Copernicus’ library constitutes a very important testimony to his education and interests, but unfortunately, most of the books he owned have been either dispersed or destroyed.
Single volumes must have been passed on to Copernicus’ relatives and friends, whereas the lion’s share of the collection went to the cathedral chapter library in Frombork (Frauenburg) where it shared the fate of other Warmian collections taken away to Sweden by the troops of King Gustavus Adolfus and Charles XII in the 17th c. and the early 18th c.
Part was handed over to the University Library in Uppsala, some more valuable items went to the Royal Library in Stockholm, while others were kept by military officials and commanders. It is not certain how many books from Copernicus’ library have been auctioned and how many destroyed. The practice of the intentional or careless removal of the provenance markings of former owners caused further damage. More irreparable losses occurred when the Uppsala library decided to separate books formerly jointly bound (the former ‘block books’), and to bind specific titles separately. At present only eleven volumes have distinct provenance to Copernicus. Others were identified exclusively by knowledge of the unique features that characterised his handwriting and by the marginal notes left by the astronomer.
In 1853 a distinguished Copernican researcher, Leopold Prowe (1821–87), found eight ‘blocks’ containing fifteen books belonging to the Frombork astronomer. Six other Copernican ‘blocks’ (10 titles bound together) were later (in 1875) identified by Maximilian Curtze (1837–1903). At the beginning of the 20th c. a Kraków Copernican scholar, Ludwik Antoni Birkenmajer (1855–1929), ascribed as many as 90 books bound in 48 ‘blocks’ to Copernicus while in 1971 Leonard Jarzębowki identified 49 ‘blocks’ comprising 81 books. German researchers were much more careful, for example Ernst Zinner (1943) narrowed down the number of books formerly belonging to Copernicus’ library to 40 only and Bernhard-Maria Rosenberg (1972) to 44. Paweł Czartoryski was even more prudent, ascribing only 32 books bound in 18 ‘blocks’ in 1978, but quite recently another 11 were identified, however.
It seems that Copernicus started buying books in Kraków after he had enrolled in the Jagiellonian University there and then continued to stock his private library while in Italy. The titles reflect his special interests in mathematics, astronomy, medicine and law. While in Kraków Copernicus purchased four incunabula which he then bound in two ‘blocks’: a first edition of Euclid’s Elementa geometriae (1482); Albohazen Haly’s work on astronomy In iudiciis astrorum (1485); Alfonso X’s Tabula astronomicae (1490); and Tabulae directionum et profectionum (1490) by the distinguished German astronomer Regiomontanus (Johannes Müller).
Copernicus appended a sixteen-leaf notebook to the latter work with with his own notes on mathematics and astronomy made at the turn of 1495 known as the Uppsala Raptularium. While in Italy Copernicus bought Regiomontanus’ Epitoma in Almagestum Ptolemei (1496) and the Greek poem by Aratus of Soli Phenomena (1499) regarded as a great source of knowledge about astronomy in the Middle Ages. His copy of the third edition of Ptolemy’s Cosmography (1486) which discusses the principles of map-making also comes from the period of Copernicus’ studies in Italy. In Bologna Copernicus purchased compilations of Roman Law (ius civile): Digestum vetus (1486), Digestum novum (1489), Institutiones (1490), and a digest of new statutes, Novellae (1494). He also took interest in the deliberations of the distinguished Italian jurist, Baldus de Ubaldis, on civil law (Lectura super I–IX Codicis, 1490), on the feudal law of mediaeval Europe Super usibus feudorum (1500), and on canon law (ius canonici) as well. None has been traced however. In Padua Copernicus purchased at least five medical treatises written by Hugo Senensis (Super quarta Fen primi Canonis Avicennae, 1485), Joannes Michael Savonarola (Practica medicinae, 1486), Valescus de Tarenta (Practica siue Philonium, 1490), Matthaeus Silvaticus (Liber pandectarum medicinae, 1498) and Petri de Argelatta (Chirurgia magistri, 1499). Among other books acquired in his Italian period were a theology handbook Sententiarum libri IV (ca 1491) by Pierre Lombard, and the Greek-Latin dictionary Dictionarum graecum cum interpretatione latina of Joannes Crastonus from 1499–1500.
He continued purchasing books during his stay in Warmia some of which he used for his medical practice including a ‘block’ comprising Breviarium practica medicinae (ca 1485) by Arnold de Villa Nova, Canonica de febribus (1487) by Joannes Michael Savonarola, and Consilia (1514) by Bartholomew Montagnana the Elder. It is difficult to determine exactly when he bought Pliny the Elder’s Historia naturalis (1487), Ptolemy’s Almagest (1515) or Johannes Stoeffler’s Calendarium Romanum magnum (1515), however in the spring of 1524 Bernard Wapowski presented him with a small work on astronomy written by Johannes Werner of Nuremburg entitled De motu octavae sphaerae which, incidentally, Copernicus harshly criticized shortly afterwards.
Copernicus also made use of books belonging to Hildebrand Ferber, a patrician who, when a rebellion broke out in Gdańsk in 1526, left his hometown and found refuge in Lidzbark at the court of his brother Maurice Ferber, Bishop of Warmia. It is quite likely that it was on Hildebrand’s death that Copernicus acquired Regiomontanus’s Calendarium (1492) and the Almanac (1499) of Johannes Stoeffler and Jakob Pflaum. When Georg Joachim Rheticus came to visit the astronomer in Warmia he brought five books which were left in Copernicus’ own library including two Greek editions printed in Basel of Euclid’s Eukleidu Stoicheion (1533) and Ptolemy’s Magne Constructionis (1538). Rheticus also presented his mentor with Witelon’s Perspectiva (1535), Regiomontanus’ De triangulis omnimodis (1533) and Peter Apian’s Instrumentum primi mobilis (1534) from Nuremburg, with an appended treatise – De astronomia libri IX by Gebri filii Affla.
Copernicus must have possessed works by Rheticus himself and also by his fellow canons and friends, including the anti-Lutheran piece, Anthelogikon, written by Tiedemann Giese. None have been recovered and the surviving library items constitute only a small part of the formerly rich collection estimated at around 100–150 volumes.
Most of those that survive bear visible traces of intensive reading and his notes testify to the fact that he often returned to books he had studied before. A closer study of the content of the marginalia left on many pages gives their reader an insight into the way his erudite mind worked and how he gradually arrived at his conclusions.