Category Archives: History of science

Giambattista della Porta the most polymathic of all Renaissance polymaths?

Giambattista della Porta (1535(?)–1615) is well known to historians of Renaissance science but for the general public he remains a largely unknown figure. If he is known at all,  he is often written off as an occultist, because of the title of his most well known work Magia Naturalis. In fact in the late sixteenth and early seventeenth centuries he was a highly respected and influential member of the Italian Renaissance scientific community. Although he wrote and published profusely over a wide range of scientific and related topics he made no really major discoveries and produced no major inventions and unlike his contemporaries, Kepler and Galileo, who were both well acquainted with his work, he has been largely forgotten.

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Giambattista della Porta Source: Wikimedia Commons

Giambattista Della Porta were born at Vico Equense, Near Naples, probably sometime in 1535 (he created the confusion about his birth date), the third of four sons of the nobleman Nardo Antonio dell Porta of whom three survived childhood.  His parental home resembled an intellectual salon where the boys were continually exposed to and educated by visiting philosophers, mathematicians, poets and musicians. Their education was completed by private tutors, who also taught the boys the attributes of a gentleman, dancing, riding, skilled performance in tournaments and games and how to dress well. Della Porta never attended university but enjoyed life as a well educated polymathic, gentleman of leisure. If he can be considered to have had a profession, then it is that of a dramatist, he wrote more than twenty theatrical works, but it is his extensive activities in the sciences that interest us here.

Already in 1558, at the age of 23, he published the fist version of his most well known work, the Magia Naturalis in four books, a sort of encyclopaedia of the Renaissance sciences. From the beginning it was a bestseller running to five editions in Latin within the first ten years with translations into Italian (1560), French (1565), Dutch (1566) and English (1658). A vastly expanded version in twenty books was published in 1589. This final version covers a wide range of topics:

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Source: Wikimedia Commons

Book 1: Of the Causes of Wonderful Things Book 2: Of the Generation of Animals Book 3: Of the Production of New Plants Book 4: Of Increasing Household-Stuff Book 5: Of Changing Metals Book 6: Of Counterfeiting Glorious StonesBook 7: Of the Wonders of the Load-Stone Book 8: Of Physical Experiments Book 9: Of Beautifying Women Book 10: Of Distillation Book 11: Of Perfuming Book 12: Of Artificial Fires Book 13: Of Tempering Steel Book 14: Of CookeryBook 15: Of Fishing, Fowling, Hunting, etc. Book 16: Of Invisible Writing Book 17: Of Strange Glasses Book 18: Of Static Experiments Book 19: Of Pneumatic Experiment Book 20: Of the Chaos

The contents range from fairly banal parlour tricks, over engineering, experimental science, horticulture and husbandry to every day things. At the very beginning della Porta is very careful to explain what exactly he mean by the term natural magic:

There are two sorts of Magick; the one is infamous, and unhappy, because it has to do with foul Spirits and consists of incantations and wicked curiosity; and this is called Socery; an art which all learned and good men detest; neither is it able to yield an truth of reason or nature, but stands merely upon fancies and imaginations, such as vanish presently away, and leave nothing behind them; as Jamblicus writes in his book concerning the mysteries of the Egyptians. The other Magick is natural; which all excellent wise men do admit and embrace, and worship with great applause; neither is there any thing more highly esteemed, or better thought of, by men of learning. The most noble Philosophers that ever were, Pythagorus, Empedocles, Democritus, and Plato forsook their own countries, and lived abroad as exiles and banished men, rather than as strangers; and all to search out and to attain this knowledge; and when they came home again, this was the Science which they professed, and this they esteemed a profound mystery. They that have been most skillful in dark and hidden points of learning, do call this knowledge the very highest point, and the perfection’s of Natural Sciences; inasmuch that if they could find out or devise amongst all Natural Sciences, any one thing more excellent or more wonderful then another, that they would still call by the name of  Magick. Others have named it the practical part of natural Philosophy, which produces her effects by the mutual and fit application of one natural thing unto another.

The association of Magick with natural philosophy is continued in della Porta’s definition of the Magician:

This is what is required to instruct a Magician, both what he must know, and what he must observe; that being sufficiently instructed in every way, he may bring very strange and wonderful things to us. Seeing Magick, as we showed before, as a practical part of natural Philosophy, it behooves a Magician and one that aspires to the dignity of the profession, to be an exact and very perfect Philosopher.

Despite the very diverse nature of the Magia Naturalis it does contain elements of genuine experimental science. For example, it contains the first experimental disproof of the widely held medieval belief that garlic disables magnets. He also experimented with the cooling properties of dissolving nitre in water. As described here by Andrea Sella (@SellaTheChemist)

As well as the Magia Naturalis della Porta wrote and published a large number of monographs on a very wide range of topics. Cryptography was a popular topic in Renaissance Europe, the most famous book being Johannes Trithemius’ Poligraphia, della Porta published his De Furtivis Literarum Notis (1563), which contain innovative cryptographical ideas.

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In 1586 he published a work on physiognomy De humana physiognomonia libri IIII,

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From De humana physiognomonia, 1586 Source: Wikimedia Commons

which was still being referenced in the nineteenth century, two years later a book on phytonomy (the science of the origin and growth of plants), Phytognomonica, which contains the first observations on fungal spores.

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Phytognomonica, 1588 Source: Wikimedia Commons

These two books confirm della Porta’s adherence to the Renaissance doctrine of signatures. This theory claimed that it was possible to determine the nature of things based on their external appearances.

This was by no means the limit to della Porta’s publishing activities. He also wrote an agricultural encyclopaedia, separate volumes on various fruit bearing trees, books on mathematics, astronomy, meteorology, military engineering, distillation and in 1589 a book on optics, his De refractione optics. We shall return to the latter.

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This incredible literary outpouring was just part of his scientific activity, in about 1560 he founded an academic society, Accademia dei Segreti (Academia Secratorum Naturae), the Academy of the Secrets of Nature, which is considered to be the earliest scientific society. The academy met regularly in della Porta’s home and membership was open to all but to become a member one had to present a new secret of nature that one had discovered. We know what some of those new secrets were as della Porta included them in the twenty volume version of his Magia Naturalis. In 1578 della Porta was summoned to Rome and investigated by the Pope. We do not know the exact grounds for this summons but he was forced to shut down his academy on suspicion of sorcery. This is to a certain extent ironic because della Porta was very careful in all his writing to avoid controversial topics particularly religious ones.

Although it was shut down the Accademia dei Segreti, would later have a major influence on another, much more renowned, early scientific academy, Federico Cesi’s Accademia dei Lincei. Cesi was a huge admirer of della Porta and as a young man travelled to Naples to visit the older natural philosopher. On his return home he founded his own academy, whose name was inspired by a line from the preface of the Magia Naturalis:

… with lynx like eyes, examining those things which manifest themselves, so that having observed them, he may zealously use them.

In 1610 della Porta became the fifth member of the Accademia dei Lincei, one year before Galileo.

Another important aspect of Renaissance science was the establishment of private natural philosophical museums also known as Wunderkammer, or cabinets of curiosity. Della Porta had, as to be expected, a particular fine cabinet of curiosity that would influence others to create their own, the Jesuit Athanasius Kircher for example.

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Fold-out engraving from Ferrante Imperato’s Dell’Historia Naturale (Naples 1599), the earliest illustration of a natural history cabinet Source: Wikimedia Commons

Della Porta made minor contribution to the advance of science and engineering over a wide range of disciplines but I first ran into della Porta in the context of the history of optics and it his association with this history that I want to look at in somewhat more detail. The early seventeenth century saw both a significant turn in the theory of optics and independently of that the invention of the telescope, an instrument that would go one to revolutionise astronomy, della Porta played a minor roll in both of these things.

The invention of the telescope, by Hans Lipperhey, first became public in September 1608 and the role it would play in the future of astronomy became explosively obvious when Galileo published his Sidereus Nuncius in March 1610. Already in August 1609 della Porta wrote a letter to Federico Cesi claiming to have invented the telescope, he wrote:

I have seen the secret use of the eyeglass and it’s a load of balls [coglionaria] in any case it is taken from book 9 of my De Refractione.[1]

Here della Porta’s memory is faulty, he is after all over seventy years old, what he is referring to is not in the De Refractione but rather in Chapter 10 of Book 17 of Magia Naturalis (1589). Here we find the following suggestive description:

Concave Lenticulars will make one see most clearly things that are afar off.  But Convexes, things near at hand.  So you may use them as your sight requires.  With a Concave Lenticulars you shall see small things afar off very clearly.  With a Convex Lenticular, things nearer to be greater, but more obscurely.  If you know how to fit them both together, you shall see both things afar off, and things near hand, both greater and clearly.  I have much helped some of my friends, who saw things afar off, weakly, and what was near, confusedly, that they might see all things clearly.  If you will, you may.

The lens combination that della Porta describes here is indeed that of the Dutch or Galilean telescope but as van Helden say, and I agree with him, he is here describing some form of spectacles but not a telescope. Kepler, however, who owned a copy of Magia Naturalis credits him with being the inventor of the telescope in his Dissertatio cum Nuncio Sidereo (Conversation with the Starry Messenger) (1610), where he wrote that a recent Dutch invention had been made public years earlier in Magia Naturalis. In 1641 Pierre Gassendi stated that the actual invention had been made by chance by Metius [Jacob Metius (after 1571–1628), who applied for a patent for a telescope two weeks later than Lipperhey] the idea for a similar one had been published years earlier by della Porta.

Later della Porta would graciously admit that his fellow Lynx, Galileo, had achieved much more with his telescope that he, della Porta, could have ever have hoped to do, whilst not abandoning his claim to having first conceived of the telescope.

Della Porta also played a small role in the history of the camera obscura, describing the improvement to the image obtained by placing convex lens into the pinhole, something probably first suggested by Gerolamo Cardano. He also suggested, this time as the first to do so, using a concave mirror to project the image onto a sheet of paper to facilitate drawing it. The popularity of the Magia Naturalis did much to spread knowledge of the camera obscura and its utility as a drawing instrument. Interestingly della Porta compared his camera obscura with the human eye but, unlike Kepler, failed to make the connection that the lens focuses the image on the retina. He continued to believe like everybody before him that the image in perceived in the lens itself.

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First published picture of camera obscura in Gemma Frisius’ 1545 book De Radio Astronomica et Geometrica Source: Wikimedia Commons

Della Porta’s role in the turn in the theory of optics is less disputed but not so widely discussed.  Ancient Greek optics was almost exclusively about theories of vision and when taken up and developed in the Islamic Middle Ages this too remained the emphasis. Ibn al-Haytham in his work on optics showed that one could combine an intromission theory of vision with the geometric optics of Euclid, Hero and Ptolemaeus, who had all propagated an extramission theory of vision. This was a major development in the history of optics. In the thirteenth century Robert Grosseteste introduced optics as a central element in both his vision of science and his theology, which led to it being established as a mathematical discipline on the medieval university. Shortly after Roger Bacon, John Peckham and Witelo introduced al-Haytham’s theories on optics into the medieval European mainstream founding what became known as the perspectivist school of optics. Strangely there were no real further developments in the theory of optics down to the end of the sixteenth century when Johannes Kepler, almost singlehandedly, turned the study of optics from one of theories of vision to one of theories of light, thereby ending the reign of the perspectivists. I say almost singlehandedly but he did have two predecessors, who made minor contributions to this turn, Francesco Maurolico (1494–1575) and della Porta.

One major flaw in the perspectivist theory was its treatment of spherical convex lenses and spherical concave mirrors, which said that the images created by them appeared at a single focus point; this is a fallacy. This flaw was in the theory from its inception in the thirteenth century and remained unchecked and uncorrected all the way down to the end of the sixteenth century. The fact that the don’t create their images at a single focal point is, of course, the cause of spherical aberration, something that would plague the construction of telescopes and microscopes well into the eighteenth century. The man who corrected this error in optical theory was della Porta.  Using a mixture of experiments and analytical light ray tracing he came very close to the correct solution an important step towards Kepler’s light ray based theory of optics.

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Della Porta’s ray tracing analysis of the reflection of a spherical concave mirror A. Mark Smith, “From Sight to Light: The Passage from Ancient to Modern Optics”, Chicago University Press, 2015 p. 349

Giambattista della Porta is an interesting example of a widespread phenomenon in the history of science. In his own times he was highly respected and regarded, throughout Europe, as a leading natural Philosopher. His books, translated into many languages, were bestsellers and that even long after his death. Johannes Kepler was a fan and Galileo disliked him because he saw him as a serious rival for the position of top dog natural philosopher, a position that Galileo very much desired for himself. However, today most people have never even heard of him and if then he is largely dismissed as a minor irrelevance or even, because of the title of his major work, as some sort of anti-science occultist. But if historians really want to understand what was going on in the scientific community of Europe in the Early Modern Period then they have to take figures like della Porta seriously and not just focus on the ‘big names’ such as Kepler and Galileo.

 

 

 

 

 

 

 

 

 

 

 

 

[1] Quoted from David Freedberg, The Eye of the Lynx: Galileo, His Friends and the Beginnings of Modern Natural History, University of Chicago Press, Chicago and London, 2002, ppb. p. 101 Albert van Helden in his The Invention of the Telescope, American Philosophical Society, Philadelphia, 1977, Reprint, 2008, translates the phrase with coglionaria as …”it’s a hoax” pp. 44-45

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Filed under History of Optics, History of science, Renaissance Science

Our medieval technological inheritance.

“Positively medieval” has become a universal put down for everything considered backward, ignorant, dirty, primitive, bigoted, intolerant or just simply stupid in our times. This is based on a false historical perspective that paints the Middle Ages as all of these things and worse. This image of the Middle Ages has its roots in the Renaissance, when Renaissance scholars saw themselves as the heirs of all that was good, noble and splendid in antiquity and the period between the fall of the Roman Empire and their own times as a sort of unspeakable black pit of ignorance and iniquity. Unfortunately, this completely false picture of the Middle Ages has been extensively propagated in popular literature, film and television.

Particularly in the film and television branch, a film or series set in the Middle Ages immediately calls for unwashed peasants herding their even filthier swine through the mire in a village consisting of thatch roofed wooden hovels, in order to create the ‘correct medieval atmosphere’. Add a couple of overweight, ignorant, debauching clerics and a pox marked whore and you have your genuine medieval ambient. You can’t expect to see anything vaguely related to science or technology in such presentations.

Academic medieval historians and historians of science and technology have been fighting an uphill battle against these popular images for many decades now but their efforts rarely reach the general lay public against the flow of the latest bestselling medieval bodice rippers or TV medieval murder mystery. What is needed, is as many semi-popular books on the various aspects of medieval history as possible. Whereby with semi-popular I mean, written for the general lay reader but with its historical facts correct. One such new volume is John Farrell’s The Clock and the Camshaft: And Other Medieval Inventions We Still Can’t Live Without.[1]

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Farrell’s book is a stimulating excursion through the history of technological developments and innovation in the High Middle Ages that played a significant role in shaping the modern world.  Some of those technologies are genuine medieval discoveries and developments, whilst others are ones that either survived or where reintroduced from antiquity. Some even coming from outside of Europe. In each case Farrell describes in careful detail the origins of the technology in question and if known the process of transition into European medieval culture.

The book opens with agricultural innovations, the deep plough, the horse collar and horse shoes, which made it possible to use horses as draught animals instead of or along side oxen, and new crop rotation systems. Farrell explains why they became necessary and how they increased food production leading indirectly to population growth.

Next up we have that most important of commodities power and the transition from the hand milling of grain to the introduction of first watermills and then windmills into medieval culture. Here Farrell points out that our current knowledge would suggest that the more complex vertical water mill preceded the simpler horizontal water mill putting a lie to the common precept that simple technology always precedes more complex technology. At various points Farrell also addresses the question as to whether technological change drives social and culture change or the latter the former.

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Having introduced the power generators, we now have the technological innovations necessary to adapt the raw power to various industrial tasks, the crank and the camshaft. This is fascinating history and the range of uses to which mills were then adapted using these two ingenious but comparatively simple power take offs was very extensive and enriching for medieval society. One of those, in this case an innovation from outside of Europe, was the paper mill for the production of that no longer to imagine our society without, paper. This would of course in turn lead to that truly society-changing technology, the printed book at the end of the Middle Ages.

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Along side paper perhaps the greatest medieval innovation was the mechanical clock. At first just a thing of wonder in the towers of some of Europe’s most striking clerical buildings the mechanical clock with its ability to regulate the hours of the day in a way that no other time keeper had up till then gradually came to change the basic rhythms of human society.

Talking of spectacular clerical buildings the Middle Ages are of course the age of the great European cathedrals. Roman architecture was block buildings with thick, massive stonewalls, very few windows and domed roofs. The art of building in stone was one of the things that virtually disappeared in the Early Middle Ages in Europe. It came back initially in an extended phase of castle building. Inspired by the return of the stonemason, medieval, European, Christian society began the era of building their massive monuments to their God, the medieval cathedrals. Introducing architectural innovation like the pointed arch, the flying buttress and the rib vaulted roof they build large, open buildings flooded with light that soared up to the heavens in honour of their God. Buildings that are still a source of wonder today.

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In this context it is important to note that Farrell clearly explicates the role played by the Catholic Church in the medieval technological innovations, both the good and the bad. Viewed with hindsight the cathedrals can be definitely booked for the good but the bad? During the period when the watermills were introduced into Europe and they replaced the small hand mills that the people had previously used to produce their flour, local Church authorities gained control of the mills, a community could only afford one mill, and forced the people to bring their grain to the Church’s mill at a price of course. Then even went to the extent of banning the use of hand mills.

People often talk of the Renaissance and mean a period of time from the middle of the fifteenth century to about the beginning of the seventeenth century. However, for historians of science there was a much earlier Renaissance when scholars travelled to the boundaries between Christian Europe and the Islamic Empire in the twelfth and thirteenth centuries in order to reclaim the knowledge that the Muslims had translated, embellished and extended in the eight and ninth centuries from Greek sources. This knowledge enriched medieval science and technology in many areas, a fact that justifies its acquisition here in a book on technology.

Another great medieval invention that still plays a major role in our society, alongside the introduction of paper and the mechanical clock are spectacles and any account of medieval technological invention must include their emergence in the late thirteenth century. Spectacles are something that initially emerged from Christian culture, from the scriptoria of the monasteries but spread fairly rapidly throughout medieval society. The invention of eyeglasses would eventually lead to the invention of the telescope and microscope in the early seventeenth century.

Another abstract change, like the translation movement during that first scientific Renaissance, was the creation of the legal concept of the corporation. This innovation led to the emergence of the medieval universities, corporations of students and/or their teachers. There is a direct line connecting the universities that the Church set up in some of the European town in the High Middle Ages to the modern universities throughout the world. This was a medieval innovation that truly helped to shape our modern world.

Farrell’s final chapter in titled The Inventions of Discovery and deals both with the medieval innovations in shipbuilding and the technology of the scientific instruments, such as astrolabe and magnetic compass that made it possible for Europeans to venture out onto the world’s oceans as the Middle Ages came to a close. For many people Columbus’ voyage to the Americas in 1492 represents the beginning of the modern era but as Farrell reminds us all of the technology that made his voyage possible was medieval.

All of the above is a mere sketch of the topics covered by Farrell in his excellent book, which manages to pack an incredible amount of fascinating information into what is a fairly slim volume. Farrell has a light touch and leads his reader on a voyage of discovery through the captivating world of medieval technology. The book is beautifully illustrated by especially commissioned black and white line drawing by Ryan Birmingham. There are endnotes simply listing the sources of the material in main text and an extensive bibliography of those sources. The book also has, what I hope, is a comprehensive index.[2]

Farrell’s book is a good, readable guide to the world of medieval technology aimed at the lay reader but could also be read with profit by scholars of the histories of science and technology and as an ebook or a paperback is easily affordable for those with a small book buying budget.

So remember, next time you settle down with the latest medieval pot boiler with its cast of filthy peasants, debauched clerics and pox marked whores that the paper that it’s printed on and the reading glasses you are wearing both emerged in Europe in the Middle Ages.

[1] John W. Farrell, The Clock and the Camshaft: And Other Medieval Inventions We Still Can’t Live Without, Prometheus Books, 2020.

[2] Disclosure: I was heavily involved in the production of this book, as a research assistant, although I had nothing to do with either the conception or the actual writing of the book that is all entirely John Farrell’s own work. However, I did compile the index and I truly hope it will prove useful to the readers.

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Filed under Book Reviews, History of science, History of Technology, Mediaeval Science

The emergence of modern astronomy – a complex mosaic: Part XL

The event that would eventually lead to Isaac Newton writing and publishing his magnum opus, the Philosophiæ Naturalis Principia Mathematica (the Mathematical Principles of Natural Philosophy), took place in a London coffee house.

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Title page of ‘Principia’, first edition (1687). Source: Wikimedia Commons

This is not quite as strange as it might at first appear, shortly after their first appearance in England around 1650 coffee houses became the favourite meeting places of the English scientific intelligentsia, the astronomers, mathematicians and natural philosophers. Here, these savants would meet up to exchange ideas, discuss the latest scientific theories and pose challenges to each other. These institutions also earned the appellation Penny Universities, as some of those savants, such as William Whiston, Francis Hauksbee and Abraham de Moivre, bettered their incomes by holding lectures or demonstrating experiments to willing audiences, who paid the price of a cup of coffee, a penny, for their intellectual entertainment. Later, after he had become Europe’s most famous living natural philosopher, Isaac Newton would come to hold court in a coffee shop, surrounded by his acolytes, the original Newtonians, distributing words of wisdom and handing round his unpublished manuscripts for scrutiny. However, all that still lay in the future.

One day in January 1684 Christopher Wren, Robert Hooke and Edmond Halley were discussing the actual astronomical theories over a cup of coffee. Wren, today better known as one of England most famous architects, was a leading mathematician and astronomers, who had served both as Gresham and Savilian professor of astronomy. Newton would name him along with John Wallis and William Oughtred as one of the three leading English mathematicians of the seventeenth century.

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Wren, portrait c.1690 by John Closterman Source: Wikimedia Commons

Hooke was at the time considered to be the country’s leading experimental natural philosopher and Halley enjoyed an excellent reputation as a mathematician and astronomer.

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Portrait by Richard Phillips, before 1722 Source: Wikimedia Commons

The topic of discussion was Kepler’s elliptical, heliocentric astronomy and an inverse, squared law of gravity. All three men had arrived separately and independently at an inverse, squared law of gravity probably derived from Huygens’ formula for centrifugal force. Wren posed the question to the other two, whether they could demonstrate that such a law would lead to Kepler’s elliptical planetary orbits.

Hooke asserted that he already had such a demonstration but he would first reveal it to the others after they had admitted that they couldn’t solve the problem. Wren was sceptical of Hooke’s claim and offered a prize of a book worth forty shillings to the first to produce such a demonstration.  Hooke maintained his claim but didn’t deliver. It is worth noting that Hooke never did deliver such a demonstration. Halley, as already said no mean mathematician, tried and failed to solve the problem.

In August 1684 Halley was visiting Cambridge and went to see Newton in his chambers in Trinity College, who, as we know, he had met in 1682.

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Trinity College Cambridge, David Loggan’s print of 1690 Source: Wikimedia Commons

According the Newton’s account as told to Abraham DeMoivre, Halley asked Newton, “what he thought the Curve would be that would be described by the Planets supposing the force of attraction towards the Sun to be reciprocal to the square of the distance from it. Sir Isaac replied immediately that it would be an Ellipse…” Here was Newton claiming to know the answer to Wren’s question. Halley asked Newton how he knew it and he replied, “I have calculated it…” Newton acted out the charade of looking for the supposed solution but couldn’t find it. However he promised Halley that he would send him the solution.

In November Edward Paget, a fellow of Trinity College, brought Halley a nine page thesis entitled De motu corporum in gyrum (On the Motion of Bodies in an Orbit).

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Page of the De motu corporum in gyrum

When Halley read Newton’s little booklet he was immediately aware that he held something truly epoch making in the history of astronomy and physics in his hand. Newton had delivered up a mathematical proof that an elliptical orbit would be produced by an inverse square force situated at one of the foci of the ellipse, thus combining the inverse square law of gravity with Kepler’s first law. He went on to also derive Kepler’s second and third laws as well as laying down the beginnings of a mathematical theory of dynamics. Halley reported details of this extraordinary work to the Royal Society on 10 December 1684:

Mr Halley gave an account, that he had lately seen Mr. Newton at Cambridge, who had shewed him a curious treatise, De motu: which, upon Mr. Halley’s desire, was he said promised to be sent to the Society to be entered upon their register.

Mr. Halley was desired to put Mr. Newton in mind of his promise for securing his invention to himself till such time as he could be at leisure to publish it. Mr. Paget was desired to join with Mr. Halley.

The interest in and the demand to read Newton’s new production was very high but the author decided to improve and rewrite his first offering, triggering one of the most extraordinary episodes in his life.

Although he was Lucasian Professor and would turn forty-two on 25 December 1684, Newton remained a largely unknown figure in the intellectual world of the late seventeenth century. Following the minor debacle that resulted from the publication of his work in optics in the 1670s he had withdrawn into his shell, living in isolation within the walls of Cambridge University. He carried out his duties as Lucasian Professor but had almost no students to speak of and definitely no disciples. Thanks to the word of mouth propaganda of people like his predecessor as Lucasian Professor, Isaac Barrow, and above all the assiduous mathematics groupie, John Collins, it was rumoured that a mathematical monster slumbered in his chambers in Trinity College but he had done nothing to justify this bruited reputation. His chambers were littered with numerous unfinished scientific manuscripts, mostly mathematical but also natural philosophical and an even larger number of alchemical and theological manuscripts but none of them was in a fit state to publish and Newton showed no indication of putting them into a suitable state. Things now changed, Newton had found his vocation and his muse and the next two and a half years of his life were dedicated to creating the work that would make him into a history of science legend, the reworking of De motu into his Principia.

Over those two and a half years Newton turned his nine-page booklet into a major three-volume work of science. The modern English translation by I B Cohen runs to just over 560 large format pages, although this contains all the additions and alterations made in the second and third editions, so the original would have been somewhat shorter. Halley took over the editorship of the work, copyediting it and seeing it through the press. In 1685 the Royal Society had voted to take over the costs of printing and publishing Newton’s masterpiece, so everything seemed to be going smoothly and then disaster struck twice, firstly in the form of Robert Hooke and secondly in the form of a financial problem.

Hooke never slow to claim his priority in any matter of scientific discovery or invention stated that he alone had first discovered the inverse square law of gravity and that this fact should, indeed must, be acknowledged in full in the preface to Newton’s book. Halley, realising at once the potential danger of the situation, was the first to write to Newton outlining Hooke’s claim to priority, stating it, of course, as diplomatically as possible. Halley’s diplomacy did not work, Newton went ballistic. At first his reaction was comparatively mild, merely pointing out that he had had the inverse square law well before his exchanges with Hook in 1679 and had, in fact, discussed the matter with Wren in 1677, go ask him, Newton said. Then with more time to think about the matter and building up a head of steam, Newton wrote a new letter to Halley tearing into Hooke and his claim like a rabid dog. All of this ended with Newton declaring that he would no longer write volume three of his work. Halley didn’t know this at the time but this was in fact, as we shall see, the most important part of the entire work in which Newton presented his mathematical model of a Keplerian cosmos held together by the law of gravity. Halley remained calm and used all of his diplomatic skills to coax, flatter, persuade and cajole the prickly mathematician into delivering the book as finished. In the end Newton acquiesced and delivered but acknowledgements to Hooke were keep to a minimum and offered at the lowest level of civility.

The financial problem was of a completely different nature. In 1685 the Royal Society had taken over the cost of printing and publishing the deceased Francis Willughby’s Historia piscium as edited by John Ray.

This was an expensive project due to the large number plates that the book contained and the book was, at the time, a flop. This meant when it came time to print and publish Newton’s work the Royal Society was effectively bankrupt. One should note here that the popular ridicule poured out over Willughby’s volume, it having almost prevented Newton’s masterpiece appearing, is not justified. Historia piscium is an important volume in the history of zoology. Halley once again jumped into the breach and took over the costs of printing the volumes; on the 5 July 1687 Halley could write to Newton to inform him that the printing of his Philosophiæ Naturalis Principia Mathematica had been completed.

 

 

 

 

 

 

 

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Filed under Early Scientific Publishing, History of Astronomy, History of Mathematics, History of science, Newton

Mathematics and natural philosophy: Robert G socks it to GG

In my recent demolition of Mario Livio’s very pretentious Galileo and the Science Deniers I very strongly criticised Livio’s repeated claims, based on Galileo’s notorious Il Saggiatore quote on the two books, that Galileo was somehow revolutionary in introducing mathematics into the study of science. I pointed out that by the time Galileo wrote his book this had actually been normal practice for a long time and far from being revolutionary the quote was actually a common place.

Last night whilst reading my current bedtime volume, A Mark Smith’s excellent From Sight to Light: The Passage from Ancient to Modern Optics,(University of Chicago Press, 2015) I came across a wonderfully appropriate quote on the topic from Robert Grosseteste (c.1175–1253). For those that don’t know Grosseteste was an English cleric who taught at Oxford University and who became Bishop of Lincoln. He played an important and highly influential role in medieval science, particularly in helping to establish optics as a central subject in the medieval university curriculum.

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An early 14th-century portrait of Grosseteste Source: Wikimedia Commons

Of course, this is problematic for Livio, who firmly labelled the Catholic Church as anti-science and who doesn’t think there was any medieval science, remember that wonderfully wrong quote:

Galileo introduced the revolutionary departure from the medieval, ludicrous notion that everything worth knowing was already known.

If this were true then medieval science would be an oxymoron but unfortunately for Livio’s historical phantasy there was medieval science and Grosseteste was one of its major figure. If you want to know more about Grosseteste then I recommend the Ordered Universe website set up by the team from Durham University led by Giles Gasper, Hannah Smithson and  Tom McLeish

I already knew of Grosseteste’s attitude towards natural philosophy and mathematics but didn’t have a suitable quote to hand, so didn’t mention it in my review. Now I do have one. Let us first remind ourselves what Galileo actually said in Il Saggiatore:

Philosophy [i.e. natural philosophy] is written in this grand book — I mean the Universe — which stands continually open to our gaze, but it cannot be understood unless one first learns to comprehend the language and interpret the characters in which it is written. It is written in the language of mathematics, and its characters are triangles, circles, and other geometrical figures, without which it is humanly impossible to understand a single word of it; without these, one is wandering around in a dark labyrinth.

And now what Grosseteste wrote four hundred years earlier in his De lineis, angulis et figuris (On lines, angles and figures) between 1220 and 1235:

“…a consideration of lines, angles and fugures is of the greatest utility because it is impossible to gain a knowledge of natural philosophy without them…for all causes of natural effects must be expressed by means of lines, angles and figures”

Remarkably similar is it not!

 

 

 

 

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Filed under History of Mathematics, History of science, Mediaeval Science

Galileo sources: a starter kit

Following my last post, numerous people have asked me for book recommendations on Galileo and his opponents. What follows is a list of books that I have and have consulted to create my Galileo. I should add that over the years I have also read a cartload of academic papers on Galileo and related topics. What I list here is only a small fraction of the available literature on the topic. My friend Pierre, the editor of the Simon Marius book, who is a real Galileo expert, I’m not, has currently 1514 items listed in his Galileo bibliography and even that is only a small fraction.

L. Heilbron, Galileo, OUP, 2010

David Wootton, Galileo: Watcher of the Skies, Yale University Press, 2010

Mario Biagioli, Galileo Courtier: The Practice of Science in The Culture of Absolutism, University of Chicago Press, 1993

Mario Biagioli, Galileo’s Instruments of Credit: Telescopes, Images, Secrecy, University of Chicago Press, 2006

William R. Shea & Mariano Artigas, Galileo in Rome: The Rise and Fall of a Troublesome Genius, OUP, 2003

Maurice A. Finocchiaro, On Trial for Reason: Science, Religion, and Culture in the Galileo Affair, OUP, 2019

 

Galileo Galilei, trans. Albert van Helden, Sidereus Nuncius or The Sidereal Messenger, University of Chicago Press, 1989

Galileo Galilei, trans. Stillman Drake, Dialogue Concerning the Two Chief World Systems, University of California Press, 1967

Galileo Galilei, trans. Henry Crew & Alfonso de Salvio, Dialogues Concerning Two New Science, Dover, 1954

Discoveries and Opinions of Galileo, translated with an Introduction and Notes by Stillman Drake, Anchor Books, 1957. (Starry Messenger, Letter to the Grand Duchess Christina, plus excerpts from Letters on Sunspots & The Assayer)

The Essential Galileo, Edited and Translated by Maurice A. Finocchiaro, Hackett Publishing Company, 2008

Galileo on the World Systems: A New Abridged Translation and Guide, Maurice A. Finocchiaro, University of California Press, 1997

Galileo Galilei & Christoph Scheiner, On Sunspots, Translated and Introduced by Eileen Reeves & Albert van Helden, University of Chicago Press, 2010

Eileen Reeves, Galileo’s Glassworks: The Telescope and the Mirror, Harvard University Press, 2008

Massimo Bucciantini, Michele Canmerota, Franco Giudice, Galileo’s Telescope’s: A European Story, Harvard University Press, 2015

James M Lattis, Between Copernicus and Galileo: Christoph Clavius and the Collapse of Ptolemaic Cosmology, University of Chicago Press, 1994

Franz Daxecker, Der Physiker und Astronom Christoph Scheiner, Universitätsverlag Wagner, 2006 (I don’t know of anything good on Scheiner in English)

Christopher M Graney, Setting Aside All Authority: Giovanni Battista Riccioli and the Science against Copernicanism in the Age of Galileo, University of Notre Dame Press, 2015

Mordechai Feingold, Jesuit Science and the Republic of Letters, MIT Press, 2002

Hans Gaab & Pierre Leich eds., Simon Marius and His Research, Springer, 2018

 

 

 

 

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Filed under Book Reviews, History of Astronomy, History of science

The Electric Showman

The are some figures in #histSTM, who, through some sort of metamorphosis, acquire the status of cult gurus, who were somehow super human and if only they had been properly acknowledged in their own times would have advanced the entire human race by year, decades or even centuries. The most obvious example is Leonardo da Vinci, who apparently invented, discovered, created everything that was worth inventing, discovering, creating, as well as being the greatest artist of all time. Going back a few centuries we have Roger Bacon, who invented everything that Leonardo did but wasn’t in the same class as a painter. Readers of this blog will know that one of my particular bugbears is Ada Lovelace, whose acolytes claim singlehandedly created the computer age. Another nineteenth century figure, who has been granted god like status is the Serbian physicist and inventor, Nikola Tesla (1856–1943).

The apostles of Tesla like to present him in contrast to, indeed in battle with, Thomas Alva Edison (1847–1931). According to their liturgy Tesla was a brilliant, original genius, who invented everything electrical and in so doing created the future, whereas Edison was poseur, who had no original ideas, stole everything he is credited with having invented and exploited the genius of other to create his reputation and his fortune. You don’t have to be very perceptive to realise that these are weak caricatures that almost certainly bear little relation to the truth. That this is indeed the case is shown by a new, levelheaded biography of Tesla by Iwan Rhys Morus, Tesla and the Electric Future.[1]

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If anyone is up to the job of presenting a historically accurate, balanced biography of Tesla, then it is Morus, who is professor of history at Aberystwyth University and who has established himself as an expert for the history of electricity in the nineteenth century with a series of excellent monographs on the topic, and yes he delivers.

Anybody who picks up Morus’ compact biography looking for a blow by blow description of the epic war between Tesla and Edison is going to be very disappointed, because as Morus points out it basically never really took place; it is a myth. What we get instead is a superb piece of contextual history. Morus presents a widespread but deep survey of the status of electricity in the second half of the nineteenth century and the beginnings of the twentieth century into which he embeds the life story of Tesla.

We have the technological and scientific histories of electricity but also the socio-political history of the role that electricity during the century and above all the futurology. Electricity was seen as the key to the future in all areas of life in the approaching twentieth century. Electricity was hyped as the energy source of the future, as the key to local and long distant communication, and as a medical solution to both physical and psychological illness. In fact it appears that electricity was being touted as some sort of universal panacea for all of societies problems and ills. It was truly the hype of the century. Electricity featured big in the widely popular world exhibitions beginning with the Great Exhibition at Crystal Palace in 1851.

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In these world fairs electricity literally outshone all of the other marvels and wonders on display.

The men, who led the promotion of this new technology, became stars, prophets of an electrical future, most notably Thomas Alva Edison, who became known as the Wizard of Menlo Park.

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Far from the popular image of Edison being Tesla’s sworn enemy, he was the man, who brought Tesla to America and in doing so effectively launched Tesla’s career. Edison also served as a role model for Tesla; from Edison, Tesla learnt how to promote and sell himself as a master of the electric future.

Morus takes us skilfully through the battle of the systems, AC vs. DC in which Tesla, as opposed to popular myth, played very little active part having left Westinghouse well before the active phase. His technology, patented and licenced to Westinghouse, did, however, play a leading role in Westinghouse’s eventually victory in this skirmish over Edison, establishing Tesla as one of the giants in the electricity chess game. Tesla proceeded to establish his reputation as a man of the future through a series of public lectures and interviews, with the media boosting his efforts.

From here on in Tesla expounded ever more extraordinary, visionary schemes for the electric future but systematically failed to deliver.

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His decline was long drawn out and gradual rather than spectacular and the myths began to replace the reality. The electric future forecast throughout the second half of the nineteenth century was slowly realised in the first half of the twentieth but Tesla played almost no role in its realisation.

Morus is himself a master of nineteenth century electricity and its history, as well as a first class storyteller, and in this volume he presents a clear and concise history of the socio-political, public and commercial story of electricity as it came to dominate the world, woven around a sympathetic but realistic biography of Nikola Tesla. His book is excellently researched and beautifully written, making it a real pleasure to read.  It has an extensive bibliography of both primary and secondary sources. The endnotes are almost exclusively references to the bibliography and the whole is rounded off with an excellent index. The book is well illustrated with a good selection of, in the meantime ubiquitous for #histSTM books, grey in grey prints.

Morus’ book has a prominent subtext concerning how we view our scientific and technological future and it fact this is probably the main message, as he makes clear in his final paragraph:

It is a measure of just what a good storyteller about future worlds Tesla was that we still find the story so compelling. It is also the way we still tend to tell stories about imagined futures now. We still tend to frame the way we think about scientific and technological innovation – the things on which our futures will depend – in terms of the interventions of heroic individuals battling against the odds. A hundred years after Tesla, it might be time to start thinking about other ways of talking about the shape of things to come and who is responsible who is responsible for shaping them.

If you want to learn about the history of electricity in the nineteenth century, the life of Nikola Tesla or how society projects its technological futures then I really can’t recommend Iwan Rhys Morus excellent little volume enough. Whether hardback or paperback it’s really good value for money and affordable for even the smallest of book budgets.

[1] Iwan Rhys Morus, Tesla and the Electric Future, Icon books, London, 2019

 

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Filed under Book Reviews, History of Physics, History of science, History of Technology

The emergence of modern astronomy – a complex mosaic: Part XXXIV

Without any doubt the biggest impact on the discussion of astronomy and cosmology at the beginning of the seventeenth century was made by the invention of the telescope in 1608 and the subsequent discoveries that were made by astronomers with the new revolutionary instrument. That the Moon was not smooth and perfect as claimed by Aristotle but had geological features like the Earth, that the Milky Way and some nebula resolved into separate stars when viewed through the telescope, that the Sun had spots, that Jupiter had four Moons orbiting it and lastly that Venus displayed phases showing that it must orbit the Sun and not the Earth. All of these, for the times, amazing discoveries were made between the end of 1609 and 1613 then the stream of new discoveries dried up as suddenly as it had begun, why? The problem was a technological one.

All of these initial discoveries had been made using so-called Dutch or Galilean telescopes that consisted of a simple tube with two lenses a convex objective at the front and a concave eyepiece at the back.

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Optical diagram of Galilean telescope y – Distant object ; y′ – Real image from objective ; y″ – Magnified virtual image from eyepiece ; D – Entrance pupil diameter ; d – Virtual exit pupil diameter ; L1 – Objective lens ; L2 – Eyepiece lens e – Virtual exit pupil – Telescope equals Source: Wikimedia Commons

A simple instrument with a serious drawback, by adjusting the focal lengths of the lenses one can increase the magnifying power of the instrument but the greater the magnifying power the smaller the field of vision. Most of the discoveries were made using telescopes with a magnifying power of between twenty and thirty. With such telescopes, for example, Galileo could only view about one quarter of the Moon at a time. With magnifying powers above thirty the Dutch telescope becomes effectively useless as an astronomical instrument. The discoveries that had been made by 1613 marked the limit of discoveries that could be made with the simple Dutch telescope, another instrument had to be found if new discoveries were to be made.

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Galileo’s sketches of the Moon from Sidereus Nuncius. Source: Wikimedia Commons

The solution to the problem had already been presented by Johannes Kepler in his Dioptrice published in 1611.

In this important contribution to the science of optics Kepler not only explained, for the first time, how the Dutch telescope functioned but also what became known as the Keplerian or astronomical telescope with a convex objective and a convex eyepiece. He also described the function of the so-called terrestrial telescope with three convex lenses. The astronomical telescope had a much bigger field of view than the Dutch telescope and could thus be constructed with a much higher magnification.

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Source: Wikimedia Commons

It, however, suffered from the problem that whereas the image in the Dutch telescope was upright, in the astronomical telescope it was inverted. Thus the terrestrial telescope the third lens functioning as an inverter, righting the image.

Christoph Scheiner constructed astronomical telescopes for his work observing the Sun.

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Scheiner’s astronomical telescope for recording sunspots Source: Wikimedia Commons

However, Scheiner remained an exception, if a prominent one, and in general it took three decades before other astronomers turned from the Dutch telescope to telescopes with convex lenses. This of course raises the question, why? The inverted image in the simple two lens astronomical telescope was one problem, however not for Scheiner, who projected the Sun’s image onto a sheet of paper and could thus simply invert his drawn image when finished. There is, however another reason for the very protracted move away from the Dutch telescope to the astronomical telescope and that reason bears the name Galileo Galilei.

Since the publication of his Sidereus Nuncius in 1610, Galileo had become the authority for all things connected with telescopic astronomy.

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Title page of Sidereus nuncius, 1610, by Galileo Galilei (1564-1642). *IC6.G1333.610s, Houghton Library, Harvard University Source: Wikimedia Commons

Galileo was also arrogant enough to reject anything that he didn’t discover or originate. He made rude noises about the astronomical telescope praising the advantages of the Dutch telescope against the astronomical telescope, even though they didn’t exist. He was also very rude about and dismissive of Kepler’s Dioptrice claiming that it was unreadable. His authority was sufficient to hinder the adoption of the astronomical telescope.

One of the first to go against the authority of Galileo and construct and observe with an astronomical telescope was the Italian astronomer Francesco Fontana (c. 1558–1656), who as we saw earlier made the telescope with which Zupi first observed the phases of Mercury.

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Fontana drew a new more accurate map of the Moon, discovered the bands visible on Jupiter. He made the first drawings of Mars and discovered its rotation also inferring the rotation of both Jupiter and Saturn. He published a book of all of his discoveries Novae coelestium terrestriumque rerum observationes, et fortasse hactenus non vulgatae  in 1646.

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Italian astronomer Francesco Fontana created woodcuts showing the Moon and the planets as he saw them through a self-constructed telescope. In 1646, he published most of them in the book Novae Coelestium, Terrestriumque Rerum Observationes, et Fortasse Hactenus Non Vulgatae. Source

This turned out to be a major problem as the book also contained discoveries that Fontana claimed to have made, for example new moons of Jupiter Saturn and Venues, which simply didn’t exist. The charitable explanation is that these were optical artefacts produced by his telescope. This highlights another major problem of early telescopic astronomy, the quality of the early telescopes ranged from bad to abysmal.

The quality of the glass used to make the lenses was usually fairly poor. Often discoloured and equally often containing inclusions, bubbles created during the cooling of the glass, which interfered with the optical quality of the glass. All the early lenses were spherical, i.e. their curvature was segment of the surface of a sphere. This was the only shape that could be ground and polished with the technology available at the time. Even so, the further one got from the centre of a lens the more it tended to deviate from the correct form. This meant that the image formed by such lenses tended to be fairly severely distorted. The current theory is that the invention of the telescope occurred not when somebody succeeded in grinding and polishing lenses, spectacle makers had been doing that for three hundred years before the telescope emerged, or when somebody came up with the right combination of lenses, there is evidence that the magnifying property of the combination of a convex and a concave lens was known sometime before the breakthrough, but when somebody (Hans Lipperhey?) first came up with the idea of masking the outer edges of the objective lens reducing the available area to the truly spherical centre and thus creating a sharp image at the cost of a loss of light. Another problem was so-called spherical aberration. A spherical lens doesn’t actually focus light to a single point but the image is spread out over a small area causing it to blur. This was already known to Ibn al-Haytham (c. 965–c. 1040), who also knew the solution, lenses shaped according to the surfaces of ellipsoids or hyperboloids but lens makers in the seventeenth century were incapable of grinding such shapes. A much bigger problem was chromatic aberration. This is caused by the fact that simple lenses focus different wavelengths and thus different colours of light at slightly different points, causing coloured fringes on the images.  However, the discovery of chromatic aberration by Isaac Newton still lay in the future and its solution even further in the future. Over time the telescope makers discovered that making objective lenses with very long focal lengths reduced the problem of spherical and chromatic aberration and so throughout the seventeenth century the telescopes got longer and longer. Given all of these optical problems it is not surprising that astronomers made discoveries that were illusions; it is to a certain extent a wonder that they discovered anything at all.

The major breakthrough in the use of the astronomical telescope came with the invention of the multiple lens eyepiece by Anton Maria Schyrleus de Rheita, born Johann Burkhard Schyri  (1604–1660), an Capuchin monk, who had studied optics and astronomy at the University of Ingolstadt, the university of Christoph Scheiner and Johann Baptist Cysat, which, although they were no longer present when he studied there, still maintained a high standard in these disciplines. Schyri built his own telescopes and made astronomical observations. In 1643 he published his observations in his Novem stellae, which was full of new discoveries but like those of Fontana they mostly weren’t. Much more important was the publication in 1645 of his Oculus Enoch et Eliae in which he describe, without illustrations, a terrestrial telescope with a three lens eyepiece, as well a description of a pair of binoculars.

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Beginning in 1643 he had already begun to manufacture his new telescope together with the Augsburger instrument maker and optician Johann Wiesel (1583–1662), Germany’s first commercial telescope maker.

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Johann Wiesel with one of his telescopes. Copper engraving by Bartholomäus Kilian, 1660 Source: Wikimedia Commons

The Wiesel/ Schyri terrestrial telescope, which had an upright image, a wide field of vision and high-level magnification, was a huge success throughout Europe. Not only did they sell well but they were soon copied and used not just on land but also as astronomical instruments. In his book Schyri also coined the terms ocular and objective for telescopes.

The Wiesel/ Schyri telescope broke the dam and opened the market for convex lens, astronomical telescopes. In Italy Eustachio Divini (1610–1685) a clockmaker began to manufacture optical instruments becoming by 1646 the leading optician in Italy selling astronomical telescopes throughout Europe.

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Portrait of Eustachio Divini in Carlo Antonio Manzini’s “Dioptrica Pratica” Bologna 1660 Source: Wikimedia Commons

In 1649 he published his first book of observations centred round a spectacular selenography.

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Eustachio Divini Selenography

He would later go on to make detailed observations of Jupiter, the changing shape of the belts, the big red spot and the shadows cast by the satellites. His observation confirmed the axial rotation of the planet.

Divini’s reputation as Europe’s leading telescope maker/astronomer was usurped in 1656 by the still young Dutch polymath Christiaan Huygens (1629–1695), who designed his own astronomical telescope, which he constructed with his brother Constantijn (1628–1697) and with which he discovered Titan the largest of Saturn’s moons.

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Christiaan Huygens by Caspar Netscher, 1671, Museum Boerhaave, Leiden Source: Wikimedia Commons

The year before he had already staked his territory by explaining that the strange observations made by various astronomers of Saturn were in fact differing views of rings surrounding the planet. He explained this in his Systema Saturnium in 1659, which also contained the first telescopic sketches of the Orion Nebula. His explanation of the rings led to a major dispute with Divini, who was convinced that they were a belt of satellites.

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Huygens’ explanation for the aspects of Saturn, Systema Saturnium, 1659 Source: Wikimedia Commons

In the same year he made the first observations of a surface feature of another planet, Syrtis Major, a volcanic plain on Mars, using it to determine the length of the Martian day.

Divini lost his status as Italy’s prime telescope maker to the Campani brothers Matteo (1620–after 1678) and Giuseppe (1635–1715) in a series of contests staged the Accademia del Cimento to test the quality of their telescopes in 1664, which the Campani brothers won, although largely through skulduggery. Of interest is that the quality of the telescopes were compared by reading printed letters though them, a forerunner of the letter charts in the practice of every ophthalmic optician.

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Giuseppe Campani (1635-1715) Telescope with four tubes, Rome, 1666 Florence, Istituto e Museo di Storia della Scienza, inv. 2556

Although Giuseppe Campani was an active astronomer, who made his own observations and discoveries it is their most famous customer, who made the biggest impact, Giovanni Domenico Cassini (1625–1712), who became Jean-Dominique when he moved to France in 1669.

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Giovanni Cassini artist unknown Source: Wikimedia Commons

Employed as an astronomer at the observatory in Panzano by the Marquis Cornelio Malvasia (1603–1664) from 1648, Cassini was able to study under Giovanni Battista Riccioli (1598–1671) and Francesco Maria Grimaldi (1618–1663), themselves important telescopic astronomers, who produced an important lunar map, at the University of Bologna.

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Riccioli/Grimaldi Lunar Map Source: Wikimedia Commons

In 1650 he was appointed professor for astronomy at the university. During his time in Bologna Cassini was able, with the assistance of Riccioli and Grimaldi, using a meridian line in the San Petronio Basilica to prove that that either the Sun’s orbit around the Earth or the Earth’s orbit around the Sun was an ellipse thus confirming a part of Kepler’s astronomical system. The experiment was unable to determine if the system was geo-heliocentric or heliocentric.

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San Petronio Basilica The winter solstice end of the meridian line Source: Wikimedia Commons

As Europe’s leading telescopic astronomer Cassini discovered and published surface markings on Mars, determined the rotation periods of Mars and Jupiter, discovered four satellites of Saturn–Iapetus and Rhea in 1671 and 1672 followed by Tethys and Dione in 1684–he is also credited with the co-discovery with Robert Hooke of the big red spot on Jupiter. He was able to determine the orbits of the moons of Jupiter with enough accuracy that they could be used as a clock to determine longitude, as originally suggested by Galileo. A spin off of this research was the determination of the speed of light by Cassini’s assistant, Ole Rømer (1644–1710). He also showed that both the moons of Jupiter and Saturn obeyed Kepler’s third law, a fact used later by Newton in his Principia Mathematica.

The problem of aberration and the semi-solution of having objectives with ever-longer focal lengths led to the development of the aerial telescope. These are extremely long focal length telescopes that have an objective lens and an eyepiece but no tube, instead having some mechanism to keep the two lens units aligned. Christiaan Huygens constructed one with a cord between the objective and the ocular.

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An engraving of Huygens’s 210-foot aerial telescope showing the eyepiece and objective mounts and connecting string. Source: Wikimedia Commons

The most famous aerial telescope, however, was that of Johannes Hevelius (1611–1687), a wealthy beer brewer and amateur astronomer who lived in Danzig.

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Johannes Hevelius and his wife Elizabeth observing together Source: Wikimedia Commons

Hevelius constructed a telescope with a focal length of 150 feet, which became a tourist attraction.

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1673 engraved illustration of Johannes Hevelius’s 8 inch telescope with an open work wood and wire “tube” that had a focal length of 150 feet to limit chromatic aberration. Source: Wikimedia Commons

He also built a fully equipped observatory on the roof of his brewery and undertook extensive astronomical observations. He, like other, produced a very detailed map of the Moon, discovered four comets and hypothesised that comets obit the Sun on parabolic orbits, created an extensive star atlas in which he described and named ten new constellations, seven of which are still included in official star maps.

With the exception of the discovery of the five largest moons of Saturn, this second wave of seventeenth century telescopic astronomy, starting in about 1640 and continuing till the end of the century, was not as spectacular as the first one. However by the end of the century the small discoveries had accumulated to create a completely different picture of the heavens to the one that existed at the beginning. Planets were no longer Aristotle’s perfectly smooth, spherical bodies but had satellites and surface features, rotated on their axes and had determinable day lengths. The Moon had been accurately mapped by several independent astronomers and there was absolutely no doubt in the minds of the observers that it was fundamentally earth like. The position of many more stars had been accurately mapped and the orbits of the newly discovered satellites had been accurately determined. The celestial spheres of Aristotle and Ptolemaeus had been totally banished. During this second wave of telescopic observation and discovery telescopic astronomy came of age and became a recognised scientific discipline.

In 1669 Cassini was appointed the first director of the Paris Observatory, which had been founded in 1667 by the French minister of finance, Jean-Baptiste Colbert (1619–1683).

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An engraving of The Paris Observatory in the beginning of the 18th century with the wooden “Marly Tower” on the right, erected by Cassini to support both tubed and aerial very long telescopes Source: Wikimedia Commons

The founding of the Paris observatory was followed in 1675 with the founding in England of the Royal Observatory in Greenwich by Charles II, with John Flamsteed appointed in the same year as the first Astronomer Royal.

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Royal Observatory Greenwich Source: Wikimedia Commons

Berlin came somewhat later in 1700 with the appointment of Gottfried Kirch (1639–1710) but who never lived to see his observatory, which first opened in 1711. What we see here is a radical change in the status of astronomy. Whereas for most of the seventeenth century astronomy had been the province of either private citizens or university professors it now became the province of governments with astronomers appointed as civil servants required to deliver astronomical data for cartographical and navigational purposes.

 

 

 

 

 

 

 

 

 

 

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How Renaissance Nürnberg became the Scientific Instrument Capital of Europe

This is a writen version of the lecture that I was due to hold at the Science and the City conference in London on 7 April 2020. The conference has for obvious reasons been cancelled and will now take place on the Internet. You can view the revised conference program here.

The title of my piece is, of course, somewhat hyperbolic, as far as I know nobody has ever done a statistical analysis of the manufacture of and trade in scientific instruments in the sixteenth century. However, it is certain that in the period 1450-1550 Nürnberg was one of the leading European centres both for the manufacture of and the trade in scientific instruments. Instruments made in Nürnberg in this period can be found in every major collection of historical instruments, ranging from luxury items, usually made for rich patrons, like the column sundial by Christian Heyden (1526–1576) from Hessen-Kassel

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Column Sundial by Christian Heyden Source: Museumslandschaft Hessen-Kassel

to cheap everyday instruments like this rare (rare because they seldom survive) paper astrolabe by Georg Hartman (1489–1564) from the MHS in Oxford.

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Paper and Wood Astrolabe Hartmann Source: MHS Oxford

I shall be looking at the reasons why and how Nürnberg became such a major centre for scientific instruments around 1500, which surprisingly have very little to do with science and a lot to do with geography, politics and economics.

Like many medieval settlements Nürnberg began simply as a fortification of a prominent rock outcrop overlooking an important crossroads. The first historical mention of that fortification is 1050 CE and there is circumstantial evidence that it was not more than twenty or thirty years old. It seems to have been built in order to set something against the growing power of the Prince Bishopric of Bamberg to the north. As is normal a settlement developed on the downhill slopes from the fortification of people supplying services to it.

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A fairly accurate depiction of Nürnberg from the Nuremberg Chronicle from 1493. The castles (by then 3) at the top with the city spreading down the hill. Large parts of the inner city still look like this today

Initially the inhabitants were under the authority of the owner of the fortification a Burggraf or castellan. With time as the settlement grew the inhabitants began to struggle for independence to govern themselves.

In 1200 the inhabitants received a town charter and in 1219 Friedrich II granted the town of Nürnberg a charter as a Free Imperial City. This meant that Nürnberg was an independent city-state, which only owed allegiance to the king or emperor. The charter also stated that because Nürnberg did not possess a navigable river or any natural resources it was granted special tax privileges and customs unions with a number of southern German town and cities. Nürnberg became a trading city. This is where the geography comes into play, remember that important crossroads. If we look at the map below, Nürnberg is the comparatively small red patch in the middle of the Holy Roman Empire at the beginning of the sixteenth century. If your draw a line from Paris to Prague, both big important medieval cities, and a second line from the border with Denmark in Northern Germany down to Venice, Nürnberg sits where the lines cross almost literally in the centre of Europe. Nürnberg also sits in the middle of what was known in the Middle Ages as the Golden Road, the road that connected Prague and Frankfurt, two important imperial cities.

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You can also very clearly see Nürnberg’s central position in Europe on Erhard Etzlaub’s  (c. 1460–c. 1531) pilgrimage map of Europe created for the Holy Year of 1500. Nürnberg, Etzlaub’s hometown, is the yellow patch in the middle. Careful, south is at the top.

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Over the following decades and centuries the merchant traders of Nürnberg systematically expanded their activities forming more and more customs unions, with the support of various German Emperors, with towns, cities and regions throughout the whole of Europe north of Italy. Nürnberg which traded extensively with the North Italian cities, bringing spices, silk and other eastern wares, up from the Italian trading cities to distribute throughout Europe, had an agreement not to trade with the Mediterranean states in exchange for the Italians not trading north of their northern border.

As Nürnberg grew and became more prosperous, so its political status and position within the German Empire changed and developed. In the beginning, in 1219, the Emperor appointed a civil servant (Schultheis), who was the legal authority in the city and its judge, especially in capital cases. The earliest mention of a town council is 1256 but it can be assumed it started forming earlier. In 1356 the Emperor, Karl IV, issued the Golden Bull at the Imperial Diet in Nürnberg. This was effectively a constitution for the Holy Roman Empire that regulated how the Emperor was to be elected and, who was to be appointed as the Seven Prince-electors, three archbishops and four secular rulers. It also stipulated that the first Imperial Diet of a newly elected Emperor was to be held in Nürnberg. This stipulation reflects Nürnberg’s status in the middle of the fourteenth century.

The event is celebrated by the mechanical clock ordered by the town council to be constructed for the Frauenkirche, on the market place in 1506 on the 150th anniversary of the Golden Bull, which at twelve noon displays the seven Prince-electors circling the Emperor.

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Mechanical clock on the Frauenkirche overlooking the market place in Nürnberg. Ordered by the city council in 1506 to celebrate the 150th anniversary of the issuing of the Golden Bull at the Imperial Diet in 1356

Over time the city council had taken more and more power from the Schultheis and in 1385 they formally bought the office, integrating it into the councils authority, for 8,000 gulden, a small fortune. In 1424 Emperor, Sigismund appointed Nürnberg the permanent residence of the Reichskleinodien (the Imperial Regalia–crown, orb, sceptre, etc.).

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The Imperial Regalia

This raised Nürnberg in the Imperial hierarchy on a level with Frankfurt, where the Emperor was elected, and Aachen, where he was crowned. In 1427, the Hohenzollern family, current holders of the Burggraf title, sold the castle, which was actually a ruin at that time having been burnt to the ground by the Bavarian army, to the town council for 120,000 gulden, a very large fortune. From this point onwards Nürnberg, in the style of Venice, called itself a republic up to 1806 when it was integrated into Bavaria.

In 1500 Nürnberg was the second biggest city in Germany, after Köln, with a population of approximately 40,000, about half of which lived inside the impressive city walls and the other half in the territory surrounding the city, which belonged to it.

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Map of the city-state of Nürnberg by Abraham Ortelius 1590. the city itself is to the left just under the middle of the map. Large parts of the forest still exists and I live on the northern edge of it, Dormitz is a neighbouring village to the one where I live.

Small in comparison to the major Italian cities of the period but even today Germany is much more decentralised with its population more evenly distributed than other European countries. It was also one of the richest cities in the whole of Europe.

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Nürnberg, Plan by Paul Pfinzing, 1594 Castles in the top left hand corner

Nürnberg’s wealth was based on two factors, trading, in 1500 at least 27 major trade routes ran through Nürnberg, which had over 90 customs unions with cities and regions throughout Europe, and secondly the manufacture of trading goods. It is now time to turn to this second branch of Nürnberg’s wealth but before doing so it is important to note that whereas in other trading centres in Europe individual traders competed with each other, Nürnberg function like a single giant corporation, with the city council as the board of directors, the merchant traders cooperating with each other on all levels for the general good of the city.

In 1363 Nürnberg had more than 1200 trades and crafts masters working in the city. About 14% worked in the food industry, bakers, butchers, etc. About 16% in the textile industry and another 27% working leather. Those working in wood or the building branch make up another 14% but the largest segment with 353 masters consisted of those working in metal, including 16 gold and silver smiths. By 1500 it is estimated that Nürnberg had between 2,000 and 3,000 trades and crafts master that is between 10 and 15 per cent of those living in the city with the metal workers still the biggest segment. The metal workers of Nürnberg produced literally anything that could be made of metal from sewing needles and nails to suits of armour. Nürnberg’s reputation as a producer rested on the quality of its metal wares, which they sold all over Europe and beyond. According to the Venetian accounts books, Nürnberg metal wares were the leading export goods to the orient. To give an idea of the scale of production at the beginning of the 16th century the knife makers and the sword blade makers (two separate crafts) had a potential production capacity of 80,000 blades a week. The Nürnberger armourers filled an order for armour for 5,000 soldiers for the Holy Roman Emperor, Karl V (1500–1558).

The Nürnberger craftsmen did not only produce goods made of metal but the merchant traders, full blood capitalists, bought into and bought up the metal ore mining industry–iron, copper, zinc, gold and silver–of Middle Europe, and beyond, (in the 16th century they even owned copper mines in Cuba) both to trade in ore and to smelt ore and trade in metal as well as to ensure adequate supplies for the home production. The council invested heavily in the industry, for example, providing funds for the research and development of the world’s first mechanical wire-pulling mill, which entered production in 1368.

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The wirepulling mills of Nürnberg by Albrecht Dürer

Wire was required in large quantities to make chainmail amongst other things. Around 1500 Nürnberg had monopolies in the production of copper ore, and in the trade with steel and iron.  Scientific instruments are also largely made of metal so the Nürnberger gold, silver and copper smiths, and toolmakers also began to manufacture them for the export trade. There was large scale production of compasses, sundials (in particular portable sundials), astronomical quadrants, horary quadrants, torquetum, and astrolabes as well as metal drawing and measuring instruments such as dividers, compasses etc.

The city corporation of Nürnberg had a couple of peculiarities in terms of its governance and the city council that exercised that governance. Firstly the city council was made up exclusively of members of the so-called Patrizier. These were 43 families, who were regarded as founding families of the city all of them were merchant traders. There was a larger body that elected the council but they only gave the nod to a list of the members of the council that was presented to them. Secondly Nürnberg had no trades and crafts guilds, the trades and crafts were controlled by the city council. There was a tight control on what could be produced and an equally tight quality control on everything produced to ensure the high quality of goods that were traded. What would have motivated the council to enter the scientific instrument market, was there a demand here to be filled?

It is difficult to establish why the Nürnberg city corporation entered the scientific instrument market before 1400 but by the middle of the 15th century they were established in that market. In 1444 the Catholic philosopher, theologian and astronomer Nicolaus Cusanus (1401–1464) bought a copper celestial globe, a torquetum and an astrolabe at the Imperial Diet in Nürnberg. These instruments are still preserved in the Cusanus museum in his birthplace, Kues on the Mosel.

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The Cusanus Museum in Kue

In fact the demand for scientific instrument rose sharply in the 15th & 16th centuries for the following reasons. In 1406 Jacopo d’Angelo produced the first Latin translation of Ptolemy’s Geographia in Florence, reintroducing mathematical cartography into Renaissance Europe. One can trace the spread of the ‘new’ cartography from Florence up through Austria and into Southern Germany during the 15th century. In the early 16th century Nürnberg was a major centre for cartography and the production of both terrestrial and celestial globes. One historian of cartography refers to a Viennese-Nürnberger school of mathematical cartography in this period. The availability of the Geographia was also one trigger of a 15th century renaissance in astronomy one sign of which was the so-called 1st Viennese School of Mathematics, Georg von Peuerbach (1423–1461) and Regiomontanus (1436–176), in the middle of the century. Regiomontanus moved to Nürnberg in 1471, following a decade wandering around Europe, to carry out his reform of astronomy, according to his own account, because Nürnberg made the best astronomical instruments and had the best communications network. The latter a product of the city’s trading activities. When in Nürnberg, Regiomontanus set up the world’s first scientific publishing house, the production of which was curtailed by his early death.

Another source for the rise in demand for instruments was the rise in interest in astrology. Dedicated chairs for mathematics, which were actually chairs for astrology, were established in the humanist universities of Northern Italy and Krakow in Poland early in the 15th century and then around 1470 in Ingolstadt. There were close connections between Nürnberg and the Universities of Ingolstadt and Vienna. A number of important early 16th century astrologers lived and worked in Nürnberg.

The second half of the 15th century saw the start of the so-called age of exploration with ships venturing out of the Iberian peninsular into the Atlantic and down the coast of Africa, a process that peaked with Columbus’ first voyage to America in 1492 and Vasco da Gama’s first voyage to India (1497–199). Martin Behaim(1459–1507), son of a Nürnberger cloth trading family and creator of the oldest surviving terrestrial globe, sat on the Portuguese board of navigation, probably, according to David Waters, to attract traders from Nürnberg to invest in the Portuguese voyages of exploration.  This massively increased the demand for navigational instruments.

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The Erdapfel–the Behaim terrestial globe Germanische National Museum

Changes in the conduct of wars and in the ownership of land led to a demand for better, more accurate maps and the more accurate determination of boundaries. Both requiring surveying and the instruments needed for surveying. In 1524 Peter Apian (1495–1552) a product of the 2nd Viennese school of mathematics published his Cosmographia in Ingolstadt, a textbook for astronomy, astrology, cartography and surveying.

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The Cosmographia went through more than 30 expanded, updated editions, but all of which, apart from the first, were edited and published by Gemma Frisius (1508–1555) in Louvain. In 1533 in the third edition Gemma Frisius added an appendix Libellus de locorum describendum ratione, the first complete description of triangulation, the central method of cartography and surveying down to the present, which, of course in dependent on scientific instruments.

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In 1533 Apian’s Instrumentum Primi Mobilis 

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was published in Nürnberg by Johannes Petreius (c. 1497–1550) the leading scientific publisher in Europe, who would go on ten years later to publish, Copernicus’ De revolutionibus, which was a high point in the astronomical revival.

All of this constitutes a clear indication of the steep rise in the demand for scientific instruments in the hundred years between 1450 and 1550; a demand that the metal workers of Nürnberg were more than happy to fill. In the period between Regiomontanus and the middle of the 16th century Nürnberg also became a home for some of the leading mathematici of the period, mathematicians, astronomers, astrologers, cartographers, instrument makers and globe makers almost certainly, like Regiomontanus, at least partially attracted to the city by the quality and availability of the scientific instruments.  Some of them are well known to historians of Renaissance science, Erhard Etzlaub, Johannes Werner, Johannes Stabius (not a resident but a frequent visitor), Georg Hartmann, Johannes Neudörffer and Johannes Schöner.**

There is no doubt that around 1500, Nürnberg was one of the major producers and exporters of scientific instruments and I hope that I have shown above, in what is little more than a sketch of a fairly complex process, that this owed very little to science but much to the general geo-political and economic developments of the first 500 years of the city’s existence.

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One of the most beautiful sets on instruments manufactured in Nürnberg late 16th century. Designed by Johannes Pretorius (1537–1616), professor for astronomy at the Nürnberger University of Altdorf and manufactured by the goldsmith Hans Epischofer (c. 1530–1585) Germanische National Museum

 

**for an extensive list of those working in astronomy, mathematics, instrument making in Nürnberg (542 entries) see the history section of the Astronomie in Nürnberg website, created by Dr Hans Gaab.

 

 

 

 

 

 

 

 

 

 

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The emergence of modern astronomy – a complex mosaic: Part XXXII

In the seventeenth century large parts of Europe were still Catholic; in 1616 the Catholic Church had placed De revolutionibus and all other texts promoting a heliocentric world-view on the Index of Forbidden Books and in 1632 they added Galileo’s Dialogo sopra i due massimi sistemi del mondo (Dialogue Concerning the Two Chief World Systems), so the question arises, how was knowledge of the heliocentric model disseminated? The answer is, somewhat surprisingly, that the dissemination of the heliocentric hypothesis was, even in Catholic countries, widespread and through diverse channels.

First off, although De revolutionibus was placed on the Index in 1616, it was only placed there until corrected. In fact, somewhat against the norm, it was actually corrected surprisingly quickly and, with a few rather minor changes, became freely available again for Catholic scholars by 1621. The astronomers within the Church had been able to convince the theologians of the importance of Copernicus’ work as an astronomy book even if one rejected the truth of the heliocentric hypothesis. The only changes were that any statements of the factual truth of the hypothesis were removed, so anybody with a censured copy could quite happily think those statements back into place for himself.

The Lutheran Protestant Church also rejected the heliocentric hypothesis but never formally banned it in anyway. In fact, from very early on, the astronomers and mathematicians at the Lutheran universities had begun teaching Copernicus’ work as a purely mathematical, instrumentalist thesis, whilst rejecting it as a true account of the cosmos. It was used, for example, by Erasmus Reinhold (1511–1553) using Copernicus’ data and mathematical models to calculate the Prutenicae Tabulae (1551), without however committing to heliocentricity. They maintained this instrumentalist approach throughout the seventeenth century utilising the most up to date books as they became available, without crediting the hypothesis with any truth. From about 1630 onwards, Kepler’s Epitome Astronomiae Copernicanae (3 Vols. 1617–1621) and his Tabulae Rudolphinae (1627) became the leading textbooks for teaching the heliocentric hypothesis. The latter was used both sides of the religious divide because it was quite simply vastly superior in its accuracy to any other volume of planetary tables on the market.

However, the mainstream pro heliocentricity texts were not the only published sources spreading the information of the heliocentric hypothesis and making the information available across Europe. One, perhaps surprising, source was the yearly astrological almanacs.

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These annual pamphlets or booklets contained the astronomical and astrological data for the coming year, phases of the moon, hours of sunlight, any eclipse or planetary conjunctions etc. They also included basic horoscopes for the year covering political developments, weather forecasts, health issues and whatever. These were immensely popular and printed on cheap paper and not bound were reasonably cheap, so they sold in comparatively vast numbers, having much larger editions than any printed books. The market was fiercely contested so to make sure that their product was preferred by the potential customers, who came from all levels of society, the authors and/or publishers included editorials covering a wide range of topic. These editorials often contained medical issues but in the seventeenth century they also often contained popular expositions of the heliocentric hypothesis. Given the widespread consume of these publications it meant that basic knowledge of heliocentricity reached a large audience.

Another important source for the dissemination of the heliocentric hypothesis was in the writings of some of those who, nominally at least, opposed it. I will now take a brief look at two of those authors the Italian, Jesuit astronomer, mathematician and physicist Giovanni Battista Riccioli (1598–1671) and the French, priest, philosopher, astronomer and mathematician Pierre Gassendi (1592–1655) both of whom were highly influential and widely read scholars in the middle of the seventeenth century.

Pierre Gassendi is one of those figures in the history of science, who deserve to be better known than they are. Well known to historians of science and philosophy he remains largely unknown to those outside those disciplines. He was a central figure in the intellectual life of Europe in the middle of the seventeenth century part of the philosophical circle in Paris that included René Descartes, Marin Mersenne, Thomas Hobbes and Jean-Baptiste Morin amongst others. He also travelled to Holland and made the acquaintance of Isaac Beeckman. Probably his most important contribution to the evolution of science was his attempt to reconcile Epicurean atomism with Christian theology.

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Pierre Gassendi after Louis-Édouard Rioult. Source: Wikimedia Commons

Throughout his life he actively promoted the work of both Kepler and Galileo. He wrote and published a biography of Nicolas-Claude Fabri de Peiresc (1580–1637), his patron, an astronomer and another supporter of the works of Galileo.  Shortly before the end of his life he published a collective biography of Tycho Brahe, Nicolaus Copernicus, Georg von Peuerbach and Johannes Regiomontanus: Tychonis Brahei, equitis Dani, astronomorum Coryphaei, vita; accessit Nicolai Copernici; Georgii Peurbachii, et Joannis Regiomontani, astronomorum celebrium vita (1654).

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In 1645 Gassendi was appointed professor of mathematics at the Collège Royal in Paris and during his time there he wrote and published an astronomy textbook presenting both the Tychonic and heliocentric astronomical systems, Institvtio astronomica, iuxta hypothesis tam vetervm, qvam Copernici, et Tychonis. Dictata à Petro Gassendo … Eivsdem oratio inauguralis iteratò edita (1647).

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Although, as a Catholic priest, he presented the Tychonic system as the correct one his treatment of heliocentricity was detailed, thorough and very sympathetic. Perhaps somewhat too sympathetic, as it led to him being investigated by the Inquisition, who however gave him a clean bill of health. Because of his excellent reputation his book was read widely and acted as a major source for the dissemination of the heliocentric hypothesis.

Like Gassendi, Riccioli was an important and influential figure in seventeenth century science. From 1636 he was professor in Bologna where did much important work in astronomy and physics as well as being the teacher of Giovanni Domenico Cassini (1625–1712), who we will meet later in this series.

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Riccioli as portrayed in the 1742 Atlas Coelestis (plate 3) of Johann Gabriel Doppelmayer. Source: Wikimedia Commons

He is perhaps best known for his pioneering selenology together with his former student, Francesco Maria Grimaldi (1618–1663), which provided the nomenclature system for the moons geological features still in use today.  As stated earlier it was Riccioli, who provided the necessary empirical proof of Galileo’s laws of fall. He also hypothesised the existence of, what later became known as the Coriolis effect, if the Earth did in fact rotate.

If a ball is fired along a Meridian toward the pole (rather than toward the East or West), diurnal motion will cause the ball to be carried off [that is, the trajectory of the ball will be deflected], all things being equal: for on parallels of latitude nearer the poles, the ground moves more slowly, whereas on parallels nearer the equator, the ground moves more rapidly.

Having failed to detect it, it does exist but is too small to be measured using the methods available to Riccioli, he concluded that the Earth does not in fact rotate.

This was just one of many arguments pro and contra the heliocentric hypothesis that Riccioli presented in his Almagestum novum astronomiam veterem novamque complectens observationibus aliorum et propriis novisque theorematibus, problematibus ac tabulis promotam (Vol. I–III, 1651), a vast astronomical encyclopaedia that became a standard astronomical textbook throughout Europe. Although Riccioli rejected the heliocentric hypothesis his very detailed and thorough analysis of it with all its strengths and weaknesses meant that his book became a major source for those wishing to learn about it.

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Frontispiece of Riccioli’s 1651 New Almagest. Source: Wikimedia Commons

This famous frontispiece shows a semi-Tychonic system being weighed against a heliocentric system and being found more substantial. Ptolemaeus lies on the ground under the scales obviously defeated but he is saying “I will rise again”.

As we have seen, although not provable at that stage and nominally banned by the Catholic Church, information on and details of the heliocentric hypothesis were widespread and easily accessible throughout the seventeenth century from multiple sources and thus knowledge of it and interest in it continued to spread throughout the century.

 

 

 

 

 

 

 

 

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War, politics, religion and scientia

There is a strong tendency to view the history of science and the people who produced it in a sort of vacuum, outside of everyday society–Copernicus published this, Kepler published that, Newton synthesised it all… In fact the so-called scientific revolution took place in one of the most troubled times in European history, the age of the religious wars, the main one of which the Thirty Years War is thought to have been responsible directly and indirectly for the death of between one third and two thirds of the entire population of middle Europe. Far from being isolated from this turbulence the figures, who created modern science, were right in the middle of it and oft deeply involved and affected by it.

The idea for this blog post sort of crept into my brain as I was writing my review, two weeks ago, of two books about female spies during the English Revolution and Interregnum that is the 1640s to the 1660s. Isaac Newton was born during this period and grew up during it and, as I will now sketch, was personally involved in the political turbulence that followed on from it.

Born on Christmas Day in 1642 (os) shortly after the outbreak of the first of the three wars between the King and Parliament, Britain’s religious wars, he was just nine years old when Charles I was executed at the end of the second war.

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Portrait of Newton by Godfrey Kneller, 1689 Source: Wikimedia Commons

Newton was too young to be personally involved in the wars but others whose work would be important to his own later developments were. The Keplerian astronomer William Gascoigne (1612-1644), who invented the telescope micrometer, an important development in the history of the telescope, died serving in the royalist forces at the battle of Marston Moor. The mathematician John Wallis (1616–1703), whose Arithmetica Infinitorum (1656) strongly influenced Newton’s own work on infinite series and calculus, worked as a code breaker for Cromwelland later for Charles II after the restoration.

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John Wallis by Sir Godfrey Kneller

Newton first went up to university after the restoration but others of an earlier generation suffered loss of university position for being on the wrong side at the wrong time. John Wilkins (1614–1672), a parliamentarian and Cromwell’s brother-in-law, was appointed Master of Trinity College Cambridge, Newton’s college, in 1659 and removed from this position at the restoration. Wilkins’ Mathematical Magick (1648) had been a favourite of Newton’s in his youth.

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Greenhill, John; John Wilkins (1614-1672), Warden (1648-1659); Wadham College, University of Oxford;

Newton’s political career began in 1689 following the so-called Glorious Revolution, when James II was chased out of Britain by William of Orange, his son-in-law, invited in by the parliament out of fear that James could reintroduce Catholicism into Britain. Newton sat in the House of Commons as MP for the University of Cambridge in the parliament of 1689, which passed the Bill of Rights, effectively a new constitution for England. Newton was not very active politically but he identified as a Whig, the party of his student Charles Montagu (1661–1715), who would go on to become one of the most powerful politicians of the age. It was Montagu, who had Newton appointed to lead the Royal Mint and it was also Montagu, who had Newton knighted in 1705in an attempt to get him re-elected to parliament.

In the standard version of story Newton represents the end of the scientific revolution and Copernicus (1473–1543) the beginning. Religion, politics and war all played a significant role in Copernicus’ life.

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Copernicus, the “Torun portrait” (anonymous, c. 1580), kept in Toruń town hall, Poland.

Copernicus spent the majority of his life living in the autonomous prince-bishopric of Warmia, where as a canon of the cathedral he was effectively a member of the government. Warmia was a Catholic enclave under the protection of the Catholic Crown of Poland but as the same time was geographically part of Royal Prussia ruled over by Duke Albrecht of Prussia (1490–1568), who had converted to Lutheran Protestantism in 1552. Ironically he was converted by Andreas Osiander (1498–1552), who would go on the author the controversial ad lectorum in Copernicus’ De revolutionibus. Relations between Poland and Royal Prussia were strained at best and sometimes spilled over into armed conflict. Between 1519 and 1521 there was a war between Poland and Royal Prussia, which took place mostly in Warmia. The Prussians besieged Frombork burning down the town, but not the cathedral, forcing Copernicus to move to Allenstein (Olsztyn), where he was put in charge of organising the defences during a siege from January to February 1521.  Military commander in a religious war in not a role usually associated with Copernicus. It is an interesting historical conundrum that, during this time of religious strife, De revolutionibus, the book of a Catholic cathedral canon, was published by a Protestant printer in a strongly Protestant city-state, Nürnberg.

The leading figure of the scientific revolution most affected by the religious wars of the age must be Johannes Kepler. A Lutheran Protestant he studied and graduated at Tübingen, one of the leading Protestant universities. However, he was despatched by the university authorities to become the mathematics teacher at the Protestant school in Graz in Styria, a deeply Catholic area in Austria in 1594. He was also appointed district mathematicus.

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Johannes Kepler Source: Wikimedia Commons

In 1598, Archduke Ferdinand, who became ruler of Styria in 1596, expelled all Protestant teachers and pastors from the province. Kepler was initially granted an exception because he had proved his worth as district mathematicus but in a second wave of expulsion, he too had to go. After failing to find employment elsewhere, he landed in Prague as an assistant to Tycho Brahe, the Imperial Mathematicus.

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Tycho Brahe Source: Wikimedia Commons

Once again he, like Tycho, was a Protestant in a Catholic city serving a Catholic Emperor, Rudolf II. Here he soon inherited Tycho’s position as Imperial Mathematicus. However, Rudolf was tolerant, more interested in Kepler’s abilities as an astrologer than in his religious beliefs. Apart from a substantial problem in getting paid in the permanently broke imperial court, Kepler now enjoyed a fairly quiet live for the next twelve years, then everything turned pear shaped once more.

In 1612, Rudolf’s younger brother Archduke Matthias deposed him and although Kepler was allowed to keep his title of Imperial Mathematicus, and theoretically at least, his salary but he was forced to leave Prague and become district mathematicus in Linz. In Linz Kepler, who openly propagated ecumenical ideas towards other Protestant communities, most notably the Calvinists, ran into conflict with the local Lutheran pastor. The pastor demanded that Kepler sign the Formula of Concord, basically a commitment to Lutheran theology and a rejection of all other theologies. Kepler refused and was barred from Holy Communion, a severe blow for the deeply religious astronomer. He appealed to the authorities in Tübingen but they up held the ban.

In 1618 the Thirty Years War broke out and in 1620 Linz was occupied by the Catholic army of Duke Maximilian of Bavaria, which caused problems for Kepler as a Lutheran. At the same time he was fighting for the freedom of his mother, Katharina, who had been accused of witchcraft. Although he won the court case against his mother, she died shortly after regaining her freedom. In 1625, the Counterreformation reach Linz and the Protestants living there were once again persecuted. Once more Kepler was granted an exception because of his status as Imperial Mathematicus but his library was confiscated making it almost impossible for him to work, so he left Linz.

Strangely, after two years of homeless wandering Kepler moved to Sagen in Silesia in 1628, the home of Albrecht von Wallenstein the commander of the Catholic forces in the war and for whom Kepler had interpreted a horoscope much earlier in life. Kepler never found peace or stability again in his life and died in Ulm in 1630. Given the turbulence in his life and the various forced moves, which took years rather than weeks, it is fairly amazing that he managed to publish eighty-three books and pamphlets between 1596 and his death in 1630.

A younger colleague of Kepler’s who also suffered during the Thirty Years’ War was Wilhelm Schickard, who Kepler had got to know during his time in Württemberg defending his mother. Schickard would go on to produce the illustrations both Kepler’s Epitome Astronomiae Copernicanae and his Harmonice Mundi, as well as inventing a calculating machine to help Kepler with his astronomical calculations. In 1632 Württemberg was invaded by the Catholic army, who brought the plague with them, by 1635 Schickard, his wife and his four living children, his sister and her three daughters had all died of the plague.

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Wilhelm Schickard, artist unknown Source: Wikimedia Commons

As I have pointed out on numerous occasions Galileo’s initial problems in 1615-16 had less to do with his scientific views than with his attempts to tell the theologians how to interpret the Bible, not an intelligent move at the height of the Counterreformation. Also in 1632 his problems were very definitely compounded by the fact that he was perceived to be on the Spanish side in the conflict between the Spanish and French Catholic authorities to influence, control the Pope, Urban VIII.

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Galileo Portrait by Ottavio Leoni Source: Wikimedia Commons

I will just mention in passing that René Descartes served as a soldier in the first two years of the Thirty Year’s War, at first in the Protestant Dutch States Army under Maurice of Nassau and then under the Catholic Duke of Bavaria, Maximilian. In 1620 he took part in the Battle of the White Mountain near Prague, which marked the end of Elector Palatine Frederick V’s reign as King of Bohemia. During his time in the Netherlands Descartes trained as a military engineer, which was his introduction to the works of Simon Stevin and Isaac Beeckman.

Frans_Hals_-_Portret_van_René_Descartes

René Descartes Portrait after Frans Hals Source: Wikimedia Commons

We have now gone full circle and are almost back to Isaac Newton. One interesting aspect of these troubled times is that although the problems caused by the wars, the religious disputes and the associated politics caused major problems in the lives of the astronomers and mathematicians, who were forced to live through them, and certainly affected their ability to carry on with their work, I can’t somehow imagine Copernicus working on De revolutionibus during the siege of Allenstein, the scholars themselves communicated quite happily across the religious divide.

Rheticus was treated as an honoured guest in Catholic Warmia although he was a professor at the University of Wittenberg, home to both Luther and Melanchthon. Copernicus himself was personal physician to both the Catholic Bishop of Frombork and the Protestant Duke of Royal Prussia. As we have seen, Kepler spent a large part of his life, although a devoted Protestant, serving high-ranking Catholic employers. The Jesuits, who knew Kepler from Prague, even invited him to take the chair for mathematics at the Catholic University of Bologna following the death of Giovanni Antonio Magini in 1617, assuring him that he did not need to convert. Although it was a very prestigious university Kepler, I think wisely, declined the invitation. The leading mathematicians of the time all communicated with each other, either directly or through intermediaries, irrespective of their religious beliefs. Athanasius Kircher, professor for mathematics and astronomy at the Jesuit Collegio Romano, collected astronomical data from Jesuits all over the world, which he then distributed to astronomers all over Europe, Catholic and Protestant, including for example the Lutheran Leibniz. Christiaan Huygens, a Dutch Calvinist, spent much of his life working as an honoured guest in Catholic Paris, where he met and influenced the Lutheran Leibniz.

When we consider the lives of scientists we should always bear in mind that they are first and foremost human beings, who live and work, like all other human beings, in the real world with all of its social, political and religious problems and that their lives are just as affected by those problems as everybody else.

 

 

 

 

 

 

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