The present compilation of medieval astronomical knowledge derived from the classical works of Persian and Arabic astrologers such as Abu Ma’shar (Albumasar), Meshallah (Messahalla), and others. The work is divided into ten treatises dealing with the Zodiac, the planetary system, meteorology, and theology.
We know next to nothing about the author. The name on the title, Leupoldi ducatus Austrie filii, was often misinterpreted as Duke of Austria, but it simply means ‘born in the duchy of Austria’. Leopold does not take credit for the work, explaining that he does not to seek the title of the author as there were more than one: "Nomen autoris non querat. Non enim unus autor sed plurimi…" He adds that his role was only being a "fidelis…" (observer) and "diligens" (compiler).
The edition at hand is an early book, effectively illustrated with scientific diagrams, constellations, figures of ancient gods, and symbols of the zodiac. The large, astronomical woodcuts of the seven planets in their chariots and the signs of the zodiac comprise the famous series that the publisher Ratdolt used several times before for other projects. His woodcuts are among the earliest known, printed figures of constellations.
The fine, astronomical woodcuts are formed in outline, without background or border, and with very little shading. The contours define the images and parallel lines are used to model the forms of the figures. This technique offers simple but clear representations, resulting in light, narrative images created with a minimum of embellishment. The clarity of the figures and the creative manner in which they are presented suggest that the designer and the woodcutters were skilled craftsmen.
The present book opens with the beautiful image of the Sphaera Mundi. The book's smaller woodcut series, again with planets and signs of the zodiac, was newly created in Augsburg. The artist is called the ‘Master of the Hungarian Chronicle’, named after Ratdolt’s 1488 edition of Johannes Thurocz’s Chronica Hungarorum (also available at Dr. Jörn Günther Rare Books), which includes a quite lively series of woodcuts. The woodcuts attributed to him seem to derive from medieval manuscript sources, depicting figures in medieval European costume in a soft modelling style.