At a printing-press established in Walther's house by Regiomontanus, Purbach's Theoricae planetarum novae was published in 1472 or 1473; a series of popular calendars issued from it, and in 1474 a volume of Ephemerides calculated by Regiomontanus for thirty-two years (1474-1506), in which the method of "lunar distances," for determining the longitude at sea, was recommended and explained.
In a letter, Del movimento della cometa apparsa it mese di decembre 1664, published in 1665 under the pseudonym Pier Maria Mutoli, he was the first to suggest the idea of a parabolic path; and another of his astronomical works was Theorica mediceorum planetarum ex causis physicis deducta (Florence, 1666), in which he considered the influence of attraction on the satellites of Jupiter.
He wrote An Astronomical Description of the late Comet (1619); Canicularia (1648); and translated Proclus' De Sphaera, and Ptolemy's De Planetarum Hypothesibus (1620).
Purbach's Theoricae Novae Planetarum (1542), and probably got it from Maurolycus.
For the 1753 edition published at Bologna); a defence of Catholic doctrine, entitled Demonstratio critica religionis Catholicae (Augsburg, 1751); a work on indulgences, which has often been criticized by Protestant writers, De Origine, Progressu, V alore, et Fructu Indulgentiorum (Augsburg, 1 73 5) a treatise on mysticism, De Revelationibus et Visionibus, &c. (2 vols., 1744); and the astronomical work Nova philosophiae planetarum et artis criticae systemata (Nuremberg, 1723).
The dissertation by which Hegel qualified for the position of Privatdozent (De orbitis planetarum) was probably chosen under the influence of Schelling's philosophy of nature.
Some of the works, however, with which he has been credited (including the Theoria or Theorica planetarum, and the versions of Avicenna's Canon of Medicine - the basis of the numerous subsequent Latin editions of that well-known work - and of the Almansorius of Abu Bakr Razi) are probably due to a later Gerard, of the 13th century, also called Cremonensis but more precisely de Sabloneta (Sabbionetta).