Amerigo Vespucci was an Italian explorer, financier and cartographer, born in the Republic of Florence. He became a citizen of the Crown of Castile in 1505. Around 1502, Vespucci demonstrated that Brazil and the West Indies were not Asia's eastern outskirts but a separate, unexplored land mass colloquially known as the New World, it came to be called "the Americas", a name derived from Americus. Vespucci was raised in Florence, on the Italian Peninsula, he was the third son of Ser Nastagio Vespucci, a Florentine notary, Lisabetta Mini. His family lived near All Saints' Church in Ognissanti, known as San Salvatore, which may have influenced his naming of the Bay of All Saints and the city of Salvador, Bahia. Vespucci was educated by his uncle, Giorgio Antonio Vespucci, a Dominican friar in the monastery of San Marco in Florence. Although his elder brothers were sent to the University of Pisa to pursue scholastic careers, Amerigo embraced a mercantile life and was hired as a clerk by the Florentine house of Medici.
Vespucci's patron was Lorenzo di Pierfrancesco de' Medici, who became head of the business after the elder Lorenzo's death in 1492. The Medici dispatched Donato Niccolini and the 38-year-old Vespucci in March 1492 as confidential agents to investigate the Medici branch office in Cádiz, whose managers were under suspicion. In April 1495, due to the intrigues of Bishop Juan Rodríguez de Fonseca, the Crown of Castile broke their monopoly deal with Christopher Columbus and began licensing other navigators for the West Indies. Around this time, Vespucci was engaged as executor of the estate of Giannotto Berardi, an Italian merchant who had died in Seville. Vespucci organized the fulfillment of Berardi's contract with the Castilian crown to provide twelve vessels for the Indies. After they were delivered, he continued as a provisions contractor for Indies expeditions and is known to have secured beef for at least one of Columbus' voyages. Vespucci's expeditions became known in Europe after two accounts attributed to him were published between 1502 and 1503.
In 1507, Martin Waldseemüller produced a world map on which he named the new continent America after the feminine Latin version of Vespucci's first name. In an accompanying book, Waldseemüller published one of the Vespucci accounts; the 18th-century rediscovery of other letters by Vespucci has led to the view that the early published accounts could be fabrications, not by Vespucci but by others. Two letters attributed to Vespucci were published during his lifetime. Mundus Novus was a Latin translation of a lost Italian letter sent from Lisbon to Lorenzo di Pierfrancesco de' Medici describing a voyage to South America in 1501–1502, it was published in late 1502 or early 1503 and reprinted and distributed in a number of European countries. Lettera di Amerigo Vespucci delle isole nuovamente trovate in quattro suoi viaggi, known as Lettera al Soderini or just Lettera, was a letter in Italian addressed to Piero Soderini, published in 1504 or 1505, it was a purported account of four voyages to the Americas made by Vespucci between 1497 and 1504.
A Latin translation was published by Martin Waldseemüller in 1507 in Cosmographiae Introductio as Quattuor Americi Vespucij navigationes, a book on cosmography and geography. On March 22, 1508, King Ferdinand made Vespucci chief navigator of Spain at a large salary and commissioned him to found a school of navigation to standardize and modernize navigation techniques used by Iberian sea captains exploring the world. Vespucci developed a rudimentary but accurate method of determining longitude, improved by more accurate chronometers. During the 18th century, three unpublished letters were rediscovered from Vespucci to Lorenzo de' Medici. One describes a voyage made in 1499–1500 which corresponds with the second of the four reported voyages. Another was written from Cape Verde in 1501 in the early part of the third voyages, before crossing the Atlantic; the third letter was sent from Lisbon after the completion of that voyage. It has been suggested that Vespucci exaggerated his role and created deliberate fabrications in the two letters published during his lifetime.
Scholars now believe. The publication and widespread circulation of the letters may have led Waldseemüller to name the new continent America on his 1507 world map in Lorraine. Vespucci used a Latinized form of his name in his Latin writings, which Waldseemüller used as a base for the new name in its feminine form. According to the book accompanying the map, "I do not see what right any one would have to object to calling this part, after Americus who discovered it and, a man of intelligence, that is, the Land of Americus, or America: since both Europa and Asia got their names from women". Vespucci may not have been aware; the two disputed letters say. It is disputed as to.
A map projection is a systematic transformation of the latitudes and longitudes of locations from the surface of a sphere or an ellipsoid into locations on a plane. Maps cannot be created without map projections. All map projections distort the surface in some fashion. Depending on the purpose of the map, some distortions are acceptable and others are not. There is no limit to the number of possible map projections. More the surfaces of planetary bodies can be mapped if they are too irregular to be modeled well with a sphere or ellipsoid. More projections are a subject of several pure mathematical fields, including differential geometry, projective geometry, manifolds. However, "map projection" refers to a cartographic projection. Maps can be more useful than globes in many situations: they are more compact and easier to store; these useful traits of maps motivate the development of map projections. However, Carl Friedrich Gauss's Theorema Egregium proved that a sphere's surface cannot be represented on a plane without distortion.
The same applies to other reference surfaces used as models for the Earth, such as oblate spheroids and geoids. Since any map projection is a representation of one of those surfaces on a plane, all map projections distort; 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, or the rectilinear image produced by a pinhole camera on a flat film plate. 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. In reality, the Earth and other large celestial bodies are better modeled as oblate spheroids, whereas small objects such as asteroids have irregular shapes. Io is better modeled by triaxial prolated spheroid with small eccentricities. Haumea's shape is a Jacobi ellipsoid, with its major axis twice as long as its minor and with its middle axis one and half times as long as its minor.
These other surfaces can be mapped as well. Therefore, more a map projection is any method of "flattening" a continuous curved surface onto a plane. Many properties can be measured on the Earth's surface independent of its geography; some of these properties are: Area Shape Direction Bearing Distance ScaleMap projections can be constructed to preserve at least one of these properties, though only in a limited way for most. Each projection compromises, or approximates basic metric properties in different ways; the purpose of the map determines. 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. Different datums assign different coordinates to the same location, so in large scale maps, such as those from national mapping systems, it is important to match the datum to the projection; the slight differences in coordinate assignation between different datums is not a concern for world maps or other vast territories, where such differences get shrunk to imperceptibility.
The classical way of showing the distortion inherent in a projection is to use Tissot's indicatrix. For a given point, using the scale factor h along the meridian, the scale factor k along the parallel, the angle θ′ between them, Nicolas Tissot described how to construct an ellipse that characterizes the amount and orientation of the components of distortion. By spacing the ellipses along the meridians and parallels, the network of indicatrices shows how distortion varies across the map; the creation of a map projection involves two steps: Selection of a model for the shape of the Earth or planetary body. Because the Earth's actual shape is irregular, information is lost in this step. Transformation of geographic coordinates to Cartesian or polar plane coordinates. In large-scale maps, Cartesian coordinates have a simple relation to eastings and northings defined as a grid superimposed on the projection. In small-scale maps and northings are not meaningful, grids are not superimposed; some of the simplest map projections are literal projections, as obtained by placing a light source at some definite point relative to the globe and projecting its features onto a specified surface.
This is not the case for most projections, which are defined only in terms of mathematical formulae that have no direct geometric interpretation. However, picturing the light source-globe model can be helpful in understanding the basic concept of a map projection A surface that can be unfolded or unrolled into a plane or sheet without stretching, tearing or shrinking is called a developable surface; the cylinder and the plane are all developable surfaces. The sphere and ellipsoid do not have developable surfaces, so any projection of them onto a plane will have to dis
Johannes Schöner was a renowned and respected German polymath. It is best to refer to him using the usual 16th-century Latin term "mathematicus", as the areas of study to which he devoted his life were different from those now considered to be the domain of the mathematician, he was a priest, astrologer, cosmographer, mathematician and scientific instrument maker and editor and publisher of scientific tests. In his own time he enjoyed a European wide reputation as an innovative and influential globe maker and cosmographer and as one of the continent's leading and most authoritative astrologers. Today he is remembered as an influential pioneer in the history of globe making and as a man who played a significant role in the events that led up to the publishing of Copernicus' "De revolutionibus" in Nürnberg in 1543. Schöner was born on 16 January 1477 in Karlstadt am Main in Lower Franconia; as with most Renaissance scholars nothing is known about his early life. All, known is that he had a brother, Peter, to whom he addressed his "Arzneibuch" in 1528.
Quite detailed information for Schöner’s adult life, at least up to 1506, has been preserved in his own marginalia in his copy of Regiomontanus' printed Ephemerides, which he used as a diary. He matriculated at the University of Erfurt in the winter semester 1494/5 and graduated Baccalaureus on 21 March 1498, he was appointed to a position in the school in Gemünden on 22 February 1499 and ordained as a Catholic priest in the Bishopric of Bamberg on 13 June 1500. On 2 February 1500 he moved to Bamberg and was appointed chaplain in Hallstatt near Bamberg on 18 April 1500, his next appointment was as vicar in his hometown Karlstadt from 4 June 1504. Between 4 May and 29 October 1506 he was again in Bamberg, his diary informs us that he entered a relationship with Kunigunde Holocher in 1499, with whom he had three children: a son Johannes born on 1 February 1502, a daughter Sibilla born on 12 June 1503 and a second son Vitus born on 21 November 1504. Schöner was the owner of the only specimen of the 1507 Waldseemüller map of the world that has survived and, rediscovered at Schloss Wolfegg in Upper Swabia in 1901.
Since 2003 it is in possession of the Library of Congress. No diary exists after 1506, up to 1515 there are only indirect traces of Schöner's existence in the financial records of the bishopric and in the correspondence of Lorenz Beheim, who after 24 years in Rome as chamberlain to Pope Alexander IV had returned to Bamberg in 1505 as a canon of the cathedral. 1526, he was called to Nürnberg as the first professor of mathematics at the newly founded gymnasium Aegidianum, a post he held till one year prior to his death. At the same time, he married. In Bamberg, he owned his own printing company and published many maps and globes; the first printed globe of the sky was made in his workshop in 1515. He made another globe in 1520. Schöner had made still unpublished data of Mercury observations from Walther available to Copernicus, 45 observations in total, 14 of them with longitude and latitude. Copernicus used three of them in "De revolutionibus", giving only longitudes, falsely attributing them to Schöner.
The values differed from the ones published by Schöner in 1544. 1538, Georg Joachim Rheticus, a young professor of mathematics at Wittenberg and former assistant of Copernicus, stayed for some time with Schöner who convinced him to visit Nicolaus Copernicus in Frauenburg. In 1540, Rheticus dedicated the first published report of Copernicus work, the Narratio prima, to Schöner, to test the waters of the reaction by the Catholic Church; as this was well received, Copernicus agreed to publish his main work, Rheticus prepared Copernicus' manuscript for printing. In Nürnberg, Schöner published in 1544 the astronomical observations of Regiomontanus and Walther, as well as manuscripts of Regiomontanus, in the hand of Walther, as Observationes XXX annorum a I. Regiomontano et B. Walthero Norimbergae habitae. A crater on Mars is named in his honor. Johannes Schöner globe Ancient world maps World map From the Lessing J. Rosenwald Collection at the Library of Congress: Joannis Schoneri Carolostadii Opusculum Astrologicum Opera mathematica Ioannis Schoneri in vnvm volvmen congesta...
Luculentissima quaedam terrae totius descriptio. At: Carolostadii Opusculum astrologicum. From the Rare Book and Special Collection Division at the Library of Congress
Martin Waldseemüller was a German cartographer. He and Matthias Ringmann are credited with the first recorded usage of the word America, on the 1507 map Universalis Cosmographia in honour of the Italian explorer Amerigo Vespucci. Waldseemüller was born in Wolfenweiler near Freiburg im Breisgau and he studied at the University of Freiburg. On 25 April 1507, as a member of the Gymnasium Vosagense at Saint Diey in the Duchy of Lorraine, he produced a globular world map and a large 12-panel world wall map using the information from Columbus and Vespucci's travels, both bearing the first use of the name "America"; the globular and wall maps were accompanied by a book Cosmographiae Introductio, an introduction to cosmography. The book, first printed in the city of Saint-Dié-des-Vosges, includes in its second part, a translation to Latin of the Quattuor Americi Vespuccij navigationes, a letter written by Amerigo Vespucci, although some historians consider it to have been a forgery written by its supposed recipient in Italy.
In the seventh chapter of the Cosmographiæ Introduction, written by Matthias Ringmann, it is explained why the name America was proposed for the New World, or the Fourth Part of the World: Atque in sexto climate Antarcticum versus et pars extrema Africæ nuper reperta.... Et quarta orbis pars sitae sunt Translation: And in the sixth climate toward the Antarctic, the discovered farther part of Africa... and a fourth part of the world are situated In the ninth chapter of the same book the reasons for the name America are given in more detail: Nunc vero et hæ partes sunt latius lustratæ et alia quarta pars per Americum Vesputium inventa est, quam non video cur quis jure vetet ab Americo Inventore sagacis ingenii viro, Amerigen quasi Americi terram sive Americam dicendam. Translation: But now these parts have been more explored, another fourth part has been discovered by Americus Vesputius, I do not see why anyone should justifiably forbid it to be called Amerige, as if "Americus' Land", or America, from its discoverer Americus, a man of perceptive character.
In 1513, Waldseemüller appears to have had second thoughts about the name due to contemporary protests about Vespucci’s role in the discovery and naming of America, or just waiting for the official discovery of the whole northwestern coast of what is now called North America, as separated from East Asia. In his reworking of the Ptolemy atlas, the continent is labelled Terra Incognita. Despite the revision, 1,000 copies of the world maps had since been distributed, the original suggestion took hold. While North America was still called Indies in documents for some time, it was called America as well; the wall map was lost for a long time, but a copy was found in Schloss Wolfegg in southern Germany by Joseph Fischer in 1901. It is still the only copy known to survive, it was purchased by the United States Library of Congress in May 2003 after an agreement was reached in 2001. Five copies of the globular map survive in the form of "gores": printed maps that were intended to be cut out and pasted onto a wooden globe.
Only one of these lies in the Americas today, residing at the James Ford Bell Library University of Minnesota. Waldseemüller died intestate 16 March 1520 in Sankt Didel a canon of the collegiate Church of Saint-Dié. Waldseemüller map Naming of America Discoverer of the Americas Richard Amerike History of cartography List of Roman Catholic scientist-clerics List of German inventors and discoverers Peter W. Dickson: "The Magellan Myth: Reflections on Columbus and the Waldseemueller Map of 1507", Printing Arts Press, 2007, 2009 John Hessler: The Naming of America: Martin Waldseemüller's 1507 World Map and the Cosmographiae Introductio, Library of Congress, 2007 Seymour Schwartz: Putting "America" on the Map, the Story of the Most Important Graphic Document in the History of the United States, Prometheus Books, New York, 2007 David Brown: 16th-Century Mapmaker's Intriguing Knowledge, in: Washington Post, 2008-11-17, p. A7 Toby Lester: Putting America on the Map, Volume 40, Number 9, p. 78, December 2009 Toby Lester: The Fourth Part of the World, The Epic Story of History's Greatest Map, Profile Books, London, 2009 Chet van Duzer and Benoît Larger: Martin Waldseemüller Death Date, Imago Mundi, Volume 63, Part 2: 219-221, 2011 The Cosmographiæ Introductio of Martin Waldseemüller, via Google Books.
Joseph Fischer. "Martin Waldseemüller". In Herbermann, Charles. Catholic Encyclopedia. New York: Robert Appleton Company. "16th-Century Mapmaker's Intriguing Knowledge", David Brown, The Washington Post. November 17, 2008. "You Are Here—The Library of Congress buys'America's birth certificate'.", John J. Miller, The Wall Street Journal. July 25, 2003. "The map that changed the world", Toby Lester The BBC, October 28, 2009. "Naming of America", BBC. "Waldseemüller, Martin". Appletons' Cyclopædia of American Biography. 1900. World Digital Library presentation of Universalis cosmographia secu
The Waldseemüller map or Universalis Cosmographia is a printed wall map of the world by German cartographer Martin Waldseemüller published in April 1507. It is known as the first map to use the name "America"; the name America is placed on. 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 created globe gores, printed maps designed to be cut out and pasted onto spheres to form globes of the Earth; the wall map, 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; the wall map consists of twelve sections printed from woodcuts measuring 18 by 24.5 inches.
Each section is one of three vertically, when assembled. The map uses a modified Ptolemaic map projection with curved meridians to depict the entire surface of the Earth. In the upper-mid part of the main map there is inset another, miniature world map representing to some extent an alternative view of the world. Longitudes, which were difficult to determine at the time, are given in terms of degrees east from the Fortunate Islands which Waldseemüller locates at the Canary Islands; the longitudes of eastern Asian places are too great. Latitudes, which were easy to determine, are quite far off. For example, "Serraleona" is placed south of the equator, the Cape of Good Hope is placed at 50°S; the full title of the map is Universalis cosmographia secundum Ptholomaei traditionem et Americi Vespucii aliorumque lustrationes. One of the "others" was Christopher Columbus; the title signalled his intention to combine or harmonize in a unified cosmographic depiction the traditional Ptolemaic geography of Europe and Africa with the new geographical information provided by Amerigo Vespucci and his fellow discoverers of lands in the western hemisphere.
He explained: "In designing the sheets of our world-map we have not followed Ptolemy in every respect as regards the new lands... We have therefore followed, on the flat map, except for the new lands and some other things, but on the solid globe, which accompanies the flat map, the description of Amerigo, appended hereto."Several earlier maps are believed to be sources, chiefly those based on the Geography and the Caveri planisphere and others similar to those of Henricus Martellus or Martin Behaim. The Caribbean and what appears to be Florida were depicted on two earlier charts, the Cantino map, smuggled from Portugal to Italy in 1502 showing details known in 1500, the Caverio map, drawn circa 1503–1504 and showing the Gulf of Mexico. While some maps after 1500 show, with ambiguity, an eastern coastline for Asia distinct from the Americas, the Waldseemüller map indicates the existence of a new ocean between the trans-Atlantic regions of the Spanish discoveries and the Asia of Ptolemy and Marco Polo as exhibited on the 1492 Behaim globe.
The first historical records of Europeans to set eyes on this ocean, the Pacific, are recorded as Vasco Núñez de Balboa in 1513. That is. In addition, the map predicts the width of South America at certain latitudes to within 70 miles. However, as pointed out by E. G. Ravenstein, this is an illusory effect of the cordiform projection used by Waldseemüller, for when the map is laid out on a more familiar equirectangular projection and compared with others of the period set out on that same projection there is little difference between them: this is evident when the comparison is made with Johannes Schöner's 1515 globe. Among most map-makers until that time, it was still erroneously believed that the lands discovered by Christopher Columbus and others formed part of the Indies of Asia, thus some believe that it is impossible that Waldseemüller could have known about the Pacific, depicted on his map. The historian Peter Whitfield has theorized that Waldseemüller incorporated the ocean into his map because Vespucci's accounts of the Americas, with their so-called "savage" peoples, could not be reconciled with contemporary knowledge of India and the islands of Indies.
Thus, in the view of Whitfield, Waldseemüller reasoned that the newly discovered lands could not be part of Asia, but must be separate from it, a leap of intuition, proved uncannily precise. An alternative explanation is that of George E. Nunn. Mundus Novus, a book attributed to Vespucci, was published throughout Europe after 1504, including by Waldseemüller's group in 1507, it had first introduced to Europeans the idea. It is theorized that this led to Waldseemüller's separating the Americas from Asia, depicting the Pacific Ocean, the use of the first name of Vespucci on his map. An explanatory text, the Cosmographiae Introductio believed to have been written by Waldseemüller's colleague Matthias Ringmann, accompanied the map, it was said in Chapter IX of that text that the earth was now known to be divided into four parts, of which Eur
The Americas comprise the totality of the continents of North and South America. Together, they comprise the New World. Along with their associated islands, they cover 8% of Earth's total surface area and 28.4% of its land area. The topography is dominated by the American Cordillera, a long chain of mountains that runs the length of the west coast; the flatter eastern side of the Americas is dominated by large river basins, such as the Amazon, St. Lawrence River / Great Lakes basin, La Plata. Since the Americas extend 14,000 km from north to south, the climate and ecology vary from the arctic tundra of Northern Canada and Alaska, to the tropical rain forests in Central America and South America. Humans first settled the Americas from Asia between 17,000 years ago. A second migration of Na-Dene speakers followed from Asia; the subsequent migration of the Inuit into the neoarctic around 3500 BCE completed what is regarded as the settlement by the indigenous peoples of the Americas. The first known European settlement in the Americas was by the Norse explorer Leif Erikson.
However, the colonization never became permanent and was abandoned. The Spanish voyages of Christopher Columbus from 1492 to 1502 resulted in permanent contact with European powers, which led to the Columbian exchange and inaugurated a period of exploration and colonization whose effects and consequences persist to the present. Diseases introduced from Europe and West Africa devastated the indigenous peoples, the European powers colonized the Americas. Mass emigration from Europe, including large numbers of indentured servants, importation of African slaves replaced the indigenous peoples. Decolonization of the Americas began with the American Revolution in the 1770s and ended with the Spanish–American War in the late 1890s. All of the population of the Americas resides in independent countries; the Americas are home to over a billion inhabitants, two-thirds of which reside in the United States, Brazil, or Mexico. It is home to eight megacities: New York City, Mexico City, São Paulo, Los Angeles, Buenos Aires, Rio de Janeiro, Bogotá, Lima.
The name America was first recorded in 1507. Christie's auction house says a two-dimensional globe created by Martin Waldseemüller was the earliest recorded use of the term; the name was used in the Cosmographiae Introductio written by Matthias Ringmann, in reference to South America. It was applied to both North and South America by Gerardus Mercator in 1538. America derives from the Latin version of Italian explorer Amerigo Vespucci's first name; the feminine form America accorded with the feminine names of Asia and Europa. In modern English and South America are considered separate continents, taken together are called America or the Americas in the plural; when conceived as a unitary continent, the form is the continent of America in the singular. However, without a clarifying context, singular America in English refers to the United States of America. In the English-speaking world, the term America used to refer to a single continent until the 1950s: According to historians Kären Wigen and Martin W. Lewis, While it might seem surprising to find North and South America still joined into a single continent in a book published in the United States in 1937, such a notion remained common until World War II.
By the 1950s, however all American geographers had come to insist that the visually distinct landmasses of North and South America deserved separate designations. This shift did not seem to happen in Romance-speaking countries, where America is still considered a continent encompassing the North America and South America subcontinents, as well as Central America; the first inhabitants migrated into the Americas from Asia. Habitation sites are known in Alaska and the Yukon from at least 20,000 years ago, with suggested ages of up to 40,000 years. Beyond that, the specifics of the Paleo-Indian migration to and throughout the Americas, including the dates and routes traveled, are subject to ongoing research and discussion. Widespread habitation of the Americas occurred during the late glacial maximum, from 16,000 to 13,000 years ago; the traditional theory has been that these early migrants moved into the Beringia land bridge between eastern Siberia and present-day Alaska around 40,000–17,000 years ago, when sea levels were lowered during the Quaternary glaciation.
These people are believed to have followed herds of now-extinct pleistocene megafauna along ice-free corridors that stretched between the Laurentide and Cordilleran ice sheets. Another route proposed is that, either on foot or using primitive boats, they migrated down the Pacific coast to South America. Evidence of the latter would since have been covered by a sea level rise of hundreds of meters following the last ice age. Both routes may have
Claudius Ptolemy was a Greco-Roman mathematician, astronomer and astrologer. He lived in the city of Alexandria in the Roman province of Egypt, wrote in Koine Greek, held Roman citizenship; the 14th-century astronomer Theodore Meliteniotes gave his birthplace as the prominent Greek city Ptolemais Hermiou in the Thebaid. This attestation is quite late, and, according to Gerald Toomer, the translator of his Almagest into English, there is no reason to suppose he lived anywhere other than Alexandria, he died there around AD 168. Ptolemy wrote several scientific treatises, three of which were of importance to Byzantine and Western European science; the first is the astronomical treatise now known as the Almagest, although it was entitled the Mathematical Treatise and known as the Great Treatise. The second is the Geography, a thorough discussion of the geographic knowledge of the Greco-Roman world; the third is the astrological treatise in which he attempted to adapt horoscopic astrology to the Aristotelian natural philosophy of his day.
This is sometimes known as the Apotelesmatika but more known as the Tetrabiblos from the Greek meaning "Four Books" or by the Latin Quadripartitum. Ptolemaeus is a Greek name, it occurs once in Greek mythology, is of Homeric form. It was common among the Macedonian upper class at the time of Alexander the Great, there were several of this name among Alexander's army, one of whom made himself pharaoh in 323 BC: Ptolemy I Soter, the first king of the Ptolemaic Kingdom. All male kings of Hellenistic Egypt, until Egypt became a Roman province in 30 BC ending the Macedonian family's rule, were Ptolemies; the name Claudius is a Roman nomen. It would have suited custom if the first of Ptolemy's family to become a citizen took the nomen from a Roman called Claudius, responsible for granting citizenship. If, as was common, this was the emperor, citizenship would have been granted between AD 41 and 68; the astronomer would have had a praenomen, which remains unknown. The ninth-century Persian astronomer Abu Maʿshar presents Ptolemy as a member of Egypt's royal lineage, stating that the descendants of Alexander's general Ptolemy I, who ruled Egypt, were wise "and included Ptolemy the Wise, who composed the book of the Almagest".
Abu Maʿshar recorded a belief that a different member of this royal line "composed the book on astrology and attributed it to Ptolemy". We can evidence historical confusion on this point from Abu Maʿshar's subsequent remark "It is sometimes said that the learned man who wrote the book of astrology wrote the book of the Almagest; the correct answer is not known." There is little evidence on the subject of Ptolemy's ancestry, apart from what can be drawn from the details of his name. Ptolemy can be shown to have utilized Babylonian astronomical data, he was a Roman citizen, but was ethnically either a Greek or a Hellenized Egyptian. He was known in Arabic sources as "the Upper Egyptian", suggesting he may have had origins in southern Egypt. Arabic astronomers and physicists referred to him by his name in Arabic: بَطْلُمْيوس Baṭlumyus. Ptolemy's Almagest is the only surviving comprehensive ancient treatise on astronomy. Babylonian astronomers had developed arithmetical techniques for calculating astronomical phenomena.
Ptolemy, claimed to have derived his geometrical models from selected astronomical observations by his predecessors spanning more than 800 years, though astronomers have for centuries suspected that his models' parameters were adopted independently of observations. Ptolemy presented his astronomical models in convenient tables, which could be used to compute the future or past position of the planets; the Almagest contains a star catalogue, a version of a catalogue created by Hipparchus. Its list of forty-eight constellations is ancestral to the modern system of constellations, but unlike the modern system they did not cover the whole sky. Across Europe, the Middle East and North Africa in the Medieval period, it was the authoritative text on astronomy, with its author becoming an mythical figure, called Ptolemy, King of Alexandria; the Almagest was preserved, in Arabic manuscripts. Because of its reputation, it was sought and was translated twice into Latin in the 12th century, once in Sicily and again in Spain.
Ptolemy's model, like those of his predecessors, was geocentric and was universally accepted until the appearance of simpler heliocentric models during the scientific revolution. His Planetary Hypotheses went beyond the mathematical model of the Almagest to present a physical realization of the universe as a set of nested spheres, in which he used the epicycles of his planetary model to compute the dimensions of the universe, he estimated the Sun was at an average dis