GEROLAMO CARDANO

Two influential works by the Italian polymath Gerolamo Cardano (1501-1576) in a beautifully decorated contemporary binding by the German bookbinder Meister des Kolumbaquartiers (Schunke 1937, 336; Einbanddatenbank 129874b), based in .Cologne.

Expert in mathematics, biology, physics, astronomy, astrology and author of more than 200 works on medicine, Cardano is today most known for introducing the use of negative numbers in Europe for the first time (Ars Magna, 1545). The first edition of De Astrorum Iudicii represents one of his most controversial works on astronomy and astrology. Structured as a four-part commentary on the Tetrabiblos (in Latin translation) by the Greek philosopher and mathematician Ptolemy (100-170 AD), the book presents a series of astrological techniques aimed at demonstrating that all the main events in people s lives can be attributed to the stars. In addition, the brief related volume Geniturarum Exempla contains twelve horoscope examples illustrated with attractive diagrams and symbols, among them the horoscope of King Edward VI and of the Archbishop John Hamilton of St. Andrews (Genitura I and II). To these eminent personalities, Cardano predicts a bright future; however, it appears that the latter was hanged by the reformers, while the former died of tuberculosis not long after the publication of this work. The author goes as far as casting the horoscope of Christ: accused of heresy by the Inquisition for these pages, Cardano was imprisoned in 1570.

De Subtilitate Libri XXI is widely considered Cardano s masterpiece and, due to its enormous success, it continued to be reprinted long after the author s death. It is an encyclopaedia of natural science and metaphysics, divided into twenty-one books which respectively deal with: 1) matter and its natural motion, 2) the elements, 3) the sky, 4) light, 5) mixtures and compounds, 6) metals, 7) stones, 8) plants, 9-10) animals, 11-12) humans, their appearance and temperament, 13) the senses, 14) soul and intellect, 15) de incerti generis aut inutilibus subtilitatibus , 16) Sciences, 17) Arts, 18) Miracles, 19) Demons, 20) Angels, 21) God and the universe. This edition constitutes Cardano s update to the first of 1550, and it accounts for more recent geographical discoveries and philosophical discourses. Among the detailed woodcut illustrations, the ones representing machines are perhaps the most fascinating: these include a suction pump, .the .Archimedean screw, a hoist, and many others. In the pages discussing engineering, Cardano also informs us that Leonardo da Vinci tried to fly, but he failed. In the section regarding the sky (Liber III) the author describes the stars observed by Amerigo Vespucci during his third voyage to the Indies.