cosmographic

Claudius Ptolemy, Cosmographia, The inhabited world on the earth sphere, 1465-1470. Manuscript on parchment. Florence. © Bibliothèque Nationale de France

In the 2nd century AD, the totality of Greek knowledge was summed up by Ptolemy, the Greek astronomer and geographer. In his system, the earth is round and at the centre of the universe. Only one quarter, the ecumene, is inhabited, isolated by an impassable ocean.

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General Atlas of All the Islands in the World

Islario general de todas las islas del mundo (General atlas of all the islands in the world) is the greatest work by Seville cosmographer Alonso de Santa Cruz (1505–67). The atlas was begun during the reign of Holy Roman Emperor and King of Spain Charles V and finished in that of his son King Philip II, to whom it was dedicated. It consists of 111 maps representing all the islands and peninsulas of the world, and showing all the discoveries made by European explorers from 1400 to the mid-16th century. The atlas begins with a letter by Santa Cruz to the king, in which he justifies his work and explains different geographic concepts. Preceding the maps is “Breve introducción de la Sphera” in which Santa Cruz makes a cosmographic description, illustrated by 14 astronomical figures. The maps are organized in four parts: the first deals with the North Atlantic; the second, with the Mediterranean and adjacent areas; the third, with Africa and the Indian Ocean; and the fourth with the New World. The maps include scales in latitude and some in longitude and bodies of water with varied scales and oriented with compass roses. The Islario general is the earliest atlas in which paper is used, instead of the parchment that was previously most commonly used for such charts. The design of the maps is more functional, with less attention to aesthetics and more to geographic detail than in the late-medieval portolan maps and atlases. Scholars have determined, on the basis of the dates that appear in the descriptive texts on the islands, that the maps were made beginning in the fourth decade of the 16th century, around 1539, and that the entire atlas was completed circa 1560. It is highly probable that the Islario general was a part of a Geografía Universal that Santa Cruz never finished. Santa Cruz was one of the key figures of the Casa de Contratación (House of Trade) in Seville. One of his first works was a set of the spherical charts of the New World. He created various other works on cosmography and geography, such as the Libro de longitudes; and on historical themes, including  Crónica de los Reyes Católicos (Chronicle of the Catholic kings) and Crónica de Carlos V (Chronicle of Charles V). Following Santa Cruz’s death, his successor, Andrés García de Céspedes, attempted to claim credit for this work. On the cover the name Alonso de Santa Cruz has been erased, García de Céspedes’s name is inserted as if he were the author, and the work is dedicated to King Philip III. In the manuscript itself, apocryphal texts have been superimposed over the originals, with the aim of disguising the real authorship and date of creation.

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Images from an illustrated version of a 13th-century Arabic treatise by Zakariya al-Qazwini titled ‘Ajā’ib al-makhlūqāt wa-gharā’ib al-mawjūdāt (Marvels of Things Created and Miraculous Aspects of Things Existing). The text is probably the best known example of ‘ajā’ib or ‘jā’ib al-makhlūqāt literature, a genre of classical Islamic literature that was concerned with “mirabilia”: cosmographical and geographical topics that challenged understanding. Al-Qazwini’s treatise explored an eclectic mix of topics, from humans and their anatomy to strange mythical creatures; from plants and animals to constellations of stars and zodiacal signs. The treatise was extremely popular and was frequently illustrated over the centuries into both Persian and Turkish. The images featured here are from an exquisitely illustrated Persian translation, thought to hail from 17th-century Mughal India. For more info see the note on the US National Library of Medicine website.

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Fernando Vaz Dourado: Atlas, 1576

This atlas has been attributed to the important Portuguese cartographer, navigator, and illuminator Fernão Vaz Dourado (circa 1520−80), based on similarities between other maps by Vaz and illustrations in this manuscript. Vaz spent his last years in Portuguese Goa (present-day India) and is known to have produced seven brilliantly illuminated sea atlases between 1568 and 1580. His portolan charts belong to a class of late-16th-century cartographic masterpieces, which reflect the period’s rising demand for cartographic works that were both visually impressive and accurate for practical navigation. This atlas, dating from about 1576, consists of 17 illuminated maps, in addition to declination tables and cosmographic rules.

Johannes Kepler - Platonic Solid Model of the Solar System, “Mysterium Cosmographicum” (The Cosmographic Mystery), 1600.

Kepler’s Cosmological theory, based on the Copernican system, states that five Pythagorean regular Polyhedra dictate the structure of the Universe and reflect God’s plan through Geometry. This was the first attempt since Copernicus to say that the theory of Heliocentrism is physically true.

Kepler claimed to have had an epiphany on July 19, 1595, demonstrating the periodic conjunction of Saturn and Jupiter in the Zodiac: he realized that regular Polygons bound one inscribed and one circumscribed Circle at definite Ratios, which might be the Geometrical basis of the Universe. After failing to find a unique arrangement of Polygons that fit known Astronomical observations, Kepler began experimenting with 3-dimensional Polyhedra. He found that each of the five Platonic Solids could be uniquely inscribed and circumscribed by Spherical Orbs; nesting these Solids, each encased in a Sphere, within one another would produce six layers, corresponding to the six known Planets - Mercury, Venus, Earth, Mars, Jupiter, and Saturn. By ordering the Solids correctly - Octahedron, Icosahedron, Dodecahedron, Tetrahedron, Cube - Kepler found that the Spheres could be placed at intervals corresponding to the relative sizes of each Planet’s path, assuming the Planets circle the Sun. Kepler also found a formula relating the size of each Planet’s orb to the length of its orbital period: from inner to outer Planets, the ratio of increase in orbital period is twice the difference in orb radius.