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The Constellations and Asterisms of Petrus Apianus (1524–1536)

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The Constellations and Asterisms of Petrus Apianus (1524–1536) Appendix A The Constellations and Asterisms of Petrus Apianus (1524–1536) Petrus Apianus (Fig. A.1), also known as Peter Apian, Peter Bennewitz, and Peter Bienewitz, was one of the foremost mathematical publishers, instrument makers and cartographers of the sixteenth century. Born on 16 April 1495 in Leisnig, Saxony, he was one of four sons of Martin Bienewitz, a shoemaker of comfortable middle-class extraction. He was educated first at the Latin school in Rochlitz, and then from 1516 to 1519 at the University of Leipzig where he studied astronomy, mathematics, and cosmography. While at Leipzig, he Latinized his surname to “Apianus”, deriving from apis (“bee”) and equivalent to Biene in German. Apianus relocated to Vienna in 1519 to complete his degree at the University of Vienna, taking a B.A. 2 years later during an outbreak of plague. Fleeing the city, he landed first in Regensburg before settling in Landshut. He married Katharina Mosner, the daughter of a local councilman, in 1526 and by her had fourteen children. Among his sons was Philip Apianus, born 1531, who would later follow his father into the study of mathematics. Apianus was fascinated first and foremost by cosmography, a broad science of the Renaissance which set out to explain everything in the universe within a mathematical framework. He excelled in its study and later became one of its most famous practitioners; by modern standards, he can be thought of as one of the best applied mathematicians of his day. His interest in cartography was stimulated during one of the most momentous periods in European history: the Age of Exploration, witnessing the trailblazing voyages of the likes of da Gama, Columbus, and Magellan. His first published work was a world map, Typus orbis universalis (1520), itself based on a contemporary map drawn by the German cartographer Martin Waldseemüller.1 The following year, Apianus published Isagoge, a geographical commentary on the 1520 map. The work that firmly established Apianus’ academic credentials was Cos- mographicus Liber, published at Landshut in 1524. Frequently known as the 1Waldseemüller (1470–1522) is traditionally credited with the first recorded usage of the word “America” in honor of the Florentine explorer Amerigo Vespucci. © Springer International Publishing Switzerland 2016 147 J.C. Barentine, Uncharted Constellations, Springer Praxis Books, DOI 10.1007/978-3-319-27619-9 148 A The Constellations and Asterisms of Petrus Apianus (1524–1536) Fig. A.1 A portrait of Petrus Apianus in an engraving by the Dutch publisher Philip Galle (1537–1612), c. 1570 Cosmographia in later editions, it was a lavishly-illustrated treatise on astronomy, navigation, geography, cartography and weather; it contained digressions on various map projections, the shape of the Earth, and descriptions of the use of mathematical instruments. While the book would later appear in dozens of editions in four languages across Europe, it was not at first a runaway hit. However, a 1533 edition edited and expanded by Gemma Frisius (born Jemme Reinerszoon, 1508–1555), a renowned Dutch physician and cartographer who was later a tutor to Gerardus Mercator, became a bestseller. Frisius had good cause to lend his name and effort to the revision, as his workshop produced the very instruments that Apianus described and illustrated. The Cosmographia attracted the attention of the Holy Roman Emperor Charles V (1500–1558), who praised the work at the Imperial Diet of 1530 and issued printing monopolies to Apianus’ press in 1532 and 1534. In 1535, Charles granted Apianus the right to display a coat of arms. On the basis of the Cosmographia, Apianus was appointed Professor of Mathe- matics at the University of Ingolstadt in 1527, a post he held for the remainder of his life despite later appeals from universities at Leipzig, Padua, Tübingen, and Vienna. In addition to his work at the university, Apianus operated a printshop at Ingolstadt where he gained a reputation for producing high-quality editions of various texts on cartography and geography. He printed his own works on the press as well. In 1533 he published Horoscopion Apiani Generale . , a description of the ‘horoscopion,’ a device used to solve various astronomical measurement problems (Fig. A.2). His A The Constellations and Asterisms of Petrus Apianus (1524–1536) 149 Fig. A.2 The title page from Petrus Apianus’ Horoscopion Apiani generale . (1533) showing the eponymous device 150 A The Constellations and Asterisms of Petrus Apianus (1524–1536) Instrumentum sinuum sive primi (1534) was a mathematical text that included the first sine tables calculated to every whole minute of arc, which he applied to a variety of problems in astronomy, navigation and architecture. In the same year, he published the first large-scale map of Europe, no known copies of which survive. He printed a single-sheet map, Imagines syderum coelestium . ,in1536, which showed the 48 Ptolematic constellations (less Serpens) and introduced new figures Rosa and Phaeton. Apianus’ magnum opus, Astronomicum Caesareum (“The Emperor’s Astron- omy”), followed in 1540. Dedicated to Charles V, it includes a number of then-new scientific ideas such as a method of computing longitude via observations of solar eclipses and the first published assertion that the tails of comets always point away from the direction of the Sun. Astronomicum Caesareum also introduced a technological innovation in publishing: the volvelle, or wheel chart (Fig. A.3). First developed by Islamic astronomers in the Medieval period, volvelles are paper constructions printed with various dials and numerical indicators that function as simple analog computers. Apianus developed volvelles into functional works of high art, showing examples of their use in the book to calculate the dates of historical eclipses of the Sun and Moon. Charles was delighted by his “Astronomy,” appointing Apianus the court mathe- matician and knighting the four brothers Bienewitz. He promised Apianus the sum of 3,000 guilders and in 1544 named him an Imperial Count Palatine, bestowing on him the right to legally legitimize children and grant degrees of higher learning. The royal attention served to further Apianus’ reputation as one of the most preeminent scientists of his time. Even as he tended to neglect his teaching duties at the university, Apianus remained involved in the development of new astronomical and surveying instruments, including his own designs for quadrants and armillary spheres. He died at Ingolstadt on 21 April 1552, succeeded in his post by his son, Philip. Petrus Apianus introduced two new constellations, neither of which survived beyond the end of the seventeenth century: • Phaeton (the son of Apollo-Helios) • Rosa (the Rose) Apianus also provided the earliest known European description of some indige- nous constellations of Arabia: • Filiae Ursae Majoris (the Daughters of the Great Bear) • Pastor Canes et Oves (the Shepherd, the Dog and Sheep) • Duae Alae (the Two Wings) • Quinque Dromedarii (the Five Dromedaries) The figures Apianus drew occupy a unique place between handy asterisms, a recounting of indigenous folklore, and actual innovation. A The Constellations and Asterisms of Petrus Apianus (1524–1536) 151 Fig. A.3 A volvelle from Astronomicum Caesareum (1540) showing the conversion between celestial declination and horizon altitude coordinates. An outer wheel labeled “horizon” is rotated and the declination corresponding to the observer’s zenith is read from the pointer above the human figure. The Latin title reads “These may be clearly seen from the instrument” Asterism from Cosmographicus Liber (1524) Apianus’ first major popular work, Cosmographicus Liber, was published by the printer and priest Johann Weyssenburger at Landshut in 1524. It was an immediate success enjoying at least 45 editions in four languages by at least 18 different publishers and remained in print for over a half-century after Apianus’ death. Gemma Frisius (1508–1555) carried out a careful correction and annotation of the 1524 version; the result was published in 1529 as a second edition, entitled Cosmographia von Petrus Apianus. Two years later, a less expensive, abridged version of Apianus’ original called Cosmographiae introductio was published at Ingolstadt. But it was the 1533 edition of Frisius’ annotated version, including his short works De locorum describendorum ratione (Concerning the method of describing places) and De eorum distantijs inueniendis (On the determination of distances), that earned the book its greatest popularity and secured its place in history. 152 A The Constellations and Asterisms of Petrus Apianus (1524–1536) However, some of Apianus’ success was merely the result of fortuitous timing: a European reading public with an appetite for all things related to the New World ate up the book’s detailed discussion of newly-discovered lands in America. Again, he seems to have merely recycled content from previous authors; his information appears to be substantially drawn from the accounts in Cosmographiae introductio by Martin Waldseemüller, published at St. Die in 1507, and Johann Schöner’s Luculentissima quaeda[m] terrae totius descriptio (The most brilliant description of the entire Earth), printed in 1515 at Nuremburg. Apianus’ work so strongly resembles Schöner’s book that Cosmographicus Liber may simply be an abridgment of its text. Cosmographicus Liber was a treatise on astronomy and navigation, but more broadly it was aimed at an educated lay audience as a kind of “popular science” of the day. The content was largely appropriated directly from Ptolemy, but it is the book’s volvelles that represent its main selling point and principal innovation. Whereas earlier books of similar content were largely constructed around sets of tabular information, Apianus’ volvelles turned the pages of Cosmographicus Liber into functional computers, enabling skilled users to make calculations involving navigation, distances and time. Apianus introduced one new figure in Cosmographicus Liber, an alternate figure for the bright stars of Ursa Major he called “Plaustrum” (Fig. A.4).
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