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The curious astronomer

The astronomer Conrad Heingarter who gathered the various works (texts and tables) in this book clearly was a curious person who had more in mind than just immediate application of astronomical knowledge in his activity as a teacher, physician and astrologer. He included in this collection two of the classical texts about the use of planetary motion tables: the canons by John of Lignères and the canons by John of Saxony, both among the founding fathers of the Parisian Alfonsine tradition. The book includes many other classical texts, one about the astrolabe, attributed to Masha'allah (exemple here), others about eclipse calculation, and also topics that predate the Alfonsine period, too. The work that opens the collection is the classical Teorica planetarum by Johannes Campanus of the 13th century that offers some theoretical grounding of some aspects of the astronomical tables. The collection ends with an intriguing text explaining the way a more ancient astronomical table set worked, the Toledan Tables, from the Arabic tradition in al-Andalus. The inclusion of this work, beginning with the phrase “Arabes maxime”, copied in Heingarter’s hand highlights the astronomer’s interest also in the historical study of astronomy.