of Tyres world maps were the first in the Roman Empire to show China, around 120 CE, Marinus wrote that the habitable world was bounded on the west by the Fortunate Islands. The text of his geographical treatise however is lost and he also invented the equirectangular projection, which is still used in map creation today
40.
History of cartography
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Cartography, or mapmaking, has been an integral part of the human history for thousands of years. Maps began as drawings but can also adopt three-dimensional shapes. The term cartography is modern, loaned into English from French cartographie in the 1840s, the earliest known maps are of the stars, not the earth. Dots dating to 16,500 BC found on the walls of the Lascaux caves map out part of the night sky, the Cuevas de El Castillo in Spain contain a dot map of the Corona Borealis constellation dating from 12,000 BC. Cave painting and rock carvings used simple visual elements that may have aided in recognizing landscape features, another ancient picture that resembles a map was created in the late 7th millennium BC in Çatalhöyük, Anatolia, modern Turkey. This wall painting may represent a plan of this Neolithic village, however, Maps in Ancient Babylonia were made by using accurate surveying techniques. For example, a 7.6 ×6.8 cm clay tablet found in 1930 at Ga-Sur, near contemporary Kirkuk, cuneiform inscriptions label the features on the map, including a plot of land described as 354 iku that was owned by a person called Azala. Most scholars date the tablet to the 25th to 24th century BC, Leo Bagrow dissents with a date of 7000 BC. Hills are shown by overlapping semicircles, rivers by lines, the map also is marked to show the cardinal directions. An engraved map from the Kassite period of Babylonian history shows walls, in contrast, the Babylonian World Map, the earliest surviving map of the world, is a symbolic, not a literal representation. It deliberately omits peoples such as the Persians and Egyptians, who were known to the Babylonians. The area shown is depicted as a circular shape surrounded by water, examples of maps from ancient Egypt are quite rare. Its originality can be seen in the inscriptions, its precise orientation. In reviewing the literature of early geography and early conceptions of the earth, all lead to Homer. Regardless of the doubts about Homers existence, one thing is certain, Homers knowledge of the Earth was very limited. He and his Greek contemporaries knew very little of the Earth beyond Egypt as far south as the Libyan desert, the south-west coast of Asia Minor, furthermore, the coast of the Black Sea was only known through myths and legends that circulated during his time. In his poems there is no mention of Europe and Asia as geographical concepts and that is why the big part of Homers world that is portrayed on this interpretive map represents lands that border on the Aegean Sea. Additional statements about ancient geography may be found in Hesiods poems, through the lyrics of Works and Days and Theogony he shows to his contemporaries some definite geographical knowledge. He introduces the names of rivers as Nile, Ister, the shores of the Bosporus, and the Euxine, the coast of Gaul, the island of Sicily
41.
Cartogram
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A cartogram is a map in which some thematic mapping variable – such as travel time, population, or Gross National Product – is substituted for land area or distance. The geometry or space of the map is distorted in order to convey the information of this alternate variable and they are primarily used to display emphasis and for analysis as nomographs. Two common types of cartograms, area and distance cartograms, Cartograms have a fairly long history, with examples from the mid-1800s. Other synonyms in use are anamorphic map, density-equalizing map and Gastner map, area cartograms may be contiguous or noncontiguous. The area cartograms shown on this page are all contiguous, while an example of a noncontiguous cartogram was published in The New York Times. This method of creation is sometimes referred to as the projector method or scaled-down regions. Cartograms may be classified also by the properties of shape and topology preservation, classical area cartograms are typically distorting the shape of spatial units to some degree, but they are strict at preserving correct neighborhood relationships between them. Another branch of cartograms introduced by Dorling, replaces actual shapes with circles scaled according to the mapped feature, circles are distributed to resemble the original topology. Demers cartogram is a variation of Dorling cartogram, but it uses rectangles instead of circles, schematic maps based on quad trees can be seen as non shape-preserving cartograms with some degree of neighborhood preservation. A collection of about 700 contiguous area cartograms is available at Worldmapper, one of the first cartographers to generate cartograms with the aid of computer visualization was Waldo Tobler of UC Santa Barbara in the 1960s. Prior to Toblers work, cartograms were created by hand, the National Center for Geographic Information and Analysis located on the UCSB campus maintains an online Cartogram Central with resources regarding cartograms. A number of software packages generate cartograms, examples of cartogram software include ScapeToad, Cart, and the Cartogram Processing Tool, which all use the Gastner-Newman algorithm. An alternative algorithm, Carto3F, is implemented as an independent program for non-commercial use on Windows platforms. This program also provides an optimization to the original Dougenik rubber-sheet algorithm, choropleth map Contour map Thematic map Campbell, John. Area cartograms, Their use and creation, concepts and Techniques in Modern Geography series no.59. Norwich, University of East Anglia,1996, Gastner, Michael T. and Mark E. J. Newman, Diffusion-based method for producing density-equalizing maps. Proceedings of the National Academy of Sciences 2004,101, 7499–7504, places in the News, The Use of Cartograms in Introductory Geography Courses. Hennig, Benjamin D. Rediscovering the World, Map Transformations of Human, house, Donald H. and Christopher Kocmoud, Continuous Cartogram Construction
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Choropleth map
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The choropleth map provides an easy way to visualize how a measurement varies across a geographic area or it shows the level of variability within a region. The earliest known choropleth map was created in 1826 by Baron Pierre Charles Dupin, the term choroplethe map was introduced in 1938 by the geographer John Kirtland Wright in Problems in Population Mapping. Choropleth maps are based on data aggregated over previously defined regions, in contrast to area-class and isarithmic maps. Thus, where defined regions are important to a discussion, as in a map divided by electoral regions. The dasymetric technique can be thought of as an approach in many situations. Broadly speaking choropleths represent two types of data, spatially extensive or spatially intensive, spatially extensive data are things like populations. The population of the UK might be 65 million, but it would not be accurate to arbitrarily cut the UK into two halves of equal area and say that the population of half of the UK is 32.5 million. Spatially intensive data are things like rates, densities and proportions, another common error in choropleths is the use of raw data values to represent magnitude rather than normalized values to produce a map of densities. Compare the circled features in the maps at right, there are several different types of color progressions used by cartographers. The following are described in detail in Robinson et al, single-hue progressions fade from a dark shade of the chosen color to a very light or white shade of relatively the same hue. This is a method used to map magnitude. The darkest hue represents the greatest number in the data set, two variables may be shown through the use of two overprinted single color scales. The hues typically used are red to white for the first data set and blue to white for the second. These type of show the magnitude of the values in relation to each other. For example, a typical progression when mapping temperatures is from dark blue to red with white in the middle. When one extreme can be considered better than the other then it is common to denote the poor alternative with shades of red, complementary hue progressions are a type of bi-polar progression. This can be done any of the complementary colors and will fade from each of the darker end point hues into a gray shade representing the middle. An example would be using blue and yellow as the two end points, blended hue progressions use related hues to blend together the two end point hues
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Geologic map
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A geologic map or geological map is a special-purpose map made to show geological features. Rock units or geologic strata are shown by color or symbols to indicate where they are exposed at the surface, stratigraphic contour lines may be used to illustrate the surface of a selected stratum illustrating the subsurface topographic trends of the strata. Isopach maps detail the variations in thickness of stratigraphic units and it is not always possible to properly show this when the strata are extremely fractured, mixed, in some discontinuities, or where they are otherwise disturbed. Rock units are represented by colors. Instead of colors, certain symbols can be used, different geologic mapping agencies and authorities have different standards for the colors and symbols to be used for rocks of differing types and ages. Geologists take two major types of measurements, orientations of planes and orientations of lines. Orientations of planes are often measured as a strike and dip, while orientations of lines are measured as a trend. The angle that the bed makes with the horizontal, along the dip direction, is next to the dip line. In the azimuthal system, strike and dip are often given as strike/dip, trend and plunge are used for linear features, and their symbol is a single arrow on the map. The arrow is oriented in the direction of the linear feature and at the end of the arrow. Trend and plunge are often notated as PLUNGE → TREND, the oldest preserved geologic map is the Turin papyrus, which shows the location of building stone and gold deposits in Egypt. The earliest geologic map of the era is the 1771 Map of Part of Auvergne, or figures of, The Current of Lava in which Prisms, Balls. To be used with Mr. Demarests theories of this hard basalt, pasumot and Daily, Geological Engineers of the King. This map is based on Nicolas Desmarests 1768 detailed study of the geology and eruptive history of the Auvergne volcanoes and he identified both landmarks as features of extinct volcanoes. The 1798 report was incorporated in the 1771 Royal Academy of Science compendium, the first geological map of the U. S. was produced in 1809 by William Maclure. In 1807, Maclure undertook the task of making a geological survey of the United States. He traversed and mapped nearly every state in the Union, during the rigorous two-year period of his survey, he crossed and recrossed the Allegheny Mountains some 50 times. Maclures map shows the distribution of five classes of rock in what are now only the states of the present-day US
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Nautical chart
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A nautical chart is a graphic representation of a maritime area and adjacent coastal regions. Nautical charts are essential tools for marine navigation, many countries require vessels, especially commercial ships, Nautical charting may take the form of charts printed on paper or computerized electronic navigational charts. With each daily download, critical data such as Local Notice to Mariners is added to the on-demand chart files so that these charts will be up to date at the time of printing, Nautical charts are based on hydrographic surveys. As surveying is laborious and time-consuming, hydrographic data for many areas of sea may be dated, depths are measured in a variety of ways. Historically the sounding line was used, in modern times, echo sounding is used for measuring the seabed in the open sea. When measuring the depth of water over an entire obstruction, such as a shipwreck. This ensures that difficult to find projections, such as masts, Nautical charts are issued by power of the national hydrographic offices in many countries. These charts are considered official in contrast to those made by commercial publishers, many hydrographic offices provide regular, sometimes weekly, manual updates of their charts through their sales agents. Individual hydrographic offices produce national chart series and international chart series, there are also commercially published charts, some of which may carry additional information of particular interest, e. g. for yacht skippers. The nature of a waterway depicted by a chart may change, therefore, old or uncorrected charts should never be used for navigation. Every producer of nautical charts also provides a system to inform mariners of changes that affect the chart. In the U. S. NOAA also has a partner who prints the POD NOAA charts. To give notice to mariners, radio broadcasts provide advance notice of urgent corrections, a good way to keep track of corrections is with a Chart and Publication Correction Record Card system. When the time comes to use the chart, he pulls the chart and charts card and this system ensures that every chart is properly corrected prior to use. A prudent mariner should obtain a new chart if he has not kept track of corrections, various Digital Notices to Mariners systems are available on the market such as Digitrace, Voyager, or ChartCo, to correct British Admiralty charts as well as NOAA charts. These systems provide only vessel relevant corrections via e-mail or web downloads, tracings to assist corrections are provided at the same time. The Canadian Coast Guard produces the Notice to Mariners publication which informs mariners of important navigational safety matters affecting Canadian Waters and this electronic publication is published on a monthly basis and can be downloaded from the Notices to Mariners Web site. The information in the Notice to Mariners is formatted to simplify the correction of paper charts, various and diverse methods exist for the correction of electronic navigational charts
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Pictorial map
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Pictorial maps depict a given territory with a more artistic rather than technical style. It is a type of map in contrast to road map, atlas, the cartography can be a sophisticated 3-D perspective landscape or a simple map graphic enlivened with illustrations of buildings, people and animals. They can feature all sorts of varied topics like historical events, legendary figures or local agricultural products, Pictorial maps usually show an area as if viewed from above at an oblique angle. They are not generally drawn to scale in order to show street patterns, individual buildings, some require thousands of hours to produce. Will Durant said that show us the face of History. This is especially true of pictorial maps because their vocation has always been to present a visual message. Throughout the ages, pictorial maps have been used to show the cuisine of a country, the industries of a city, the attractions of a tourist town, the history of a region or its holy shrines. The history of pictorial maps overlaps much with the history of cartography in general, in Medieval cartography, pictorial icons as well as religious and historical ideas usually overshadowed accurate geographic proportions. A classic example of this is the T and O map which represented the three continents in the form of a cross with Jerusalem at its center. The more precise art of illustrating detailed bird’s-eye-view urban landscapes flourished during the European Renaissance, when printing came around, pictorial maps evolved into some of the earliest forms of advertising as cities competed amongst themselves to attract larger shares of the known world’s commerce. As cartography evolved, the art form went its own way. Between 1825 and 1875, the production and collection of maps of cities rose to something of a mania. In the U. S. alone, thousands of maps were produced. The leading panoramic map artists in the U. S. A. were Herman Brosius, Camille N. Drie, Thaddeus Mortimer Fowler, Paul Giraud, Augustus Koch, D. D. Morse, Henry Welge, and A. L. Westyard. Somewhat like the websites of their time, every town had to have one to remain competitive in attracting industry, a vast collection of these prints is maintained by the Library of Congress and many of the more beautiful ones continue to be reprinted and sold to this day. With the growth of tourism, pictorial mapmaking reappeared as a popular art form in the 1920s through the 1950s. Another resurgence occurred in the 1970s and 80s and this was the heyday of companies like Archar and Descartes who produced hundreds of colorful promotional maps of mainly American and Canadian cities. Local businesses were drawn on these Character maps with their logos proudly embedded on their buildings
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Thematic map
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A thematic map is a type of map specifically designed to show a particular theme connected with a specific geographic area. A thematic map is a map that focuses on a theme or subject area. This is in contrast to general maps, which regularly show the variety of phenomena—geological, geographical. The contrast between them lies in the fact that thematic maps use the data, such as coastlines, boundaries and places. General maps portray the base data, such as landforms, lines of transportation, settlements, thematic maps emphasize spatial variation of one or a small number of geographic distributions. These distributions may be physical phenomena such as climate or human characteristics such as population density, barbara Petchenik described the difference as in place, about space. While general reference maps show where something is in space, thematic maps tell a story about that place, thematic maps are sometimes referred to as graphic essays that portray spatial variations and interrelationships of geographical distributions. Location, of course, is important to provide a base of where selected phenomena are occurring. An important cartographic element preceding thematic mapping was the development of base maps. Improvements in accuracy proceeded at a pace, and even until the mid-17th century. Still, base maps around this time were good enough to display appropriate information and his first significant cartographic contribution was a star chart of the constellation of the Southern Hemisphere, made during his stay on St. Helena and published on 1686. In that same year he published his first terrestrial map in an article about trade winds. In 1701 he published the New and Correct Chart Shewing the Variations of the Compass, see first image, another example of early thematic mapping comes from London physician John Snow. Though disease had been mapped thematically, Snow’s cholera map in 1854 is the best known example of using maps for analysis. Essentially, his technique and methodology anticipate principles of an information system. Starting with a base map of a London neighborhood which included streets and water pump locations. The emerging pattern centered around one particular pump on Broad Street, at Snow’s request, the handle of the pump was removed, and new cholera cases ceased almost at once. Further investigation of the area revealed the Broad Street pump was near a cesspit under the home of the outbreaks first cholera victim, another 19th century example of thematic maps, according to Friendly, was the earliest known choropleth map in 1826 created by Charles Dupin
