How Did Cartographers Create World Maps before Airplanes and Satellites ? An Introduction

J’ai enfin pris le temps d’y jeter un oeil plus en détails...et je me suis rendu compte qu’il faut retourner la carte pour reprendre ses repères euro-centrés (oui c’est moche 😔) et comprendre à quel point la carte était « précise » (pour l’époque)

J’ai mis un sacré moment à comprendre cette inversion nord-sud ! C’est en finissant par trouver la « mare mediterraneu » que ça a fait tilt ! (bon sang, la botte de l’Italie, mais elle est « à l’envers » !).

Et oui, c’est assez bluffant comme précision, quoi que j’ignore ce que valaient les autres productions de l’époque ou un peu avant. Est-ce qu’il y a un saut qualitatif important avec cette carte ? Je ne saurais dire, n’y connaissant pas grand chose.

😅 je me sens moins seul !
Peut être qu’@odilon ou @visionscarto sauront pour le saut qualitatif ?

Alors en fait la réponse est un peu (beaucoup) sur le même site. Va à l’étape 5, tu va voir une frise chronologique des mappemondes de 700 et quelques jusqu’autours de 1470. Et là tu te dis que ah oui, la carte de Fra Mauro elle a quelques longueurs d’avance.

Et en plus tu vois bien la bascule avant Fra Mauro / après.

C’est vrai qu’il y a une sacrée différence de précision...

A l’exception des cartes catalanes peut être. Enfin je précise, la partie ouest de l’Atlas Catalan de 1375 me parait incroyable précis aussi (pour l’époque) côté occident/Afrique du nord (A partir du moyen jusqu’à l’extrême orient tu voyais que les gars ils y allaient à l’aventure par contre...).

Et la seule où je retrouve ce niveau de précision est le planisphère catalan de 1460...qui est aussi le seul ou je retrouve peut être un peu de Fra Mauro d’ailleurs.

Le reste...m’impressionne beaucoup moins.

explication de l’orientation Sud en haut:

The orientation of the map by Fra Mauro (active ca. 1430-ca. 1459/1464), with the south at the top, may be its most immediately striking and intriguing characteristic to the modern observer, who may find the arrangement confusing. Because we are accustomed to reading maps with the north at the top, it can be difficult at first to make sense of the relations among the land masses. Map orientation is a convention that has undergone numerous changes over the centuries. Most world maps designed between 1150 and 1500, for example, are oriented with the east at the top, both because the sun—associated in Christian cosmology with Christ—rises in the east, and because it was believed that the Garden of Eden was located in that direction.

Still, Christian cosmology also found reason to orient maps toward the south. Eden, the Earthly Paradise, was indeed thought to be in the east, but at an unspecified location somewhere in the Southern Hemisphere, in correspondence to the Heavenly Paradise, which was held to stand at the peak of all the celestial spheres, and thus be rightly positioned at the uppermost part of cosmological diagrams. Among the world maps of Fra Mauro’s time, a Southern orientation is featured in the 1448 world map by Andreas Walsperger, in the so-called “Borgia World Map” produced during the first half of the 15th century, and in the “Zeitz World Map” from the last quarter of that century.

A Southern orientation is also common in Medieval Islamic maps, perhaps in accordance with Aristotle’s description, in De caelo, of the Antarctic Pole as the highest point in the universe. Fra Mauro provides no explanation for the south-up orientation of his map, no doubt presuming to adopt a widely shared convention of using the Sun at its peak—the most prominent astronomical element along with the Pole Star—to precisely determine the direction of the meridian passing through the Earth’s poles.
▻https://mostre.museogalileo.it/framauro/en/historical-context/the-world-map/south-up-orientation.html

on continue ?

►https://www.openculture.com/2022/05/how-did-cartographers-create-world-maps-before-airplanes-and-satellites

▻https://invidious.fdn.fr/latest_version?id=AJBBVQrRwqo&itag=22

Regular readers of Open Culture know a thing or two about maps if they’ve paid attention to our posts on the history of cartography, the evolution of world maps (and why they are all wrong), and the many digital collections of historical maps from all over the world. What does the seven and a half-minute video above bring to this compendium of online cartographic knowledge? A very quick survey of world map history, for one thing, with stops at many of the major historical intersections from Greek antiquity to the creation of the Catalan Atlas, an astonishing mapmaking achievement from 1375.

The upshot is an answer to the very reasonable question, “how were (sometimes) accurate world maps created before air travel or satellites?” The explanation? A lot of history — meaning, a lot of time. Unlike innovations today, which we expect to solve problems near-immediately, the innovations in mapping technology took many centuries and required the work of thousands of travelers, geographers, cartographers, mathematicians, historians, and other scholars who built upon the work that came before. It started with speculation, myth, and pure fantasy, which is what we find in most geographies of the ancient world.

Then came the Greek Anaximander, “the first person to publish a detailed description of the world.” He knew of three continents, Europe, Asia, and Libya (or North Africa). They fit together in a circular Earth, surrounded by a ring of ocean. “Even this,” says Jeremy Shuback, “was an incredible accomplishment, roughed out by who knows how many explorers.” Sandwiched in-between the continents are some known large bodies of water: the Mediterranean, the Black Sea, the Phasis (modern-day Rioni) and Nile Rivers. Eventually Eratosthenes discovered the Earth was spherical, but maps of a flat Earth persisted. Greek and Roman geographers consistently improved their world maps over succeeding centuries as conquerers expanded the boundaries of their empires.

Some key moments in mapping history involve the 2nd century AD geographer and mathematician Marines of Tyre, who pioneered “equirectangular projection and invented latitude and longitude lines and mathematical geography.” This paved the way for Claudius Ptolemy’s hugely influential Geographia and the Ptolemaic maps that would eventually follow. Later Islamic cartographers “fact checked” Ptolemy, and reversed his preference for orienting North at the top in their own mappa mundi. The video quotes historian of science Sonja Brenthes in noting how Muhammad al-Idrisi’s 1154 map “served as a major tool for Italian, Dutch, and French mapmakers from the sixteenth century to the mid-eighteenth century.”

▻https://invidious.fdn.fr/latest_version?id=wIIcsSMQp7Q&itag=22

The invention of the compass was another leap forward in mapping technology, and rendered previous maps obsolete for navigation. Thus cartographers created the portolan, a nautical map mounted horizontally and meant to be viewed from any angle, with wind rose lines extending outward from a center hub. These developments bring us back to the Catalan Atlas, its extraordinary accuracy, for its time, and its extraordinary level of geographical detail: an artifact that has been called “the most complete picture of geographical knowledge as it stood in the later Middle Ages.”

Created for Charles V of France as both a portolan and mappa mundi, its contours and points of reference were not only compiled from centuries of geographic knowledge, but also from knowledge spread around the world from the diasporic Jewish community to which the creators of the Atlas belonged. The map was most likely made by Abraham Cresques and his son Jahuda, members of the highly respected Majorcan Cartographic School, who worked under the patronage of the Portuguese. During this period (before massacres and forced conversions devastated the Jewish community of Majorca in 1391), Jewish doctors, scholars, and scribes bridged the Christian and Islamic worlds and formed networks that disseminated information through both.

In its depiction of North Africa, for example, the Catalan Atlas shows images and descriptions of Malian ruler Mansa Musa, the Berber people, and specific cities and oases rather than the usual dragons and monsters found in other Medieval European maps — despite the cartographers’ use of the works like the Travels of John Mandeville, which contains no shortage of bizarre fiction about the region. While it might seem miraculous that humans could create increasingly accurate views of the Earth from above without flight, they did so over centuries of trial and error (and thousands of lost ships), building on the work of countless others, correcting the mistakes of the past with superior measurements, and crowdsourcing as much knowledge as they could.

►https://www.openculture.com/2022/05/how-did-cartographers-create-world-maps-before-airplanes-and-satellites

avec en prime :

un site décrivant en détail le fameux Atlas Catalan :
▻https://www.cresquesproject.net/catalan-atlas-legends

Une description scientifique de 80 pages de ce même Atlas :
▻http://www.myoldmaps.com/late-medieval-maps-1300/235-catalan-atlas/235-catalan-atlas.pdf

et...un site amateur d’un passionné comme je les affectionne beaucoup :
▻http://www.myoldmaps.com

un nouveau site qui présente une collection de cartes antiques :

▻https://oculi-mundi.com

Il est très joli.e