Albrecht Dürer mapped the stars of the northern and southern hemispheres and printed the first printed star charts, which had been ordered by Johann Stabius in Nürnberg. Around 1515, he was also the first to publish a perspective reproduction of the terrestrial globe, the “Stabiussche Weltkarte.” Perhaps most famously, the main part of the work of ethnic German Nicolaus Copernicus was published in Nürnberg in 1543. But the city was the center of science even before then, and teemed with people of great brilliance who all seemed to gaze skyward.
Solar events made the Nürnberg news, and it took little time for such happenings to be contemplated and deciphered by wisemen and the clergy. It was also a domino effect, for through the preoccupation with astronomy, many discoveries took place in mathematics and the sciences. Not only was the city producing great minds, it was creating scientific tools of immense beauty.
Johannes Müller, or Regiomontanus, matriculated in Vienna in 1450 as Johannes Molitoris de Kunigsperg, the most important astronomer of the 15th century. Born to a mill keeper in a small Frankonian town, he was sent to Leipzig to study at age twelve. In 1436, he attended the Universities of Leipzig and then Vienna, where he studied with the celebrated astronomer George of Peurbach (1423-61) who was also a Master at Vienna, and they two made observations together, for example, they observed the planet Mars being two degrees off the place assigned to it and a lunar eclipse over an hour late on the Tables.
When the Greek scholar Cardinal Bessarion of Trebizond arrived in Vienna as papal legate to the emperor, a whole world opened up to the men. Having changed to the Latin Rite, Bessarion mastered the Latin language like his own, and began translating Ptolemy directly from the Greek. Peurbach was also engaged in composing an epitome on Ptolemy’s “Almagest.” Neither of them was able to accomplish his task alone. They agreed that Peurbach should accompany Bessarion to Italy, together with Müller, but when Peurbach died in 1461 Müller promised to complete his work “Epitome,” the abridgement of Ptolemy’s Syntaxis. This work, later used by Copernicus, Galileo and others, was finished by 1463 and printed as the “Epitome of the Almagest” in 1496.
After Peurbach’s death, Regiomontanus (Müller) went to Rome and searched libraries for Greek manuscripts on mathematical and astronomical subjects in his travels around Italy, becoming fluent in Greek. What manuscripts he could not acquire, he copied using a New Testament he’d written in Greek as his guide. He finally could understood the whole of Ptolemy, and was able to complete the “Epitome” of Peurbach by adding seven books to the six already written by his master.
He continued his observations in Vienna and refuted the quadrature of the circle given by Cuse and computed a calendar with the places of sun and moon, the eclipses and the dates of Easter for the next thirty years. He spent four more years in Rome and then apparently spent the next three years in Hungary under King Matthias Corvinus as custodian of the library abundant with treasures from Constantinople and Athens. The ensuing Bohemian wars of the king, however, led Müller to look for a quiet place where he could carry out his work, and he decided upon Nürnberg, then the center of industry, intellect and commerce in southern Germany. In 1471, he wrote in a letter to a friend on 4 July 1471: “Quite recently I have made observations in the city of Nürnberg... for I have chosen it as my permanent home not only on account of the availability of instruments, particularly the astronomical instruments on which the entire science is based, but also on account of the great ease of all sorts of communication with learned men living everywhere, since this place is regarded as the center of Europe because of the journeys of merchants. “
In the fall of 1471, he was welcomed to the city and furnished with an instrument shop, small observatory and a printing office. The great comet of 1472 was observed during January and February in such a way that its orbit could be calculated. He wrote details of his instruments in Scipta and these, including dials, quadrants, safea, astrolabes, armillary astrolabe, torquetum and the parallactic ruler. His observations of this comet, using his Jacob’s staff, were accurate enough to allow it to be identified with Halley’s comet 210 years later.
Müller’s ideas of the motion of the Moon led him to make the important observation that the method of lunar distances could be used to determine longitude at sea. It was many years, however, before a degree of accuracy necessary for the method was developed. He described how the moon’s position can be used to determine longitude in the Ephemerides, for the years 1474-1506, with the positions of the sun, moon, planets and the eclipses from 1475 to 1500 published on his printing press. This guided Columbus to America and enabled him to predict the lunar eclipse of February 29, 1504. Amerigo Vespucci also used Müller’s Ephemerides to measure longitudes in the New World.
His patron and co-worker Bernhard Walther’s print shop, with the improved methods and types designed by Müller, published several texts, including the first edition of the Disputationes contra Cremonensia (c. 1475) and an astronomical poem of Manilius (1472-73). Purbach’s Theoricae novae planetarum, which is the third and last work in the book being described, was also printed. In this work Purbach gave a rather detailed account of the theory of the planets, and pointed out “the discrepancy between the views of Aristotle and those of Ptolemy.”
The second and third parts of this book were first printed at Nürnberg by Müller and the printer Erhard Ratdolt, a master at printing scientific works. Most importantly, Müller’s own “Calendarium Novum” was printed. He became the first publisher of this type of scientific literature which included ancient, medieval and modern works. Müller’s scientific activity in Nürnberg ended when Sixtus IV called him to Rome to settle the reforming of the calendar. Müller was reportedly created Bishop of Ratisbon, although he never occupied the episcopal chair. In Rome, towards the end of 1475, Müller died at age forty.
The cause of his death was possibly a pestilence in Rome caused by the Tiber overflowing its banks. Many of his manuscripts and works were lost, in particular everything on the reform of the calendar. Some works were published posthumously, including the five books on triangles and the quadrature of the circle. Müller made important contributions to both trigonometry and astronomy.
One of the old books which he found while he was in Venice was an incomplete copy of Diophantus’s Arithmetica. He wrote to the mathematician Giovanni Bianchini in 1464 offering a Greek translation of the text if he could find a complete copy. Nobody ever did, but while Müller never did translate Diophantus’s Arithmetica, and never found a complete version, this important discovery by Müller marks the beginning of the Arithmetica becoming known in Europe.
In the Epitome, Müller, seeing the need for a systematic account of trigonometry to support astronomy, later wrote such a treatise and his book De triangulis omnimodis (1464) is a systematic account of methods for solving triangles. When he was in Hungary, he computed two tables of sines. The first computed in 1467 was Tables of directions which was based on sexagesimal numbers, while in the following year in Buda he computed tables of sines to a decimal base.
One famous pupil of Regiomontanus was said to be Nürnberger Martin Behaim, who is believed to have studied mathematics with him. Behaim, born around 1459, was the son of a wealthy merchant and he took up the trade himself, travelling through much of Western Europe in search of textiles. He traveled to Lisbon, Portugal sometime in his twenties and was welcomed by Portuguese King John II. It is said that Behaim met Christopher Columbus here. Behaim’s extensive knowledge impressed the King of Portugal, and his mathematical and navigational skills earned him an appointment to the King’s council of mathematicians around 1483.
Among Behaim’s accomplishments were complex innovations and improvements to navigational instruments such as conjoining the cross-staff apparatus which determined ship altitude to the sun declension tables of Regiomontanus. He was knighted in the Portuguese Order of Christ by King John II in 1484 and in 1485, he accompanied the cosmographer Diego Cam on a southbound expedition to explore the West Coast of Africa. On the return voyage from Africa in 1486, the expedition stopped in the Azores and Behaim stayed there for several years and married the daughter of the governor.
Here, he established a Flemish colony before returning to Nürnberg in 1490, when the city commissioned him to create the Terrestrial Globe, the first known such globe to be made since those of the ancient Greeks, for today’s price of 75 dollars. Artists who worked to his specifications and it took him a year to complete it. It was extensively decorated and contains 48 banners, 15 coats of arms, zodiac symbols, miniature drawings of saints, kings, ships, animals, fish and even a mermaid and a merman. His Globe was dubbed the Erdapfel (earth apple) by the Nürnberg townsfolk. His work done, he then resumed his travels and returned to Portugal shorty after. He spent his later years as an emisary to Belgium and the Netherlands, a position which necessitated traveling back and forth from Portugal, and on one of these occasions, he was captured by the English and taken to England, where he escaped and returned to Portugal. There he remained until his death in 1507. The globe survives today, and is considered to be the oldest such artifact of its kind.
In 1688, he had to close it for a time when French invasion threatened. When it reopened at the end of the century, this was the only large observatory in Germany. The artistic work of Eimmart was closely connected to the sky charts and maps, as well as his globes. Observatory, above
His daughter, Maria, also developed a keen interest in astronomy as a child. She was taught mathematics, Latin, French and mathematics as well as etching and drawing by her father. She became an important aide to her father in the observatory. After the death of her father, the observatory was purchased by the city, and they hired Johann Heinrich Mueller (1671-1731) as the new director. Marie married him, but she died in childbirth one year later. Maria Clara Eimmart was a capable astronomical observer, and between 1693 and 1698, she sketched about 250 scenes of the moon. On May 12, 1706, she could observe the total solar eclipse from the observatory. Some of her astronomical paintings and 57 thick volumes of her father’s work sadly ended up in Russia, although some of her drawings are in the possession of the observatory in Bologna, Italy.
A crater on the moon was named after Eimmart by Johann Hieronymus Schroeter (1745-1816) around 1800. The significance of Eimmart observatory, all but destroyed by Allied bombing, lies in that it was the first public observatory in Nürnberg and hosted special celestial events for the population and created great enthusiasm in astronomy. Some of its assistants contributed vastly to astronomy and geography.
Mechanical clocks and watches were wildly popular in Baroque Germany, but ornamental sundials in fancy gardens were enjoyed, too, and the more complicated the better. Highly mathematical sundials were designed in geometric shapes and plastered on everything from beer mugs to bird baths and even put on gravestones. Nurnberg was a leader in the craze of the intricate Baroque garden with their sundials, and some actually survive today.
All during the Renaissance and Baroque periods until 1786, Nurnberg was the creative design and building center of sundials. Seventy three public sundials existed in the city. The keen interest in the solar system did not abate for a long time. Georg Friedrich Kordenbusch (1731-1802) was educated as a medical doctor but became teacher of mathematics and physics. He attempted in vain to revitalize the Nürnberg Observatory, which had been torn down in 1751. In the early 1770s, he became famous for issuing the second edition of Johann Leonhard Rost’s Astronomisches Handbuch, the first compendium of astronomy written in German. He also edited and translated some French works (star maps, a description of globes, and an elementary book on cosmography). In 1790, Kordenbusch was raised to the nobility. From the Toplerhaus in Nürnberg the physician Kordenbusch first observed the planets with a Gregorian reflector.
In 1796, the city of Nurnberg was occupied by the French army, and although this occupation lasted only 14 days, they took 18 prominent citizens as hostages for ransom, Kordenbusch being among them. They were taken near the Belgian border and it was not until the end of July 1797, he was able to return to Nurnberg. Alas, in 1945 the Toplerhaus, along with the rest of ancient and venerable Nürnberg was completely destroyed by an Allied air raid. It is ironic that its destruction would come from the skies.