medical encyclopedias documenting his research. These were used in the Islamic world and Europe until the 19th century. Nicholas Myrepsos (Late 13th century) was a Byzantine physician known chiefly for his compendium on medical science which is still extant. He was at the court of John III Doukas Vatatzes. He compiled and revised Ancient Greek scripts including, but not limited to Galen, as well as writing his own compendium on medical science, named Dynameron. It consists of 48 sections, containing more than 2500 medical formulae, arranged according to their form and object. It remained the principal pharmaceutical code of the Parisian medical faculty until 1651. He is well known for the preparation, Aurea Alexandrina. Theodoric Borgognoni (1205-1296) was an Italian Dominican friar and Bishop of Cervia who promoted the uses of both antiseptics and anaesthetics in surgery. His written work had a deep impact on Henri de Mondeville, who studied under him while living in Italy and later became the court physician for King Philip IV of France. William of Saliceto (1210-1277) was an Italian surgeon of Lombardy who advanced medical knowledge and even challenged the work of the renowned Greco-Roman surgeon Galen (129-216 AD) by arguing that allowing pus to form in wounds was detrimental to the health of the patient. Thomas Aquinas (1227–74), Doctor Angelicus, was an Italian theologian and friar in the Dominican Order. As his mentor Albert the Great, he is a Catholic Saint and Doctor of the Church. In addition to his extensive commentaries on Aristotle's scientific treatises, he was also said to have written an important alchemical treatise titled Aurora Consurgens. However, his most lasting contribution to the scientific development of the period was his role in the incorporation of Aristotelianism into the Scholastic tradition. Arnaldus de Villa Nova (1235-1313) was an alchemist, astrologer, and physician from the Crown of Aragon who translated various Arabic medical texts, including those of Avicenna, and performed optical experiments with camera obscura. Theodoric of Freiberg (c. 1250 – c. 1311) was a natural philosopher and theologian, who wrote highly original treatise on optics, explaining partially, colors and positions of primary and secondary rainbows Pseudo-Geber (fl late 13 century) was an alchemist, who wrote Summa perfectionis magisterii, the most important medieval alchemical treaty. John Duns Scotus (1266–1308), Doctor Subtilis, was a member of the Franciscan Order, philosopher and theologian. Emerging from the academic environment of the University of Oxford.