Category Archives: Renaissance Science

Der Erdapfel

Erdapfel is the word for potato in my local Franconia dialect, in fact in most of Southern Germany and Austria. In High Germany a potato is ein Kartoffel. Don’t worry this is not a post about root vegetables or variations in German regional dialects. Der Erdapfel is also the name given to the so-called Behaim Globe, the oldest known surviving terrestrial globe, Nürnberg’s most famous historical artefact. The name, which literally translates as Earth Apple, is thought to be derived from the medieval term Reichsapfel (Empire Apple), which was the name of the Globus Cruciger, or orb, as in orb and sceptre, the symbols of power of the Holy Roman Emperor; the orb symbolising the earth. The Behaim globe, which was conceived but not constructed by Martin Behaim, is together with Behaim, the subject of many historical myths.


Martin Behaim was born in Nürnberg in 1459 and lived with his parent on the market place next door to the businessman Bernhard Walther (1430–1504) who was the partner to Regiomontanus in his printing and astronomical activities during the last five years of his life living in Nürnberg. Martin’s father was one of the rich traders, who dominated Nürnberg culture. In 1576 he was sent away to Flanders to apprentice as a cloth trader. In 1484 he journeyed to Portugal, which is where to mythological part of his life begins. According to the traditional version of his life story he took part in two sea voyages down the west coast of Africa with Diogo Cão. He was knighted by the Portuguese king and appointed to the Portuguese Board of Navigation. All of this took place because he was supposedly a student of Regiomontanus, whose ephemerides, the first ever printed ones and highly accurate, were well known and respected on the Iberian Peninsula. All of this information comes from Behaim himself and some of it can be read in the texts on the Behaim Globe.


Artist's impression of Martin Behaim with his globe. Artist unknown

Artist’s impression of Martin Behaim with his globe. Artist unknown

Between 1490 and 1493 Behaim returned to Nürnberg to sort out his mother’s testament and it was during this period that he persuaded to city council to commission him to produce a globe and a large-scale wall map of the world. It is not certain if the wall map was ever produced and if it was it has not survived but the globe certainly was and it is now, as already said, the oldest known surviving terrestrial globe. It is not however, as is often falsely claimed the oldest or first terrestrial globe. The earliest recorded terrestrial globe was constructed by Crates of Mallus in the second century BCE. Also Ptolemaeus in his Geographia, in his discussion of different methods of cartographical projection, acknowledges that a globe in the only way to accurately represent to earth. The Behaim Globe is not even the earliest European medieval globe as the Pope in known to have commissioned earlier terrestrial globes, which have not survived. Given their method of construction and the materials out of which they are made the survival rate of globes is relatively low.

The globe remained the property of the city council of Nürnberg until the middle of the sixteenth century when it was returned to the Behaim family who basically threw it into the corner of an attic and forgot about it. In the nineteenth century it was rediscovered and studied by various historians of cartography and a copy was made for a museum in Paris. Unfortunately it was also ‘restored’ several times through processes that did far more damage than good. In the early twentieth century it was lent to the Germanische Nationalmuseum in Nürnberg. In the 1930s the Behaim family considered selling the globe, most probably in America, and to prevent this Adolf Hitler bought the globe with his own private money and presented it to the German nations. It still resides in the Germanische Nationalmuseum.

I said that the globe is veiled in myths and we will start to sort them out. Firstly Behaim only conceived the globe he didn’t construct it as many people believe. The globe was made by pasting strips of linen onto a fired clay ball. The ball produced by Hans Glockengiesser (a family name that translates as bell founder) and the globe constructed by Ruprecht Kolberger. After the paste had set the globe was cut free from the clay form by a single cut around its equator and the two halves we then pasted together on a wooded frame. The actually map was painted onto the linen ball by the painter and woodblock cutter Georg Glockendon and the lettering was carried out by Petrus Gegenhart. Behaim only seems to have directed and coordinated these activities.


Another popular myth is that because of Behaim’s activities in Portugal the cartography of the globe is cutting edge up to the minute modern; nothing could be further from the truth. The basis of the cartography is Ptolemaeus with obvious additions from other ancient Greek sources as well as The Travels of Sir John Mandeville and The Travels of Marco Polo. Much of the cartographical work is inaccurate even by the standards of the time, including surprisingly the west coast of Africa that Behaim supposedly had explored himself, which brings us to Behaim’s personal claims.


His claim to have sailed with Diogo Cão is almost certainly a lie. At the time of Cão’s first voyage along the African coast Behaim is known to have been in Antwerp. On his second voyage Cão erected pillars at all of his landing places naming all of the important members of the crew, who were on the voyage, Martin Behaim is not amongst them. They is no confirmatory evidence that Behaim was actually a member of Portuguese Board of Navigation and if he was his membership almost certainly owed nothing to Regiomontanus, as there is absolutely no evidence that he ever studied under him. The historian of navigation, David Waters, suggests that if Behaim was actually a member of this august body then it was because the Portuguese hoped to persuade the rich Nürnberger traders to invest money in their expeditionary endeavours, Behaim thus functioning as a sort of informal ambassador for the Republic of Nürnberg.

The picture that emerges is that Martin Behaim was con artist probably deceiving both the Portuguese court and the Nürnberg city council. The Behaim Globe is an interesting artefact but its historical or scientific significance is minimal. If you are in Nürnberg, I can recommend going to the Germanische Nationalmuseum to see it but when you are there also take a look at the Schöner 1520 terrestrial manuscript globe in the neighbouring room. It’s cartographically much more interesting and Schöner, as opposed to Behaim, plays a very important role in the history of globe making.


Johannes Söner's 1520 terrestrial Globe. Germanische Nationalmuseum

Johannes Söner’s 1520 terrestrial Globe.
Germanische Nationalmuseum




Filed under History of Cartography, History of science, Myths of Science, Renaissance Science, Uncategorized

Made in Nürnberg

In the period from roughly 1550 and 1650 Nürnberg was the leading centre in Europe, and thus probably the world, for the manufacture of scientific instruments. It is historically interesting to look at how this town in the middle of Europe came to acquire this status and also to take a brief look at some of the more famous of the Nürnberger instrument makers from this ‘golden’ period.

Like many European towns and cities, Nürnberg, as an entity, began to emerge at the beginning of the High Middle Ages, probably around the year 1000 CE. Like many such settlements it was initially not much more than a fortified hill top at a crossroads. The first record of the name is 1050 CE as nuorenberc, which later evolved into Nuremberg, the name by which it is still known in English. This name is the subject of a rare German bad pun; the Germans don’t really go in for puns. According to folk etymology the name was originally ‘Nur einem Berg’, which translates as ‘just a hill’. The geographical position of Nürnberg played an important role in its development. If you take an outline map of Europe and draw a straight line from Kiel, in Northern Germany, to Northern Italy and a second one from Paris to Prague, the point where they cross is Nürnberg. This led to Nürnberg becoming a major European trading hub in the medieval period; importing wares from the Northern Italian trading cities and then distributing them throughout Europe.

Germany didn’t exist as a country in the Middle Ages but was a loose conglomerate of large and small states interconnected through a network of feudal obligations and vaguely held together in the so-called Holy Roman Empire, which as somebody once quipped was neither holy nor Roman nor an empire. Within this patchwork of large and small Germanic states Nürnberg was one of the so-called Free Imperial Cities, small independent city-states, which only owed feudal allegiance to the Holy Roman Emperor. From 1105 CE Nürnberg was ruled by a hereditary Burggraf, a title that translates as Lord of the castle. From 1192 till 1427 the Burggrafen of Nürnberg came from the Hohenzollern family, who would go on to play a significant role in German history. In 1427 the rich traders of Nürnberg, of whom more shortly, bought the Burggraf rights from the Hohenzollern and from then on until 1806, when Nürnberg became part of Bavaria, the city was ruled by the town council. Although dominated by the rich trader families the town council was surprisingly democratic with three groups of councillors being appointed/elected from the three tiers of citizenry at regular intervals. During the Renaissance Nürnberg, like one of its major trading partners Venice, called itself a republic.

The Holy Roman Emperor granted the city of Nürnberg special tax privileges, which combined with its favourable geographical position and the large Europe wide demand for the spices that came into Europe through the Northern Italian trading cities meant that the Nürnberg traders became very, very wealthy. This led to them looking for new opportunities to invest their surplus profits. The High Middle Ages saw a steeply rising demand for metals (gold, silver, copper, lead, iron) and with it an expansion of the metal ore mining industry. The major ore deposits, and thus the mines, were situated in the eastern part of Middle Europe, Eastern Germany, Hungary, Rumania, Austria etc. Realising that it was an expanding business with a future the Nürnberg traders began investing in the metal ore mines and soon controlled a large part of this industry. At first content just to sell the ore they soon realised that they could make more profit if they smelted the ore themselves and so built their own smelters and began selling refined metal. It did not take long before the artisans of Nürnberg began to work the metal themselves producing finished metal objects for sale. By the fifteenth century Nürnberg had become one of the major metal working centres of Europe producing quite literally everything that could be made from metal from pins and needles to suits of armour. A sign of this development is that the first mechanical wire drawing machine was developed in Nürnberg. The Nürnberg guilds were incredibly well organised with single families responsible for the production of one object or group of objects. When Karl V (Holly Roman Emperor 1519–1556) ordered 5000 suits of armour from Nürnberg, one group of families was responsible for the leg plates, another for the breast plates and so on. Highly organised piecework.

Nürnberg as depicted in the Nuremberg Chronicles 1493

Nürnberg as depicted in the Nuremberg Chronicles 1493

Of course many scientific instruments are made of metal, mostly brass, and so Nürnberg in its all inclusiveness became a major centre for the manufacture of all types of scientific instruments. In fact it became the leading European centre for this work and thus, most probably, the leading world centre in the fifteenth and sixteenth centuries. We have two important historical attestations of Nürnberg’s supremacy in this area. The philosopher Nicholas of Cusa (Cusanus) (1401–1464) was very interested in astronomy and he purchased a celestial globe and other astronomical instruments from Nürnberg and this can still be viewed in the Cusanus Museum in his birthplace Kues. In 1470 when Johannes Regiomontanus set out to reform and modernise astronomy he moved from Budapest to Nürnberg because, as he tells us in a letter, Nürnberg had a good communications network through which he could communicate with other astronomers and because the best astronomical instruments were manufactured in Nürnberg. The communications network was an essential element of any Renaissance trading city and Nürnberg’s was second only to that of Venice.

By 1500 Nürnberg was the second biggest German city with a population of around 40 000, half of which lived inside the city walls and the other half in the surrounding villages, which belonged to the city. It was one of the richest cities in the whole of Europe and enjoyed a high level of culture, investing both in representative architecture and the arts, with many of the leading German Renaissance artists fulfilling commissions for the rich Nürnberg traders, known locally as the Patrizier; most famously Albrecht Dürer. Interesting in our context, Dürer’s maths book contained the first printed instructions in German of how to design and construct sundials. The first half of the sixteenth century was the golden age of scientific instrument production in Nürnberg with many of the leading instrument makers selling their wares throughout Europe, where they can still be found in museums in many different countries. In what follows I shall give brief sketches of a couple of the more well known of these craftsmen.

Nürnberg was famous for it’s portable sundials with family dynasties producing high quality products over three, four or even five generations. At the beginning of the sixteenth century the most significant sundial maker was Erhard Etzlaub (ca. 1460–1532) who like many other Nürnberger instrument makers was as much as a scholar as an artisan. As a cartographer he produced the first map of the Nürnberg region. He followed this with the so-called Rome pilgrimage map displaying the routes to Rome for the Holy Year of 1500, which famously Copernicus also attended. This map plays an important role in the history of modern cartography because it’s the first map with a scale, enabling the pilgrim to plan his daily journeys.

Etzlaub's Rome Pilgrim Map Source: Wikimedia Commons

Etzlaub’s Rome Pilgrim Map
Source: Wikimedia Commons

Etzlaub also constructed a map on the cover of one of his compasses in 1511 that is drawn in a projection that comes close to the Mercator projection. Etzlaub was a member of the so-called Pirckheimer Circle. A group of like minded proponents of the mathematical sciences centred around Willbald Pirckheimer, soldier, politician humanist scholar and translator from Greek into Latin of Ptolemaeus’ Geographia; a translation that became a standard work.

Willibald Pirckheimer, porträtiert von Albrecht Dürer (1503) Source: Wikimedia Commons

Willibald Pirckheimer, porträtiert von Albrecht Dürer (1503)
Source: Wikimedia Commons

This group of mathematical scholars demonstrated their interest in the mathematical sciences and in the construction of complex instruments in the highly complex sundial that they painted on the side of the Lorenzkirche in 1502, which also displays the time according to the Great Nürnberger Clock:

Lorenzkirche Sundial Source: Astronomie in Nürnberg

Lorenzkirche Sundial
Source: Astronomie in Nürnberg

And the clock on the Frauenkirche constructed in 1506:

Frauenkirche Clock

Frauenkirche Clock

The gold and blue ball above the clock dial displays the phases of the moon and is still accurate today.

Another member of the Pirckheimer Circle was Johannes Schöner(1477–1547), addressee of Rheticus’ Naratio Prima, the first published account of Copernicus’ heliocentrism.

Johannes Schöner Source: Wikimedia Commons

Johannes Schöner
Source: Wikimedia Commons

Schöner was the first producer of serial production printed globes both terrestrial and celestial. He also wrote, printed and published pamphlets on the design and manufacture of various scientific instruments. Schöner was Europe’s leading globe maker whose globes set standards for globe making, which influenced the manufacture of globes down to the nineteenth century.

Schöner Celestial Globe 1535 Source: Science Museum London

Schöner Celestial Globe 1535
Source: Science Museum London

Also a member of the Pirckheimer Circle and a close friend of Schöner’s was Georg Hartman (1489–1564).

Georg Hartmann Source: Astronomie in Nürnberg

Georg Hartmann
Source: Astronomie in Nürnberg

Hartmann like Schöner was a globe maker although none of his globes have survived. He was also one of the leading sundial makers of his generation and his complex and beautiful dials can still be found in many museums.

Hartmann Bowl Sundial Source: Wikimedia Commons

Hartmann Bowl Sundial
Source: Wikimedia Commons

In the early sixteenth century Nürnberg was the main European centre for the production of astrolabes and here Hartmann played a leading role. As far as can be ascertained Hartmann was the first person to produce astrolabes in series.

Hartmann Astrolabe Yale Source: Wikimedia Commons

Hartmann Astrolabe Yale
Source: Wikimedia Commons

Previously all astrolabes were produced as single pieces, Hartmann, however, produced series of identical astrolabes, probably employing other craftsmen to produce the individual parts according to a pre-described plan and them assembling them in his workshop. As a young man Hartmann had spent several years living in Italy where he was friends with Copernicus’ brother Andreas. As a scholar Hartmann was the first to investigate magnetic inclination or dip. However his studies were never published and so the credit for this discovery went to the English mariner Robert Norman.

Handmade metal instruments were, of course, very expensive and could in reality only be purchased by the wealthy, who often bought them as ornaments of status symbols rather than to be used. To make scientific instruments available to those with less money both Schöner and Hartmann produced paper instruments. These consisted of the scales and tables, normally found engraved on the metal instruments, printed accurately on paper, which the user could then paste onto a wooden background and so construct a cheap but functioning instrument.

Paper and Wood Astrolabe Hartmann Source: MHS Oxford

Paper and Wood Astrolabe Hartmann
Source: MHS Oxford

A later instrument maker was Christian Heiden (1526–1576) who like Schöner was professor for mathematics on the Egidiengymnasium in Nürnberg, Germany’s first gymnasium (similar to a grammar school). He made a wide range of instruments but was especially well known for his elaborate and elegant sundials, as much works of art as scientific instruments these were much prized amongst the rich and powerful and could be found on many a German court.

Column Sundial by Christian Heyden Source: Museumslandschaft Hessen-Kassel

Column Sundial by Christian Heyden
Source: Museumslandschaft Hessen-Kassel

This is of course only a very, very small sample of the Nürnberger instrument makers, the history pages of the Astronomie in Nürnberg website, created and maintained by Dr Hans Gaab, lists 44 globe makers, 38 astronomical instrument makers and more than 100 sundial makers between the fifteenth and nineteenth centuries; with the greatest concentration in the sixteenth century. Nürnberg was known throughout Europe for the quality and the accuracy of its scientific instruments and examples of the Nürnberger handwork can be found in museums in many countries, even outside of Europe.


Filed under History of Astronomy, History of science, History of Technology, Renaissance Science

Abraham Ortelius and the 16th century information age.

The sixteenth century saw the evolution of modern cartography emerge out of a renaissance in Ptolemaic cartography. In the second half of the century the Netherlands played a leading role in this process. I have already blogged twice about Gerard Mercator the man most closely associated with the modern cartography, here and here, and also about his teacher Gemma Frisius, so today I want to turn my attention to Mercator’s friend and rival Abraham Ortelius.


Abraham Ortelius by Peter Paul Rubens Source: Wikimedia Commons

Abraham Ortelius by Peter Paul Rubens
Source: Wikimedia Commons

He was born Abraham Ortel (as we most Renaissance scholars there are numerous variant spellings of the family name) in Antwerp on 14 April 1527, to where his grandfather William had moved the family from Augsburg in Southern Germany in 1460, supposedly because of religious persecution. The son of a merchant who died whilst he was still young, in about 1535. Ortelius studied mathematics, Latin and Greek as a youth and apprenticed as an engraver of maps and entered the Antwerp guild of map illuminators in 1547. He set a shop trading in books, prints and maps with his sister and became an engraver for the highly influential Plantin publishing house. Through his various activities as a trader Ortelius came to travel extensively throughout Europe, visiting all the regions of Germany, Italy, France, England and Ireland.

He met and became friends with Gerard Mercator at the Frankfurt book Fair in 1554. In 1559-1560 he accompanied Mercator on his cartographical expedition through Trier, Lorraine and Poitiers. It was during this trip that Mercator is supposed to have persuaded his friend to not just engrave and colour other people’s maps but to become a cartographer in his own right.

Following the example of his mentor, Ortelius started out producing single maps sold as prints. His first effort was an eight-sheet world map produced in 1564. This was followed by a two-sheet map of Egypt (1565), a single-sheet map of the Holy Land in 1566, a two-sheet map of Asia (1567) and a six-sheet map of Spain (1570). Ortelius’ entry into the map business was a success. Gemma Frisius, Mercator and Ortelius were all cartographers and businessmen. However, whereas it is safe to say that Gemma Frisius and Mercator were cartographers first and businessmen second in the case of Ortelius it was the other way round; he was very much a businessman first and a cartographer second.


Ortelius' World Map 1564 Source: Wikimedia Commons

Ortelius’ World Map 1564
Source: Wikimedia Commons

Given the massive increase in international trade and the travel involved in it, there was a strong increase in the demand for good maps. To save themselves the trouble of carrying around large bundles of loose maps various people had started collecting together maps from various sources and binding them together in a book. However, the maps in such collections were of different styles, varying qualities and highly varying usefulness. Ortelius and his business partners came up with the idea of printing and publishing a comprehensive collection of maps of uniform size all in the same style and containing the most up to date geographical data available. Published by Ortelius and printed by Egidius Coppens van Diest the first edition of Ortelius’ Theatrum orbis terrum (the first modern atlas!?) containing fifty-three maps appeared in 1570.


Theatrum Orbis Terrarum Title Page Source: Wikimedia Commons

Theatrum Orbis Terrarum Title Page
Source: Wikimedia Commons

Ortelius didn’t produced the maps from scratch himself but relied on the maps of other cartographers, modifying and improving them as he reproduced them in his uniform style oft incorporating elements of several maps into his finished product. This method of working was not new but had been employed by the leading cartographers throughout the sixteenth century, where Ortelius differed was in that he included a Catlogus cartographorum, a list of eighty-seven cartographers whose work he had used to compose his Theatrum. The Theatrum was a major success going through forty editions between 1570 and 1624. As well as numerous Latin editions there were also several editions each in German, French, Italian, Spanish and English. The Theatrum was very definitely a sixteenth-century bestseller.


Map of the Persian Empire from the Theatrum Orbis Terrarum Source: Wikimedia Commons

Map of the Persian Empire from the Theatrum Orbis Terrarum
Source: Wikimedia Commons

One of the most important features of the Theatrum was its evolution. Each new edition would be modified and updated with as much new information as Ortelius could obtain.

Starting with 53 maps in 1570, it grew to 70 maps in 1573, 93 maps in 1579, 122 maps in 1584 and in the final edition prepared by Ortelius and published in 1590, one year after his death, 134 maps. Plantin had been involved in marketing and selling the Theatrum from the very beginning and took over printing it in 1579 uptil his own death in 1589.

Of interest is a pocket sized version, or epitome, of the Theatrum that was published by Philips Galle and printed by Plantin beginning in 1577. Like the original this too went through many editions in several different languages, the first edition having been in Dutch.

The evolution of the Theatrum between its birth in 1570 and Ortelius’ death in 1589 is a wonderful example of the so-called Republic of Letters in operation in the Early Modern Period. Ortelius had connections all over Europe and even further afield amongst the scholars of his day. Through correspondence they supplied him with the information he needed to update and modernise his maps. Also supplying the geographical and historical information with which he annotated later editions of his magnum opus. This information network worked in both directions with Ortelius passing on information he had received from one member of the network to others he thought might be interested. This correspondence did not only deal in matters geographical and cartographical but also included much information from all the various branches of natural history. An impression of Ortelius’ correspondence network can be gained from his Album Amicorum (friendship book), which he maintained from 1574 to 1596. It has 130 entries that read like a who’s who of the European intellectual elite of the period.


Maris Pacifici, 1589, the first dedicated map of the Pacific to be printed Source: Wikimedia Commons

Maris Pacifici, 1589, the first dedicated map of the Pacific to be printed
Source: Wikimedia Commons

Ortelius’ second major geographical work was his Synonymia Geographica sive Popularum, Regionum, Insularum, Urbium… Appelationes et Nomina, originally an appendix in the Theatrum but then published in expanded form as a separate volume beginning in 1578. This is a list of classical place names identifying their modern locations based on Ortelius’ own historical research, an important research tool for anybody studying classical works.

Another minor claim to fame possessed by Ortelius is that he appears to be the first person to have suggested a theory of continental drift based on his recognition that the continents surrounding the Atlantic basin seemed to fit together. He suggested that the Americas had been torn away from Europe and Africa by earthquakes and floods. His theory fell on deaf ears in his own times.

We still have one rather important linguistic question to clear up. If the ‘first modern atlas’, was entitled the Theatrum orbis terrum by Ortelius, its creator, then why do we call a collection of maps an atlas?

Almost at the same time as Ortelius, his friend Mercator embarked on a very similar project if his motivation was somewhat different. I have blogged about Mercator’s map collection, which he called an atlas already here so I won’t repeat the story now. Mercator’s book only appeared in full, bearing for the first time the title Atlas, posthumously in 1595, twenty-five years after the first appearance of the Theatrum. Although Mercator’s work was without doubt superior to Ortelius’, the later was already a well-established best seller and the larger more complex work of Mercator failed to seriously challenge the market leader. Had the situation remained as it was, we would probably still refer to a bound collection of maps as a theatre. In case you are wondering Ortelius’ original title translates as something like view of the earthly globe. However at the end of the 1590s things changed. Ortelius died and although his Theatrum continued to appear until 1624 nobody took the trouble to update it. On the other hand Mercator’s son died in 1599 and Jodocus Hondius a cartographical publisher and globe maker from Amsterdam bought up the rights to Mercator’s Atlas. Hondius did update and modify Mercator’s work and so took over dominance in the market. In 1624 Hondius’ biggest rival Willem Janszoon Blaeu bought the rights to Ortelius’ Theatrum incorporating it into his own map book that he titled an atlas in imitation of Hondius. And so it is that we now call a bound collection of maps an atlas and not a theatre.









Filed under History of Cartography, Renaissance Science

A Swiss Clockmaker

We all have clichéd images in our heads when we hear the names of countries other than our own. For many people the name Switzerland evokes a muddled collection of snow-covered mountains, delicious superior chocolates and high precision clocks and watches. Jost Bürgi who was born in the small town of Lichtensteig, in the  Toggenburg region of the canton of St. Gallen on 28 February 1552 fills this cliché as the most expert clockmaker in the sixteenth century. However Bürgi was much more that just a Swiss clockmaker, he was also an instrument maker, an astronomer, a mathematician and in his private life a successful property owner and private banker, the last of course serving yet another Swiss cliché.

As we all too many figures, who made significant contributions to science and technology in the Renaissance we know next to nothing about Bürgi’s origins or background. There is no known registration of his birth or his baptism; his date of birth is known from the engraving shown below from 1592, in which the portrait was added in 1619 but which was first published in 1648. That the included date is his birthday was confirmed by Bürgi’s brother in law.


His father was probably the locksmith Lienz Bürgi but that is not known for certain. About his education or lack of it nothing is known at all and just as little is known about where he learnt his trade as clockmaker. Various speculations have been made by historians over the years but they remain just speculations. The earliest documentary proof that we have of Bürgi’s existence is his employment contract when he entered the service of the Landgrave Wilhelm IV of Hessen-Kassel as court clockmaker, already twenty-seven years old, on 25 July 1579. Wilhelm was unique amongst the German rulers of the Renaissance in that he was not only a fan or supporter of astronomy but was himself an active practicing astronomer. In his castle in Kassel he constructed, what is recognised as, the first observatory in Early Modern Europe.

Wilhelm IV. von Hessen-Kassel Source: Wikimedia Commons

Wilhelm IV. von Hessen-Kassel
Source: Wikimedia Commons

He also played a major role in persuading the Danish King Frederick II, a cousin, to supply Tycho Brahe with the necessary land and money to establish an observatory in Denmark. In the 1560s Wilhelm was supported in his astronomical activities by Andreas Schöner, the son of the famous Nürnberger cartographer, globe and instrument maker, astronomer, astrologer and mathematician Johannes Schöner. He also commissioned the clockmaker Eberhard Baldewein (1525-1593) to construct two planet clocks and a mechanical globe.


Eberhart Baldewein Planet clock 1661 Source: Wikimedia Commons

Eberhart Baldewein Planet clock 1661
Source: Wikimedia Commons

The planet clock shows the positions of the sun, moon and the planets, based on Peter Apian’s Astronomicom Caessareum, on its various dials.


Eberhard Baldewein Mechanical Celestial Globe circa 1573

Eberhard Baldewein Mechanical Celestial Globe circa 1573 The globe, finished by Heinrich Lennep in 1693, was used to record the position of the stars mapped by Wilhelm and his team in their observations.

These mechanical objects were serviced and maintained by Baldewein’s ex-apprentice, Hans Bucher, who had helped to build them and who had been employed by Wilhelm, for this purpose, since 1560. When Bucher died in 1578-1579 Bürgi was employed to replace him, charged with the maintenance of the existing objects on a fixed, but very generous salary, and commissioned to produce new mechanical instruments for which he would be paid extra. Over the next fifty years Bürgi produced many beautiful and highly efficient clocks and mechanical globes both for Wilhelm and for others.

Bürgi Quartz Clock 1622-27 Source: Swiss Physical Society

Bürgi Quartz Clock 1622-27
Source: Swiss Physical Society






Bürgi Mechanical Celestial Globe 1594 Source: Wikimedia Commons

Bürgi Mechanical Celestial Globe 1594
Source: Wikimedia Commons



Jost Bürgi and Antonius Eisenhoit: Armillary sphere with astronomical clock made 1585 in Kassel, now at Nordiska Museet in Stockholm. Source Wikimedia Commons

Jost Bürgi and Antonius Eisenhoit: Armillary sphere with astronomical clock made 1585 in Kassel, now at Nordiska Museet in Stockholm.
Source Wikimedia Commons

Bürgi was also a highly inventive clockmaker, who is credited with the invention of both the cross-beat escapement and the remontoire, two highly important improvements in clock mechanics. In the late sixteenth century the average clocks were accurate to about thirty minutes a day, Bürgi’s clock were said to be accurate to less than one minute a day. This amazing increase in accuracy allowed mechanical clocks to be used, for the first time ever, for timing astronomical observations. Bürgi also supplied clocks for this purpose for Tycho’s observatory on Hven. In 1592 Wilhelm presented his nephew Rudolph II, the German Emperor, with one of Bürgi’s mechanical globes and Bürgi was sent to Prague with the globe to demonstrate it to Rudolph. This was his first contact with what would later become his workplace. Whilst away from Kassel Bürgi’s employer, Wilhelm died. Before continuing the story we need to go back and look at some of Bürgi’s other activities.

As stated at the beginning Bürgi was not just a clockmaker. In 1584 Wilhelm appointed the Wittenberg University graduate Christoph Rothmann as court astronomer. From this point on the three, Wilhelm, Rothmann and Bürgi, were engaged in a major programme to map the heavens, similar to and just as accurate, as that of Tycho on Hven. The two observatories exchanged much information on instruments, observations and astronomical and cosmological theories. However all was not harmonious in this three-man team. Although Wilhelm treated Bürgi, whom he held in high regard, with great respect Rothmann, who appears to have been a bit of a snob, treated Bürgi with contempt because he was uneducated and couldn’t read or write Latin, that Bürgi was the better mathematician of the two might have been one reason for Rothmann’s attitude.

In the 1580s the itinerant mathematician and astronomer Paul Wittich came to Kassel from Hven and taught Bürgi prosthaphaeresis, a method using trigonometric formulas, of turning multiplication into addition, thus simplifying complex astronomical calculations. The method was first discovered by Johannes Werner in Nürnberg at the beginning of the sixteenth century but he never published it and so his discovery remained unknown. It is not known whether Wittich rediscovered the method or learnt of it from Werner’s manuscripts whilst visiting Nürnberg. The method was first published by Nicolaus Reimers Baer, who was then accused by Tycho of having plagiarised the method, Tycho claiming falsely that he had discovered it. In fact Tycho had also learnt it from Wittich. Bürgi had expanded and improved the method and when Baer also came to Kassel in 1588, Bürgi taught him the method and how to use it, in exchange for which Baer translated Copernicus’ De revolutionibus into German for Bürgi. This was the first such translation and a copy of Baer’s manuscript is still in existence in Graz. Whilst Baer was in Kassel Bürgi created a brass model of the Tychonic geocentric-heliocentric model of the cosmos, which Baer claimed to have discovered himself. When Tycho got wind of this he was apoplectic with rage.

In 1590 Rothmann disappeared off the face of the earth following a visit to Hven and for the last two years of Wilhelm’s life Bürgi took over as chief astronomical observer in Kassel, proving to be just as good in this work as in his clock making.

Following Wilhelm’s death his son Maurice who inherited the title renewed Bürgi’s contract with the court.


Kupferstich mit dem Porträt Moritz von Hessen-Kassel aus dem Werk Theatrum Europaeum von 1662 Source: Wikimedia Commons

Kupferstich mit dem Porträt Moritz von Hessen-Kassel aus dem Werk Theatrum Europaeum von 1662
Source: Wikimedia Commons

However Maurice did not share his father’s love of astronomy investing his spare time instead in the study of alchemy. Bürgi however continued to serve the court as clock and instrument maker. Over the next eight years Bürgi made several visits to the Emperor’s court in Prague and in 1604 Rudolph requested Maurice to allow him to retain Bürgi’s services on a permanent basis. Maurice acquiesced and Bürgi moved permanently to Prague although still remaining formally in service to Maurice in Kassel. Rudolph gave Bürgi a very generous contract paying him 60 gulden a month as well as full board and lodging. As in Kassel all clocks and globes were paid extra. To put that into perspective 60 gulden was a yearly wage for a young academic starting out on his career!

In Prague Bürgi worked closely with the Imperial Mathematicus, Johannes Kepler. Kepler, unlike Rothmann, respected Bürgi immensely and encouraged him to publish his mathematical works. Bürgi was the author of an original Cos, an algebra textbook, from which Kepler says he learnt much and which only saw the light of day through Kepler’s efforts. Kepler was also responsible for the publication of Bürgi’s logarithmic tables in 1620.


Bürgi's Logarithmic Tables Source: University of Graz

Bürgi’s Logarithmic Tables
Source: University of Graz

This is probably Bürgi’s greatest mathematical achievement and he is considered along side of John Napier as the inventor of logarithms. In many earlier historical works Bürgi is credited with having invented logarithms before Napier. Napier published his tables in 1614 six years before Bürgi and is known to have been working on them for twenty years, that is since 1594. Bürgi’s fan club claim that he had invented his logarithms in 1588 that is six years earlier than Napier. However modern experts on the history of logarithms think that references to 1588 are to Bürgi’s use of prosthaphaeresis and that he didn’t start work on his logarithms before 1604. However it is clear that the two men developed the concept independently of each other and both deserve the laurels for their invention. It should however be pointed out that the concept on which logarithms are based was known to Archimedes and had already been investigated by Michael Stifel earlier in the sixteenth century in a work that was probably known to Bürgi.

Through his work as clock maker Bürgi became a very wealthy man and invested his wealth with profit in property deals and as a private banker lending quite substantial sums to his customers. In 1631 Bürgi, now 80 years old, retired and returned ‘home’ to Kassel where he died in January of the following year shortly before his 81st birthday. His death was registered in the Church of St Martin’s on the 31 January 1632. Although now only known to historians of science and horology, in his own time Bürgi was a well-known and highly respected, astronomer, mathematician and clock maker who made significant and important contributions to all three disciplines.




Filed under History of Astronomy, History of Mathematics, History of science, Renaissance Science, Uncategorized

Do you believe in magic?

I’m in a bit of a quandary about this post for two different reasons. Firstly I didn’t really want to write yet another negative post at the moment and was considering various positive options when somebody drew my attention to the article that is going to be the subject of this one. However having once read through it I just couldn’t let it go. On the other hand having always been a powerful advocate of seriously investigating the so-called occult science activities of the scholars in the Early Modern period I find it slightly bizarre to now be giving the Hist-Sci Hulk treatment to an article that appears to do just that. The article in question is posted on the Vox website and is entitled, These 5 men were scientific geniuses. They also thought magic is real.

Before dealing with the ‘5 men’ there are a couple of general points of criticism that have to be levelled at this article. To begin with the whole thing is written in a supercilious tone of superiority. Despite the authors disclaimer, “We have the benefit of hindsight today, which gives us an unfair advantage over these geniuses” he creates the impression the whole time of ‘I’m just a simple Joe’ but I’m way more enlightened than these ‘geniuses’. Not a good way to approach any historical topic. The other major failure that weaves its way through the whole article is the equating of astrology, alchemy and magic, as one and the same thing. This is of course historically a serious mistake and disqualifies the entire article from the start. The grounds for justification, academic status and the levels of acceptance of the three disciplines differ from each other, as well as over time and place. Each one of them has to be dealt with separately within the given context and they cannot and should not be lumped together. This of course relates to the authors supercilious tone of superiority and is typical of the woolly thinking of all too many gnu atheists and adherents of scientism. Anything that doesn’t conform with their, often badly articulated, concept of science is dismissed as ‘magical thinking’ and as worthless. Let us now turn to the ‘5 men’.

First up we have Tuscany’s favourite son, Galileo Galilei who apparently believed “astrology changed everything”:

Today, Galileo (1564-1642) is held up as a paragon of rationality. He advocated heliocentrism — the idea that the sun, not the Earth, was at the center of the solar system — fought an anti-heliocentric church at great risk, and greatly advanced astronomy throughout Europe.

He also was something like a fortune teller.

Galileo didn’t just believe in astrology: he practiced it, conducted it for wealthy clients, and taught it to medical school students. If students at the University of Padua had taken MCATs, Galileo would have included a question about whether a Leo should date a Gemini.

Galileo wasn’t alone in keeping up on his signs. His contemporary, Johannes Kepler conducted his own astrological studies, though more reluctantly (he called people who believed in astrology “fatheads”).

Ignoring the opening paragraph and cutting to the chase a Renaissance astrologer, particularly an academic one, would object intensely to being referred to as ‘a fortune teller’. In the Renaissance astrology was generally accepted as a reputable academic disciple, a science i.e. a system of knowledge, whereas most other forms of divination i.e. fortune telling were frowned on as charlatanry. Here we have historical context, blithely ignored by our author, poking its nose in. Medical astrology, or iatro-mathematics, was a mainstream academic discipline taught at all Renaissance universities in the medical faculty, usually by the professor of mathematics. So if Galileo did indeed teach iatro-mathematics he would have been merely fulfilling the terms of his contract. I say if because it is to be assumed that Galileo did indeed teach such courses, however the proof that he did so doesn’t exists. The comment about ‘whether a Leo should date a Gemini’ is just plain stupid, as iatro-mathematics has nothing to do with judicial astrology, that is the everyday horoscope astrology, a completely different branch of the discipline.

Of course Galileo, who really did accept the truth of astrology, did practice judicial astrology famously casting and interpreting his own horoscope and those of his daughters. He also cast and interpreted the horoscopes not of ‘rich clients’ but wealthy patrons; there is a substantial difference. Rich clients would imply that Galileo’s services as an astrologer were for hire like any other street vendor, this was not the case. Rich patrons sought out Galileo’s company to share in his intellectual talents. Here his abilities to cast and interpret horoscopes became instruments of credit. Galileo entertained his patrons by supplying witty and stimulating after dinner discourses or debates or by providing the required horoscope. In exchange Galileo received favours from his patrons, a case of good wine, help with the cost of publishing his books or introductions to important and influential people such as the Pope.

On the good Johannes Kepler our author walks right into one of the most persistent myths of all in the history of science based on a classic case of quote mining, the claim that he was reluctant about astrology. Kepler was much more concerned about astrology, which he definitely believed in, than Galileo and wrote several books about it. However he totally rejected conventional horoscope astrology believing that the stars signs were artificial constructs with no significance whatsoever. He developed his own system based on planetary alignments, astrological aspects, and directio (directions, which I’m not going to explain!). Not unsurprisingly he didn’t find any takers for his reformed astrology. However his vitriolic diatribes against the conventional horoscope astrology and its practitioners, when quote mined, leads many people to the mistaken belief that he was in some way anti-astrology.

Our author next reveals, oh my god, that Newton was an alchemist. This is probably the most often ‘revealed secret’ about Grantham’s most famous son. This is titled “Isaac Newton thought alchemy was the future”, as we will see Newton was actually much more interested in alchemy’s past.

John Maynard Keynes called Isaac Newton (1642-1726) “the last of the magicians” with good reason. Newton spent half his life obsessed with alchemy, the transformative magic most frequently associated with turning different metals into gold. To make things even more complicated, in 1696, Newton became Warden of the Mint, and he became master of the Mint in 1700. The Royal Mint, of course, makes the coins for the entire United Kingdom. To be clear: an alchemist was the person in charge of making all the money.

Newton wasn’t the only respected mind who had visions of diving into gold coins. Robert Boyle is considered the father of chemistry, but he dabbled in alchemy as well. In fact, he was so committed to the alchemical cause that he fought to make alchemy legal, since Henry IV had banned it (because alchemy wasn’t good for the monetary supply). Needless to say, the repeal wasn’t necessary.

The philosopher’s stone Newton chased after wasn’t only able to “cure” metals that weren’t gold. It also had medical powers that fascinated Newton and his peers. Unfortunately, today you can only find the philosopher’s stone in the British subtitle of the first Harry Potter book.

Alchemy is not magic and any medieval or renaissance alchemist would have been deeply insulted if anybody had accused him of practicing magic. Alchemy as practiced by Newton or Boyle considered itself to be a well-founded knowledge system and it was this that attracted Newton. Newton certainly never had vision of diving into gold coins and neither did Boyle. Newton’s beliefs were in fact even weirder than our author thinks. Newton was an adherent of a widespread Renaissance philosophy known as prisca sapientia.

This theory thought that humanity had been in possession of perfect knowledge of the world shortly after the creation. This knowledge had become lost over time and Newton believed that his scientific discoveries were not discoveries but rediscoveries. He also believed that alchemy was the oldest form of knowledge and that if he could discover the secrets of alchemy he could tap into that ancient source of all knowledge. Pretty bizarre, I know, but it all formed a coherent whole in Newton’s worldview. On a scientific level the Newton experts are now convinced that his belief in alchemy enabled him to develop his theory of universal gravity, which, with its action at a distance, heavily contradicted the prevailing mechanical philosophy. The Cartesian and Leibnizian mechanical philosophers criticised his theory of gravity for exactly this reason.

Our author seems to think that there is something wrong with an alchemist becoming Warden or Master of the Mint. In fact Newton’s extensive chemical knowledge, won through his alchemical experimentation over many years, enabled him to develop and to put into practice new much improved methods of assaying metals to test the purity of coins. A major win for the Royal Mint.

The closing comment about alchemy and Harry Potter is a perfect example of the author’s childish attitude, supercilious superiority. This attitude is displayed to the full in his paragraphs about Tycho Brahe, entitled “Tycho Brahe made everyone believe he was a sorcerer”.

Tycho Brahe (1546-1601) created his own model of the universe and, though he didn’t get things quite right, helped advance astronomy and catalogued more than 1,000 stars. He also convinced everyone he was a sorcerer.

He did so from the unique perch of his private sorcerer’s island, Hveen (today known in English as Ven). Fantastically wealthy, Brahe built multiple observatories there, had a squad of astronomical assistants, and he used tiny automata (robots) to convince the locals he had magic powers. It didn’t hurt that he partied hard, had his nose partly sliced off in a duel and got his pet moose drunk at parties.

But Tycho didn’t just hoodwink the public into believing he was magical — he believed it too. He publically lectured against anyone who believed astrology was fake, and he also believed alchemy was the future for mystical discoveries. Brahe even became so synonymous with magic that an entire calendar of magical days was made in his honor (and his name was slapped on to give it magical credibility).

This is a bizarre mixture of half true facts and fairy stories. Tycho only catalogued 700 stars but added 300 more from the Ptolemaic star catalogue to bring his own up to 1000. He did nothing at all to convince anyone that he was a sorcerer. The island of Hven was his fief, awarded to him by the Danish King as his birth right as a highborn aristocrat and to call it a sorcerer’s island is not only wrong but also childish. He only built two observatories, one in his mansion house Uraniborg and the other a sunken observatory in the grounds called Stjerneborg. The story about the automata is a myth created by Pierre Gassendi in his biography of Tycho. The nose and moose stories are actually irrelevancies to the subject under discussion along the lines of, if I show that Tycho was weird then people are more likely to believe the rest of the shit that I’m dishing up.

Once again we have a very fundamental category error. Tycho was a practicing astrologer and a Paracelsian pharmacist neither of which activities is magic. Tycho held an oration at the beginning of a guest lecture course on astronomy that he held at the University of Copenhagen defending the validity of astrology, a not unusual presentation in that age. Rheticus’ public oration on being appointed professor for mathematics in Wittenberg was on the same subject. Tycho an adherent of the Renaissance microcosmos/macrocosmos philosophy, as above so below, also believed that alchemy served the same function on earth as astrology in the heavens but both were in his opinion ‘scientific’ and not mystical. Tycho’s interest in alchemy centred on his belief in and practice of Paracelsian medicine, a leading medical theory in some circles in Europe at the time and consisted mainly of research into and production of medicines.

The Magical Calendar is an engraving not a book and the author, Adam McLean, of the modern book on this object that our author links to writes the following:

“Although his name appears at the bottom right hand corner of the plate, the Magical Calendar probably has no direct connection with Tycho Brahe […] It seems most likely that the well known name of Tycho Brahe was associated with the Magical Calendar in order to gain a degree of publicity and supposed authority for the work. Certainly there is nothing in Brahe’s accepted corpus of writings of a similar nature.” [my emphasis]

Doesn’t quite say what our author wants it to say, does it?

Our author’s next selection is a truly bad example of low fruit. He presents us with Carl Linnaeus with the title “Carl Linnaeus classified magical animals like the hydra and believed in mermaids”.

Carl Linnaeus (1707-1778) imposed taxonomical order on animal and plant life. In his era, scientists were discovering all sorts of new species at a rapid clip (Linnaeus himself thought that pelicans might be a myth). That rapid pace of discovery led Linnaeus to believe, perhaps reasonably enough, that humans would soon find a host of mythological animals.

Linnaeus devoted a whole section of his landmark Systema Naturae to these strange beasts. It was called Animalia Paradoxa and included:

  • the hydra
  • the satyrus (a monkey-like man, similar to Pan in Greek mythology)
  • the phoenix (the bird that rose from the ashes)

Did Linnaeus believe in these animals? It’s hard to know, and some of Linnaeus’s defenders say he only included the animals to point out how absurd they were. In the 1730s, he became famous for debunking a hydra in Hamburg. However, we can reasonably claim that Linnaeus believed he’d found a troglodyte, was pretty confident he’d seen a unicorn horn, and was very excited at the chance to find a mermaid.

Whatever the motivation, Linnaeus wasn’t alone in believing in bizarre, vaguely magical animals. Gottfried Leibniz managed to help found calculus, yet he still wanted to fill a museum with weird (and imaginary) animals like the myrmecoleon (some sort of ant-lion).

The tone of this whole section is concerned with how superior our author is in comparison with the poor benighted Linnaeus; the heavy sent of mockery cannot be overlooked. He gives no consideration to the time in which Linnaeus was working and writing. He also appears to have left his own theme, as there is nothing ‘magical’ about the things he lists Linnaeus as having done.

Linnaeus lived and worked in the eighteenth century there was no Internet, no telephones, no telegraph, not even a reliable let alone universal postal system; a letter to South America, for example, would probably take months to arrive at its destination and quite possibly might not arrive at all. Linnaeus lived all of his life in Northern Europe and was dependent on the reports of others for descriptions of non-European species of plants and animals. If he got no chance to view one personally then a tiger was just as much a mythical animal as a manticore and he had no chance of proving the real existence of the one or the other. What we have here is an eighteenth century natural historian carefully classifying all the plants and animals that are known to him through multiple written sources. It’s worth noting that Linnaeus places those mythical creatures that he classifies into a separate category that he names Paradoxa the Greek pardoxon meaning contrary to accepted opinion, i.e. dodgy. Systema Naturae went through many editions and in the later ones this category was left out. Only one real animal was included in Paradoxa, the pelican, which given the fact that travellers tales described the pelican as cutting its own breast to feed its children was not an irrational decision. None of the mythical animals was included in a category with real animals. What we have here is careful rational scientific behaviour not magical thinking.

Linnaeus included humans as primates, which of course caused a controversy in the eighteenth century. He also included two other species in the genus homo, Homo troglodytes based on the accounts of Jacob Bontius and Homo lar based on other reports. He asked the Swedish East India Company to look for confirming evidence of the existence of Homo troglodytes, which they couldn’t deliver and Homo lar was later categorised as a gibbon, again a good natural historian doing his work. Belief in unicorns, some form of single horned horse, based on the existence of narwhal tusks was still very widespread in the eighteenth century, so to try and ridicule Linnaeus or this is pathetic. The same applies to mermaids.

The author’s attempt to besmirch Leibniz is really clutching at straws. What the hell is ‘managed to help invent calculus’ supposed to mean? That’s not exactly the usual way of talking about one of the greatest mathematical achievements of the seventeenth century. Curiosity cabinets and natural history collections played a central role in scientific activities throughout the sixteenth, seventeenth and eighteenth centuries, one of the largest, that of Hans Sloane, forming the basis of the British museum after Sloane’s death. Leibniz’ Drôle de Pensée, amusing thought, was to extend the curiosity cabinet into a much larger public exhibition space with active displays and machines alongside the passive objects displaying the full spectrum of science, technology and medicine, Science Museum anyone? That his long list of potential exhibits contains one mythical animal hardly makes this something to deride.

Our author’s fifth genius is, as would be expected, Paracelsus who apparently “loved natural magic and himself”.

Paracelsus (1493-1541) did a lot when he was alive, including basically inventing toxicology and naming zinc. But when he wasn’t revolutionizing scientific methods and naming metals, he was a big fan of magical things.

Born as Philippus Aureolus Theophrastus Bombastus von Hohenheim, he renamed himself Paracelsus, both because it was shorter and it literally meant he was “better than Celsus,” a first century Roman medical researcher (in Paracelsus’s defense, he may have been renamed by his biggest fans). Paracelsus wrote that from an early age the “transmutation of metals” was his obsession, and he pursued it with vigor as an adult.

When he wasn’t traveling the world performing surgeries, he tried to utilize “natural magic” to help patients. He was quoted as saying “magic is a great secret wisdom,” and while his understanding of natural magic occasionally lent itself to scientific inquiry, he also believed that “the soul strongly desires sulphur.” As the scientist on this list closest in time to Aristotle, it makes sense that Paracelsus would indulge in magic and the occult.

In his defense, that belief in magic was grounded in a commitment to inquiry: Paracelsus thought magic was just science that wasn’t understood yet. In a way, that unites all the scientists on this list, who pursued new knowledge even when it meant looking in some very unusual places.

The claim that Paracelsus basically invented toxicology, although not original to our author (who I doubt has any original thoughts), is historically highly dubious as poisons have been studied extensively since antiquity and it is rather strangely based on the legendary Paracelsus quote Dosis sola venenum facit, the dose makes the poison. Paracelsus was not born Philippus Aureolus Theophrastus Bombastus von Hohenheim, I refer the reader to my earlier post on the subject of his name.

The rest of the paragraphs on Paracelsus are a confused mess of unrelated claims picked at random from other peoples writings and doesn’t earn the right to be analysed so I won’t. I would ask the author why, having suddenly introduced the term, he doesn’t actually explain what natural magic is or was. Possibly the worst single sentence in the whole sorry mess that is this article is, As the scientist on this list closest in time to Aristotle, it makes sense that Paracelsus would indulge in magic and the occult. Anybody who actually knew anything about either Paracelsus or Aristotle could not conceive of writing this sentence, even as a parody.

Returning to my initial criticism of this apology for a historical article, astrology and alchemy are not magic if dealing academically and historically with these disciplines and because he introduces it at the end ‘natural magic’ is not magic as it is generally understood either. As often the case I find it fascinating that people who quite literally don’t know what they’re talking about think that it’s OK to write an article about the history of science on a widely read popular website. If they were to write about something popular, such as football or cars, on the same level no editor in the world would allow them to publish it, so why do they treat the history of science with such disrespect?





Filed under History of Alchemy, History of Astrology, Myths of Science, Renaissance Science

The specialist in causing pain.

I suppose I ought to rebrand Galileo Galilei as ‘The Gift that keeps on Giving”! The comment is of course directed at all the idiots who think they need to present their image of Galileo to the world, rather than at the 16th- and 17th-century Tuscan artist-engineer himself. As long as there is a GG Super Star I will never be short of material for this blog, although it might become a little bit monotone with time. The most recent offender is Michael Vagg on The Conversation in an article entitled Four things we should teach every kid about Galileo. Before looking at Mr Vagg’s contribution to the Galileo debate I want to waste a few words on The Conversation, which describes itself as follows:

The Conversation is a collaboration between editors and academics to provide informed news analysis and commentary that’s free to read and republish.

Its banner head also has the subtitle “Academic rigour, journalistic flair”. Apparently, at least judging by Mr Vagg’s article, this proud boast doesn’t apply when it comes to the history of science.

Mr Vagg, Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health, apparently recently attended a conference in Florence and took time out to visit the Museo Galileo, a laudable way to spend his free time. He tells us he bought three books from the gift shop one of which was Galileo: Antichrist, which he describes, a serious scholarly attempt to look behind the obvious motives for his trial and punishment by the Church to some of the contemporary nuances, going on to say that he highly recommend[s] it, if you’re a Galileo freak and historical conspiracy theory enthusiast like me. Unfortunately Mr Vagg is mistaken in his assessment of this book. Of all the more recent publication about Galileo, provoked by the four hundred and fiftieth anniversary of his birth, Galileo: Antichrist is one of the worst. A popular biography written by Michael White it turns back the clock by about two hundred years and presents a vision of Galileo’s life and work that would be comfortably at home at the beginning of the nineteenth century, full of myths and distortion and not to be recommended to anybody who serious wants to know the historical truth about Galileo Galilei. Mr Vagg seems to have largely based his “four truths” on Whites totally distorted view of Galileo and his achievements.

His first “truth is entitled “He got rid of Aristotle from science” and I reproduce the whole of his section to this theme, which is to put it mildly horrendous. His first paragraph reads as follows:

Before Galileo, science (known then as natural philosophy) was based almost entirely on the writings of Aristotle. St. Thomas Aquinas enshrined a huge amount of Aristotle’s teachings about the natural world as Church-approved dogma without any empirical basis. Until the Renaissance, virtually nobody in Europe or anywhere else apart from Arabic geniuses like Ibn Sina and Ibn Rushd advanced science by paying attention to the real world. They just looked up what Aristotle had to say and left it at that, even if what they observed was at odds with what they read.

One of my favourite historians of medieval science, David C Lindberg, died a couple of weeks ago and he would be spinning in his grave if he knew of this travesty of his disciple, which reads like something from the beginning of the nineteenth century or even from the Renaissance. It was Renaissance scholars who were initially responsible for this wholly false picture of medieval science. They created the myth that the golden age of antiquity created a cornucopia of knowledge that got lost with the collapse of the Roman Empire and that they were responsible for the rebirth (renaissance) of this knowledge, freeing Europe from the dark ignorance of the intervening period, which they termed the Middle Ages. This myth was perpetuated right up into the nineteenth century, when the French physicist and historian of science, Pierre Duhem, became the first person to challenge it. Throughout the twentieth century a series of brilliant historians of science, including such people as Marshall Clagett, Alistair Crombie, John Murdoch, Edward Grant, the afore mentioned David Lindberg and others, completely dismantled this myth showing that European medieval scholars made significant contribution to the evolution of science; contribution on which people such as Galileo built their own contributions.

To give one example that is very relevant to Galileo and his theories of motion called revolutionary by Vagg. Even Aristotle was aware of the fact that his laws of motion were anything but satisfactory and the first person to subject them to serious scrutiny was John Philoponus in the sixth century CE, who developed the impetus theory, which was developed further by Arabic scholars in the twelfth and thirteenth centuries and by Buridan in Europe in the fourteenth century. Galileo well aware of this work adopted the impetus theory early in his own work on kinetics before moving on to an incorrect form of the theory of inertia. (Galileo still considered natural motion to be circular, not linear, an Aristotelian concept!) In the fourteenth century the so-called Oxford Calculatores of Merton College developed the mathematical mean speed theory, which is to all intents and purposes Galileo’s law of fall. One of the so-called Paris physicists Nicolas Oresme produced a geometrical proof of this theory, in the form of a graph, which is identical to the proof given by Galileo for his law of fall in his Discorsi more than three hundred and fifty years later. It was also the invention of spectacles in the late thirteenth century that would eventually lead to the invention of the telescope, the instrument that would make Galileo famous. Far from being scientifically sterile the Middle Ages was the very fertile seed bed in which Galileo’s own scientific ideas grew to maturity.

In his second paragraph in this section Vagg dished up the following:

Galileo did more than anyone else to rid natural philosophy of its reliance on the authority of Aristotle, replacing it with an empirical and mathematical method. Deciding scientific knowledge by scholarly argument rather than doing experiments seems bizarre to us now. Galileo showed again and again that mathematical models could yield results that were reproducible by anyone else and disproved Aristotle’s observations. Eventually, the successes of the new way of doing natural philosophy were too overwhelming to ignore. The Aristotelians slunk off to find other occupations. Galileo showed irrefutably that you couldn’t do science by magisterial authority alone. Your results had to stand up to scrutiny in the real world.

As I explained in an earlier post, that earned me my reputation as a Galileo deflator, Johannes Kepler, Thomas Harriot, Christoph Scheiner, William Gilbert, Christoph Clavius, Francoise Vieta, Isaac Beeckman and Simon Stevin, all roughly contemporaries of Galileo, all did at least as much, and some of them more than, Galileo in establishing the ‘new’ experimental mathematics based science in the early seventeenth century and the myth of Galileo as the great Aristotle slaying champion is one that needs to be firmly stamped on. Also modern history of science has shown that many aspects of Aristotle’s philosophy continued to exercise a strong influence on the development of science well into the seventeenth century long passed the death of Galileo.

Vagg’s second point is actually a very good one and would have been praise worthy if he hadn’t gone on to spoil it in the detail. His title is, “He was not the prototype of a misunderstood lone genius”. This is very correct and in fact the misunderstood lone genius is not only a myth but also a chimera, there has never been one. This is in fact an important point that should indeed be taught to every school kid as part of their science courses, however Vagg goes on to spoil it by presenting a totally mythical picture of Galileo.

Galileo was very much not a lone genius. He relied on Guidobaldo del Monte and Christopher Clavius to get both of his jobs as professor of mathematics and early in his career he relied on the transcript of the lectures from the Collegio Romano to deliver his own lectures. As a young researcher he spend long periods brainstorming with del Monte and Paolo Sarpi over a wide range of topics. Sometimes it is not possible to tell if the ideas he made public really were his own or ones borrowed from one or other of those intellectual partners. For his telescope and instrument making he employed and relied heavily on a technician, who usually doesn’t get the credit he deserves. For his excursions into applied science and technology in the arsenal in Venice he relied heavily on the guidance of master ship builders. Later in life following his overnight fame he relied on his fellow members of the Accademia dei Licei as sounding boards for his ideas and those lynx-eyed friends also prepared his works for publication and published them. Even after his fall, under house arrest, Galileo had students and his son helping with his scientific work. Galileo was for most of his life part of a network of like-minded friends and assistants, however this is not the story that Vagg presents.

When he published the Starry Messenger to announce his discovery of the moons of Jupiter with his new telescope, he not only sent out copies of his books to his colleagues, but also sent them better telescopes than the ones they had!

I suggest Vagg should read Mario Biagioli’s Galileo Courtier and Galileo’s Instruments of Credit. Galileo did not send copies of the Sidereus Nuncius or telescopes to his colleagues; he sent them to civil and religious potentates who could help him in his ambitions to climb the social greasy pole. Despite requests for a telescope Kepler had to wait till a passing aristocrat graciously let him borrow one for a couple of hours to see the new astronomical discoveries. Galileo ignored Kepler’s friendly collegial overtures until he, Kepler, became the only person to support without confirmation those discoveries, publishing Kepler’s letter without his knowledge or permission. Later he ridiculed Kepler’s groundbreaking book on the optics of the telescope as unreadable. He ignored Kepler’s work on heliocentricity when writing the Dialogo, despite the fact that it was the best available on the subject, whilst ridiculing Tycho’s work. When he and Scheiner both discovered the sunspots he accused Scheiner, unjustifiably, of plagiarism and then published some of Scheiner’s results in the Dialogo as his own. In the dispute over the nature of comets with Grassi he viciously attacked Grassi exposing him to public ridicule with malicious polemic, although scientifically Grassi was right and he, Galileo, was wrong. As he and Marius both independently discovered the moons of Jupiter he accused Marius of plagiarism, a charge that stuck ruining Marius’ reputation until it was restored at the beginning of the twentieth century.

This is the man who Vagg claims was “a practising believer in developing a scientific consensus”. Galileo did not believe in scientific consensus, he was a man with a monstrous ego who was right and anybody who disagreed with him got mauled viciously for his troubles. Vagg writes rather pathetically:

He was revered in his lifetime by every natural philosopher of note, although some of ones he personally insulted were somewhat grudging in their admiration.

He was justifiably intensely disliked and despised by quite a few natural philosophers of note. Vagg does however point out that Galileo was not perfect:

He could, of course, also be spectacularly wrong. Nobody remembers his views on comets and the causes of tides, which were two of the biggest contemporary scientific controversies he weighed into. It should also be pointed out that these were the two most prominent examples where Galileo was being particularly stubborn in holding out against the prevailing tide of opinion.

A lot of historians of science remember his views on comets and the causes of tides very well indeed.

The title of Vagg’s next section is also correct, “He was genuinely interdisciplinary” but then again so were all his contemporaries, our concept of the single disciple specialist or expert didn’t exist in the Renaissance. However in his description of Galileo’s multifarious activities Vagg makes several serious blunders. He tells us:

While his astronomical work may seem like it had no practical applications, it led him to develop a way of measuring longitude at sea that was not surpassed until more than 150 years later.

Galileo did conceive a method of using the eclipses of the moons of Jupiter by the planet, as they orbited it, as a clock with which to determine longitude. However, he never succeeded in determining the orbits accurately enough for this purpose, a task first completed by Cassini many decades later. Also more importantly, although this method could be and was used successfully on land, for cartographical purposes, it could never be used at sea, a ship being far too unstable to make the necessary highly accurate astronomical telescopic observations. It is of historical interest that the chronometer method and the lunar distance method of determining longitude, which were the methods that would eventually solve the problem, were both proposed long before Galileo was even born. Next up we get informed that:

He translated his knowledge of the abstract mathematical minutiae of optics into building much better telescopes than anyone else had. He extended this theory to conceive and design the microscope as well.

With the exception of Yaakov Zik, almost all historians of the telescope think that Galileo had very little knowledge of geometrical optics and in fact used his skills as an instrument maker to develop his telescopes by simple trial and error. Although no single inventor of the microscope is known to us, as I’ve already written in an earlier post, Galileo was almost certainly one of the inventors of the microscope an instrument that he, according to his own testimony, discovered by accident when he put one of his telescopes to his eye the wrong way round. He then improved on this accidental discovery, again not by using the theory of geometrical optics, but by trial and error.

The military compass described by Vagg was in fact invented by del Monte and only manufactured and sold along with instruction courses in its use by Galileo as an additional source of income. Vagg closes out this section with a final error:

In the final year of his life, having gone totally blind, Galileo conceived and dictated the design for a clock escapement which was very similar to the one used by Huygens to construct the first pendulum clock a couple of decades later.

The pendulum clock escapement conceived by Galileo but never really realised was substantially different to the one developed by Huygens decades later.

Vagg’s fourth point worthy of the attention of school kids is, “He stood up for the philosophy of science”. Whilst this statement does contain more than a grain of truth Vagg again succeeds in on presenting a largely false historical picture to illustrate it.

Despite using maths that is now taught in high school and equipment that would embarrass a 21st century toy shop owner, Galileo utterly changed the way his contemporaries saw themselves in the universe. Educated citizens of his time had a sophisticated explanation of the world and the heavens, but it was based on dogma and supposition to a degree that is very hard to comprehend today. By making arguments that were based on reasoning, mathematics and experimental verification, he was consistently and obviously successful with many of his predictions. This opened his contemporaries’ eyes to the extraordinary possibilities on offer with knowledge gained by the scientific method.

This paragraph contains a complete misrepresentation of the general state of science at the time of Galileo. Those things that Vagg praises Galileo for had been gaining ground strongly throughout European science for more than a century before Galileo made any contributions to the topic at all. Since the High Middle Ages people had been making contributions to science based on reasoning, mathematics and experimental verification. Galileo made an important contribution to this trend but he didn’t start it. It should also not be forgotten that Galileo used this methodology when it suited him but also resorted to polemic and brow beating when it suited him better. His dispute with Grassi on the nature of comets is a good example of this behaviour.

Observing that Venus had phases like the moon, and having plotted the orbits of the Galilean satellites meticulously, he could join the dots conceptually, and followed the chain of reasoning to the end. The results were not what he was originally looking to discover, but he just couldn’t turn his back on his data. Earth was demoted from the fixed centre of the medieval universe to just another planet orbiting the sun. He strenuously sought ways to avoid provoking the Church (he was a devout believer right to the end) but he could not stop progressing and disseminating his research, despite those who told him it was safer to pull his head in.

Maybe I’m misreading this but it appears to me that Vagg is implying that Galileo initiated the heliocentric model of the cosmos, has he never heard of Copernicus or Kepler? Also, as I’ve written in detail in other posts, the telescopic discoveries made by Galileo, Scheiner, Marius, Harriot and others, whilst refuting a pure Ptolemaic geocentric model, were a long way from confirming a heliocentric model and were also conform with various Tychonic and semi-Tychonic models. These facts alone constitute an important lesson in how science evolves.

“He strenuously sought ways to avoid provoking the Church” is another mythical statement from Vagg. One of Galileo’s major problems was that his mega ego prevented him from seeing when he was provoking those that he attacked, mocked, contradicted. Convinced of his own innate superiority he just blundered from one provocation to the next. A seemingly trivial point, but actually not so trivial, is the claim “he was a devout believer right to the end” this, or something similar is a standard part, of the Galileo mythology trotted out by almost everyone who has put pen to paper or fingers to keyboard to write about the man. However, David Wootton in his biography, Galileo: Watcher of the Skies, a genuinely ‘serious scholarly’ book, argues very convincingly that far from being the devout Catholic of popular science literature, Galileo was in fact a very lax Catholic. This of course rather spoils the common plaint, ‘he was a true believer and still they punished him’ of the ‘Galileo was a martyr for science’ fan club.

He insisted that dependable, reproducible scientific results should trump religious dogma or non-empirical philosophical ideas any day of the week. He paid a price for his abrasiveness, but he should not be remembered just for the events that blighted his later years. His persecution and house arrest by the Vatican were not inevitable, but threw into sharp focus the clash of his era between a recognisably modern science-based worldview and the medieval superstition of authoritarian belief systems. Somebody had to be the first to point out the Emperor’s new clothes.

The last couple of lines of the previous paragraph and this one refer, of course, to the publication of Galileo’s Dialogo and his subsequent trial by the Inquisition of Rome. Unfortunately Galileo’s masterpiece didn’t rely on ‘dependable, reproducible scientific results’ because they didn’t exist for the heliocentric theory, instead he used polemic and sleight of hand to confuse, bamboozle and confound his opponents hoping that nobody would notice how thin his scientific arguments actually were. The whole book was of course structured around the fourth and final section, Galileo’s theory of the tides, (which Vagg so casually swept aside above) that he, in a strange fit of blind arrogance, believed to be the missing empirical proof that the earth moved, the lack of such proof being the strongest scientific argument against the heliocentric hypothesis. Originally Galileo wanted to give the whole book the title Theory of the Tides but the Church censor wouldn’t permit it, so he chose the title that has gone down in history instead. Galileo thought that this theory was his all-winning trump, whereas it was in reality a busted flush, as any half thinking person could have told him. Galileo did not write the book in opposition to the Church but with the Pope’s explicit permission. However Urban, not unreasonably, commissioned him to write a book presenting the various cosmological/astronomical models of the cosmos factually and without favour or prejudice. If Galileo had written a book presenting the arguments for and against geocentricity, heliocentricity and helio-geocentricty (he completely ignored the latter, although at the time he wrote it was the model that best fit the known scientific facts) fairly and honestly, we probably wouldn’t waste so much time discussing the conflict between him and the Church because there wouldn’t have been one. Instead he wrote a book, which was an undisguised polemic in favour of heliocentricity hoping nobody would notice the lack of real empirical evidence and finished it off by gratuitously insulting the Pope. Wow really clever GG! The clash between worldviews that Vagg so pathetically evokes at the end of this paragraph exists only in his fantasy and not in the historical reality. The clash between Galileo and Urban was on a very personal level and in no way reflects a general clash between the then theological worldview and, to quote Vagg, a recognisably modern science-based worldview. This supposed clash is a myth created in the nineteenth century that has long been demolished by historians of science but people like Vagg prefer to keep peddling the myths rather than taking the trouble to learn the truth. Possible the worst piece of claptrap in Vagg’s ahistorical article is his closing sentence.

I am however eternally grateful for the effect his life’s work had on the philosophy of science. Development of the Enlightenment values that underpin our society would not have been possible without the seismic burst of rationalism that Galileo unleashed from his villa in Northern Italy 500 years ago.

Wow Mr Vagg, you have set a new high water mark in ahistorical mythical hagiography. At least it will provide employment for lots of historians rewriting all those history books that missed out on GG’s vital role in the Enlightenment. Mr Vagg, pain specialist, your pathetic attempts to write history of science, a subject you very obviously know nothing about, has certainly caused this historian of science a great deal of pain indeed.



Filed under History of Astronomy, History of science, Myths of Science, Renaissance Science

The Simon Marius Anniversary Celebrations 2014 have been a great success

On the 8 January 1610 the Ansbach court astronomer Simon Marius first observed the four largest moons of Jupiter just one day later than Galileo Galilei, although he would delay four years before publishing the results of his observations unlike his Tuscan rival, who famously rushed into print with his amazing discovery. It seemed somehow appropriate to post this press release here on this anniversary of that, for Marius, momentous event.

Press Release – The Simon Marius Anniversary Celebrations 2014 have been a great success.

The initiators of the ‘The Simon Marius Anniversary Celebrations 2014’ can look back over a very eventful year. More than 60 lectures and exhibitions corrected the public image of the margravial court astronomer both at home and abroad, and more than 200 articles appeared in newspapers, magazines, and other media. Motivation was the publication of Simon Marius’ magnum opus Mundus Iovialis (The World of Jupiter) four hundred years ago in 1614.

The first high point of these activities was the launching of the Marius-Portal,, in The State Archives in Nürnberg. This Internet site contains a bibliography, with 28 menu languages, of all the publications by or about Simon Marius (1573-1624), who discovered the four largest Jupiter moons at the same time but independently of Galileo Galilei in 1610. A substantial number of these publications have been digitised and can – where legally permitted – be viewed directly. The medium-term aim is to create a virtual ‘Collected Works’.

The designation of an asteroid by the International Astronomical Union was very pleasing. The asteroid “(7984) Marius” is about 10 km in diameter and is situated in the so-called main belt between Mars and Jupiter. It orbits the sun once every 4.27 years and travels at a speed of 7.57 km/s.

The final high point was the conference “Simon Marius und seine Zeit” (Simon Marius and his Times), which focused on the results of his researches. The conference report will appear in 2015.

Galileo Galilei had accused the margravial court astronomer of plagiarism, however at the beginning of the 20th century he was rehabilitated and in 2014 Simon Marius was honoured in particular in Southern Germany but also in the Cosmonaut Museum in Moscow and in the USA. Galileo and Marius discovered the four largest Jupiter moons in January 1610, but Marius first published his results four years later than his Italian colleague. Today we know that in the 17th century Marius was an astronomer at the highest European levels.

The ‘The Simon Marius Anniversary Celebrations 2014’ was initiated by the Nürnberger Astronomischen Gesellschaft (Nürnberger Astronomical Society) and will be set forth by the Simon Marius Gesellschaft (Simon Marius Society), which was founded at the end of December 2014.

Any readers who wish to do so are cordially invited to become a normal or corresponding member of the Simon Marius Society, membership is free.


Filed under History of Astronomy, Local Heroes, Renaissance Science