In 1781, the Imperial Librarian and pioneering print scholar Adam von Bartsch edited aportfolio of thirteen woodcuts associated with Albrecht Dürer, the original blocks for which had been recently rediscovered at Schloss Ambras and the Jesuit College in Graz (Fig. 1).1 Given the rarity of the designs (some of which were thought not to have survived in original impressions), a limited edition was printed, financed by the successful Viennese publisher Joseph Edlen von Kurzböck. At the heart of this miscellaneous collection is a series of four scientific images commissioned between 1512 and 1515 by the humanist Johannes Stabius (1460–1522), best known as coordinator of the monumental prints—each composed of multiple woodblocks, the Arch of Honor (1512–18) and the Triumphal Procession (1507–22) for the Holy Roman Emperor Maximilian I.2 Cut by the master Formschneider Hieronymus Andreae to drawings produced in Dürer’s workshop, these elegant devices were invented by Stabius as gifts for the emperor and his court to use in timetelling and the casting of horoscopes (Fig. 2).3 In their design, dedicatees, date, and makers, they are intimately connected not only to the monumental prints but also to Dürer’s celebrated Star Charts and World Map, the latter included in Bartsch’s portfolio.4 Bartsch, who had seen sixteenth-century