An Atlas of Fantasy, compiled by Jeremiah Benjamin Post, was originally published in 1973 by Mirage Press and revised for a 1979 edition by Ballantine Books. The 1979 edition dropped twelve maps from the first edition and added fourteen new ones. It also included an introduction by Lester del Rey.
To remain of manageable size, the Atlas excludes advertising maps, cartograms, most disproportionate maps, and alternate history ("might have been") maps, focusing instead on imaginary lands derived from literary sources. It purposefully omits "one-to-one" maps such as Thomas Hardy's Wessex (which merely renames places in southwest England), but includes Barsetshire and Yoknapatawpha County, which are evidently considered to be sufficiently fictionalized. The emphasis is on science fiction and fantasy, though Post suggests there exist enough mystery fiction maps to someday create The Detectives' Handy Pocket Atlas. Other maps were omitted due to permission costs or reproduction quality.
The maps are reproduced from many sources, and an Index of Artists is included.
- "An Atlas of Fantasy" | 2016-07-13 | 52 Upvotes 15 Comments
The Hajnal line is a border that links Saint Petersburg, Russia and Trieste, Italy. In 1965, John Hajnal discovered it divides Europe into two areas characterized by different levels of nuptiality. To the west of the line, marriage rates and thus fertility were comparatively low and a significant minority of women married late or remained single; to the east of the line and in the Mediterranean and select pockets of Northwestern Europe, early marriage was the norm and high fertility was countered by high mortality.
- "Hajnal line" | 2018-09-30 | 102 Upvotes 38 Comments
Muḥammad ibn Mūsā al-Khwārizmī (Persian: Muḥammad Khwārizmī محمد بن موسی خوارزمی; c. 780 – c. 850), Arabized as al-Khwarizmi with al- and formerly Latinized as Algorithmi, was a Persian polymath who produced works in mathematics, astronomy, and geography. Around 820 CE he was appointed as the astronomer and head of the library of the House of Wisdom in Baghdad.
Al-Khwarizmi's popularizing treatise on algebra (The Compendious Book on Calculation by Completion and Balancing, c. 813–833 CE) presented the first systematic solution of linear and quadratic equations. One of his principal achievements in algebra was his demonstration of how to solve quadratic equations by completing the square, for which he provided geometric justifications. Because he was the first to treat algebra as an independent discipline and introduced the methods of "reduction" and "balancing" (the transposition of subtracted terms to the other side of an equation, that is, the cancellation of like terms on opposite sides of the equation), he has been described as the father or founder of algebra. The term algebra itself comes from the title of his book (specifically the word al-jabr meaning "completion" or "rejoining"). His name gave rise to the terms algorism and algorithm. His name is also the origin of (Spanish) guarismo and of (Portuguese) algarismo, both meaning digit.
In the 12th century, Latin translations of his textbook on arithmetic (Algorithmo de Numero Indorum) which codified the various Indian numerals, introduced the decimal positional number system to the Western world. The Compendious Book on Calculation by Completion and Balancing, translated into Latin by Robert of Chester in 1145, was used until the sixteenth century as the principal mathematical text-book of European universities.
In addition to his best-known works, he revised Ptolemy's Geography, listing the longitudes and latitudes of various cities and localities. He further produced a set of astronomical tables and wrote about calendaric works, as well as the astrolabe and the sundial. He also made important contributions to trigonometry, producing accurate sine and cosine tables, and the first table of tangents.
- "Muhammad ibn Musa al-Khwarizmi" | 2016-04-06 | 14 Upvotes 1 Comments
The Piri Reis map is a world map compiled in 1513 by the Ottoman admiral and cartographer Piri Reis (pronounced [piːˈɾiː ɾeis]). Approximately one third of the map survives; it shows the western coasts of Europe and North Africa and the coast of Brazil with reasonable accuracy. Various Atlantic islands, including the Azores and Canary Islands, are depicted, as is the mythical island of Antillia and possibly Japan.
The map's historical importance lies in its demonstration of the extent of global exploration of the New World by approximately 1510, and in its claim to have used a map of Christopher Columbus, otherwise lost, as a source. Piri also stated that he had used ten Arab sources and four Indian maps sourced from the Portuguese. More recently, the map has been the focus of claims for the pre-modern exploration of the Antarctic coast.
The Piri Reis map is in the Library of the Topkapı Palace in Istanbul, Turkey, but is not usually on display to the public.
- "Piri Reis Map" | 2014-07-18 | 61 Upvotes 12 Comments
Due to national security concerns, the use of geographic information in the People's Republic of China is restricted to entities that obtain a special authorization from the administrative department for surveying and mapping under the State Council. Consequences of the restriction include fines for unauthorized surveys, lack of geotagging information on many cameras when the GPS chip detects a location within China, incorrect alignment of street maps with satellite maps in various applications, and seeming unlawfulness of crowdsourced mapping efforts such as OpenStreetMap.
In cartography, a trap street is a fictitious entry in the form of a misrepresented street on a map, often outside the area the map nominally covers, for the purpose of "trapping" potential copyright violators of the map who, if caught, would be unable to explain the inclusion of the "trap street" on their map as innocent. On maps that are not of streets, other "copyright trap" features (such as nonexistent towns, or mountains with the wrong elevations) may be inserted or altered for the same purpose.
Trap streets are often nonexistent streets; but sometimes, rather than actually depicting a street where none exists, a map will misrepresent the nature of a street in a fashion that can still be used to detect copyright violators but is less likely to interfere with navigation. For instance, a map might add nonexistent bends to a street, or depict a major street as a narrow lane, without changing its location or its connections to other streets.
Trap streets are rarely acknowledged by publishers. One known case is a popular driver's atlas for the city of Athens, Greece, which has a warning inside its front cover that potential copyright violators should beware of trap streets.
The Waldseemüller map or Universalis Cosmographia ("Universal Cosmography") is a printed wall map of the world by German cartographer Martin Waldseemüller, originally published in April 1507. It is known as the first map to use the name "America". The name America is placed on what is now called South America on the main map. As explained in Cosmographiae Introductio, the name was bestowed in honor of the Italian Amerigo Vespucci.
The map is drafted on a modification of Ptolemy's second projection, expanded to accommodate the Americas and the high latitudes. A single copy of the map survives, presently housed at the Library of Congress in Washington, D.C.
Waldseemüller also created globe gores, printed maps designed to be cut out and pasted onto spheres to form globes of the Earth. The wall map, and his globe gores of the same date, depict the American continents in two pieces. These depictions differ from the small inset map in the top border of the wall map, which shows the two American continents joined by an isthmus.
- "Waldseemüller map" | 2014-05-16 | 39 Upvotes 24 Comments
Yahoo! Pipes was a web application from Yahoo! that provided a graphical user interface for building data mashups that aggregate web feeds, web pages, and other services, creating Web-based apps from various sources, and publishing those apps. The application worked by enabling users to "pipe" information from different sources and then set up rules for how that content should be modified (for example, filtering). Other than the pipe editing page, the website had a documentation page and a discussion page. The documentation page contained information about pipes including guides for the pipe editor and troubleshooting. The discussion page enabled users to discuss the pipes with other users.
Mao Kun map, usually referred to in modern Chinese sources as Zheng He's Navigation Map (simplified Chinese: 郑和航海图; traditional Chinese: 鄭和航海圖; pinyin: Zhèng Hé hánghǎi tú), is a set of navigation charts published in the Ming dynasty military treatise Wubei Zhi. The book was compiled by Mao Yuanyi in 1621 and published in 1628; the name of the map refers to his grandfather Mao Kun (Chinese: 茅坤; pinyin: Máo Kūn) from whose library the map is likely to have originated. The map is often regarded as a surviving document from the expeditions of Zheng He in addition to accounts written by Zheng's officers, such as Yingya Shenglan by Ma Huan, Xingcha Shenglan by Fei Xin, and Xiyang Fanguo Zhi by Gong Zhen. It is the earliest Chinese map to give an adequate representation of Southern Asia, Persia, Arabia and East Africa.
- "Mao Kun Map" | 2020-07-26 | 44 Upvotes 23 Comments
The coastline paradox is the counterintuitive observation that the coastline of a landmass does not have a well-defined length. This results from the fractal curve-like properties of coastlines, i.e., the fact that a coastline typically has a fractal dimension (which in fact makes the notion of length inapplicable). The first recorded observation of this phenomenon was by Lewis Fry Richardson and it was expanded upon by Benoit Mandelbrot.
The measured length of the coastline depends on the method used to measure it and the degree of cartographic generalization. Since a landmass has features at all scales, from hundreds of kilometers in size to tiny fractions of a millimeter and below, there is no obvious size of the smallest feature that should be taken into consideration when measuring, and hence no single well-defined perimeter to the landmass. Various approximations exist when specific assumptions are made about minimum feature size.
The problem is fundamentally different from the measurement of other, simpler edges. It is possible, for example, to accurately measure the length of a straight, idealized metal bar by using a measurement device to determine that the length is less than a certain amount and greater than another amount—that is, to measure it within a certain degree of uncertainty. The more accurate the measurement device, the closer results will be to the true length of the edge. When measuring a coastline, however, the closer measurement does not result in an increase in accuracy—the measurement only increases in length; unlike with the metal bar, there is no way to obtain a maximum value for the length of the coastline.
In three-dimensional space, the coastline paradox is readily extended to the concept of fractal surfaces whereby the area of a surface varies, depending on the measurement resolution.
- "Coastline Paradox" | 2020-09-10 | 63 Upvotes 32 Comments