John of Gmunden was admitted to the baccalaureate examination on October 13, 1402. If he was the astronomer who was accepted as a master into the Faculty of Arts on March 21, 1406, along with eight other candidates, then he spent all his student years at Vienna.
John of Gmunden was admitted to the baccalaureate examination on October 13, 1402. If he was the astronomer who was accepted as a master into the Faculty of Arts on March 21, 1406, along with eight other candidates, then he spent all his student years at Vienna.
John of Gmunden was an Austrian mathematician, astronomer, and inventor who compiled voluminous astronomical tables. He also studied Euclid's Elements and John Holywood's Sphaera materialis.
Background
John of Gmunden was born c. 1380-1384 in Gmunden am Traunsee (Gmunden), Austria. His origins were long the subject of disagreement. Gmunden am Traunsee, Gmünd in Lower Austria, and Schwäbisch Gmünd were all thought to be possible birthplaces; and Nider, Schindel, Wissbier, and Krafft possible family names. But the research in the records of the Faculty of Arts of the University of Vienna, however, appears to have settled the question. The Vienna matriculation register records the entrance, on October 13, 1400, of an Austrian named “Johannes Sartoris de Gmundin,” that is, of the son of a tailor from Gmunden.
Education
John of Gmunden was admitted to the baccalaureate examination on October 13, 1402. If he was the astronomer who was accepted as a master into the Faculty of Arts on March 21, 1406, along with eight other candidates, then he spent all his student years at Vienna. His teacher was Nicolaus of Dinkelsbühl.
John of Gmunden’s career can be divided into four periods. In the first (1406-1416) his early lectures - besides one given in 1406 on Theorice - were devoted to non-mathematical subjects: Physica, Metheora, Tractatus Petri Hyspani, and Vetus ars. On August 25, 1409, he became magister stipemliatus and received an appointment at the Collegium Ducale. He gave his first mathematics lecture in 1412. He was also interested in theology, the study of which he completed in 1415 as Baccalaureus biblicus formatus in theologia. Two lectures in this field concerned the Exodus and the theology of Peter Lombard.
In 1416-1425 John of Gmunden lectured exclusively on mathematics and astronomy, which led to the first professorship in these fields at the University of Vienna; the position became permanent under Maximilian I. His mathematics lectures were entitled Algorismus de minutiis, Perspectiva, Algorismus de integris, and Elementa Euclidis. In this series, one does not find a lecture on latitudines formarum, which was already part of the curriculum. His astronomy lectures were entitled Theoricae planetarum, Sphaera meterialis, and De astrolabio. When John became ill in 1418, he lost his salary, since only someone actively teaching could be paid; but, at the request of the faculty, the duke removed this hardship. John obtained permission to hold lectures in his own house - a rarely granted privilege. During his years at the university he held many honorary offices. He was dean twice (1413 and 1423) and examiner of Saxon (1407), Hungarian (1411), and Austrian (1413) students. In 1410 he was named publicus notarius. In 1414 he was a receiver of the faculty treasury and member of the dormitory committee for the bylaws for the burse. In 1416 he was Conciliarius of the Austrian nation, and from 1423 to 1425 he was entrusted with supervising the university’s new building program.
The third period (1425-1431) began when John of Gmunden retired from the Collegium Ducale and, on May 14, 1425, became a canon of the chapter of St. Stephen. Previously he had been ordained priest (1417) and delivered sermons. He was also vice-chancellor of the university, which had long been closely associated with St. Stephen’s Gymnasium. Henceforth John devoted himself to writings on astronomy, astronomical tables, and works on astronomical instruments. He also lectured on the astrolabe.
In the last period (1431-1442) John became plebanus in Laa an der Thaya, an ecclesiastical post that yielded an income of 140 guldens. In 1435 he wrote his will, in which he bequeathed his books and instruments to the library of the Faculty of Arts. He also gave precise instructions for their use. We note the absence from his list of those books on which his own works were based, but these undoubtedly were in the Faculty of Arts library.
The great number of extant manuscripts of John of Gmunden’s works attests to his extensive literary activity, which began in 1415 and steadily intensified until his death. Many of the manuscripts are in his own hand, such as those in Codex Vindobonensis 2440, 5151, 5144, and 5268. Most of those done by students and other scribes dates from the fifteenth century. Only a small portion are from a later period. This indicates that his works were superseded by those of peurbach and Regiomontanus. John’s writings can be divided into tables, calendars, and works on astronomical instruments.
John of Gmunden produced five versions of his tabular works, which contained tables of the motions of the sun, the moon, and the planets, as well as of eclipses and new and full moons. They also included explanatory comments (tabulae cum canonibus). They are all enumerated in his deed of gift. Regiomontanus studied the first of the tabular works and found an error in it that he noted in the margin. John was also the author of many individual writings on astronomy that were not made part of the tabular works. Shorter than the latter, they contained tables of planetary and lunar motions, of the true latitudes of the planets, and of the true new and full moons, as well as tables of eclipses. Further astronomical writings can be found in his works on astronomical instruments.
Along with elaborating and improving the values of his tables, John of Gmunden was especially concerned with the preparation of calendars, which provided in a more usable form the information contained in the tabular works. In addition to such astronomical data, they included the calendar of the first year of a cycle with saints’ days and feast days, dominical letter, and the golden numbers, so that the calendar could be used during all nineteen years of a cycle. He brought out four editions of the calendar: the first covered 1415-1434; the second, 1421-1439; the third, 1425-1443; and the fourth, 1439-1514. The fourth edition was printed on Gutenberg’s press in 1448. Two other calendars bearing John’s name were published later. From one of them, a xylographic work, there remains only a woodblock; of the other, a peasants’ calendar, only a single copy is extant.
John of Gmunden’s third area of interest was astronomical instruments; he explained how they operated and gave directions for making them. In his deed of a gift he mentioned two works in this field: a volume bound in red parchment containing Astrolabium Alphonsi and a little book written by himself, entitled Astrolabii quadrantes. In his will, he lists the following instruments: a celestial globe, an equatorium of Campanus with models taken from the Albion, an astrolabe, two quadrants, a spherea materialis, a large cylindrical sundial, and four theorice lignee. Of all this apparatus nothing remains in Vienna.
Among his students, Tannstetter mentions especially Georg Pruner of Ruspach. His co-workers included Johann Schindel, loannes Feldner, and Georg Mustinger, prior of the Augustinian monastery in Klosterneuburg. He also greatly influenced Peurbach. To be sure, the latter cannot be considered a direct student of John’s since Peurbach was nineteen when John died. Nevertheless, he undoubtedly knew John personally, and he studied his writings thoroughly. The same is known of Regiomontanus, who in his student years at Vienna made critical observations in copies of John’s works.78 He also bought a copy of the treatise on the albion.
Achievements
Religion
John of Gmunden was affiliated with the Roman Catholic church, and took an active part in religious activity in Vienna.
Views
John of Gmunden’s work reflects the goal of the instruction given in the Scholastic universities: to teach science from existing books, not to advance it. He was above all a teacher and an author.
His main concerns lay in astronomy, and thus even in his mathematical writings, he treated only questions of use to astronomers. Tannstetter cites three mathematical treatises by him: an arithmetic book with sexagesimal fractions, a collection of tables of proportions, and a treatise on the sine. Only the first of these were printed, appearing in a compendium containing a series of writings that provided the basis for mathematics lectures. In this area, John introduced no innovations.
John of Gmunden’s work in astronomy was of greater importance than his efforts in mathematics. He probably did not himself make any systematic observations of the heavens, but his students are known to have done so. The instruments that he had constructed according to his own designs were used only in teaching and to determine time. He was no astrologer, as can be seen from a letter of September 1432 to the prior Jacob de Clusa, who had made predictions on the basis of planetary conjunctions. Although his library contained numerous astrological writings, the stringent directions in his will pertaining to the lending of these dangerous works show what he thought of this pseudoscience. If occasionally he spoke of the properties of the zodiac signs and of bloodletting, it was because these subjects were of particular interest to purchasers of almanacs.