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Journalists getting the facts wrong in the 19th century

One of the joys of having an extensive twitter stream is the unexpected titbits that it throws up from time to time. Recently Lee Jackson[1] (@VictorianLondon) posted this small newspaper cutting from The Times for the 2nd May 1862.

This is an excerpt from an account of the 1862 Great London Exposition not to be confused with the more famous Crystal Palace Exhibition of 1851. This Exposition was held in a building especially constructed for the purpose in South Kensington, where the Natural History Museum now stands.

Panoramic view of the International Exhibition of 1862 in South Kensington, London
Source: Wikimedia Commons

A twenty-one acre construction designed by Captain Francis Fowke (1823–1865) of the Royal Engineers, it was supposed to be a permanent structure but when parliament refused to buy the building after the Exposition closed it was demolished and the materials used to build Alexandra Palace. The building cost £300,000 paid for out the profits of the 1851 Exhibition. Fowke also produced the original plans for the Natural History Museum but died before they could be realised. His plans were modified by Alfred Waterhouse, the new architect, when the museum was finally constructed in 1870.

Francis Fowke (1823-1865)
Source: Victoria & Albert Museum

The main aim of the Exposition, which ran from 1 May to 15 November attracting over six million visitors, was to present the latest technological advances of the industrial revolution, hence the presence an engine of Charles Babbage as described in the cutting. However the author of the piece has got his facts wonderfully mixed up.

The author introduces Charles Babbage by way of his notorious disputes with the street musicians of London for which he was better known than for his mathematical and technical achievements and which I blogged about several years ago. We then get told that the Exposition is displaying “Mr Babbage’s great calculating machine, which will work quadrations and calculate logarithms up to seven places of decimals.” All well and good so far but then he goes on, “It was the account of this invention written by the late Lady Lovelace – Lord Byron’s daughter –…” Anybody cognisant with the calculating engines designed by Charles Babbage will have immediately realised that the reporter can’t tell his Difference Engines from his Analytical Engines.

The calculating machine capable of calculating logarithms to seven places of decimals, of which a demonstration module was indeed displayed at the 1862 Exposition, was Babbage’s Difference Engine. The computer described by Lady Lovelace in her notorious memoire from 1842 was Babbage’s Analytical Engine of which he only constructed a model in 1871, nine years after the Exposition. This brings us to Messrs Scheutz of Stockholm.

Difference Engine No. 1, portion,1832
Source: Science Museum London

Analytical Engine, experimental model, 1871
Source: Science Museum London

Per Georg Scheutz (1785-1873) was a Swedish lawyer and inventor, who invented the Scheutzian calculation engine in 1837 based on the design of Babbage’s Difference Engine.

Per Georg Schutz
Source: Wikimedia Commons

This was constructed by his son Edvard and finished in 1843. An improved model was created in 1853 and displayed at the World Fair in Paris in 1855. This machine was bought by the British Government in 1859 and was in fact displayed at the 1862 Exposition but had apparently been removed by the time the Time’s reporter paid his visit to South Kensington. Scheutz’s machine gives a lie to those who claim that Babbage’s Difference Engine was never realised. Scheutz constructed a third machine in 1860, which was sold to the American Government.

The third Difference engine (Scheutz No. 2) built by Per Georg Scheutz, Edvard Scheutz and Bryan Donkin
Source: Science Museum London

It would seem that journalist screwing up their accounts of scientific and technological advances has a long history.




[1] You should read his excellent Dirty Old London: The Victorian Fight Against Filth, Yale University Press, Reprint 2015

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A very special book

In 1543 the printer/publisher Johannes Petreius published Nicolaus Copernicus’ De revolutionibus orbium coelestium, the first mathematical description of a heliocentric system for the then known cosmos, in Nürnberg. Initially appearing with little resonance, more than two hundred years later the great, German, enlightenment philosopher Immanuel Kant thought that its publication signalled the greatest ever change in humanities perception of its own place in the cosmos. Today many historians of science regard it as the most important scientific publication ever. Although I object to the use of superlatives in the history of science, I do think that it is one of the most significant scientific publication of the Early Modern Period.

Title page of the first edition of De revolutionibus
Source: Wikimedia Commons

It is not actually known how many copies Petreius printed of that first edition but Owen Gingerich[1], the greatest authority on the subject, estimates that the first edition was probably about five hundred copies of which about three hundred still exist. A small number of the surviving copies of the first edition were given by Petreius to selected people as presents with a hand written dedication from himself. One of these resides in the University of Leipzig library. The Leipzig De revolutionibus has the following dedication:

Hieronymo Schr[ei]ber Petreus dedit 1543

Hieronymus Schreiber was born in Nürnberg; his date of birth is unknown. He is thought to have attended the Egidien Gymnasium in Nürnberg, where he would have been taught mathematics by Johannes Schöner. Schöner later dedicated an edition of Peuerbach’s Tractatus super propositiones Ptolemaei, that he edited and Petreius published in 1541, to him. In 1532 Schreiber matriculated at the University of Wittenberg, in the same year as Georg Joachim Rheticus. When Rheticus took his sabbatical in 1539, which lead him to go off to Frombork and bring back the manuscript of De revolutionibus to Nürnberg, it was Schreiber who took over his teaching duties in Wittenberg, teaching mathematics to the undergraduates there. It was almost certainly for this work that Petreius rewarded him with a personally dedicated copy of De revolutionibus.

When Rheticus left Wittenberg in 1542, to take up the post of mathematics professor in Leipzig, his chair was not awarded to Schreiber but to the Nürnberger mathematician Erasmus Flock (1514–1568), another of Schöner’s pupils. Schreiber left Wittenberg for Italy and died in 1547 during a period of study in Paris.

In 1598 Schreiber’s copy of De revolutionibus came into the possession of the young Johannes Kepler, together with two other astronomy books that had belonged to Schreiber. Quite how Kepler acquired these books is not known.

The book nowadays known as the Kepler De revolutionibus contains some very interesting marginalia. Schreiber added one of the most complete collections of corrections to the text, not only the errata contained on the official errata sheet but also many others. Schreiber’s most interesting annotation is the addition of the name Andreas Osiander above the Ad lectorum, which prefaces the book. Kepler draws attention to this on the back of the flyleaf and it was Kepler who first made Osiander’s authorship of the Ad lectorum general knowledge, thereby sealing his fate as ‘the greatest villain in the history of science.’ Kepler added comparatively few comments in the margins after he acquired the book but those that he did add show his progress as he worked his way through Copernicus’ opus.

The value of collectable works from the history of science depends not only on the works themselves but also on their provenances, who were the owners and what did they write in the margins? First editions of De revolutionibus rarely appear for sale but when one that had belonged to John Greaves (1602–1652) the Savilian Professor of Astronomy at Oxford was auctioned some years back it sold for almost 2.5 million dollars. Should Kepler’s De revolutionibus, with its rare handwritten Petreius dedication, ever come on to the open market, which I doubt it will, I suspect the sky’s the limit, as they say.

Last Sunday I took a trip to Nürnberg to the Germanisches National Museum to see their new exhibition celebrating The Luther Year (it’s five hundred years since Luther made his 95 Theses public), Luther, Kolumbus und die Folgen: Welt im Wandle 1500 – 1600. This exhibition had lots of very nice stuff from the histories of astronomy, cartography and exploration and is highly recommended if you are in the area before the beginning of November when it ends. I was happily trundling round the exhibition giving detailed background information to my companion, as is my wont, when I rounded a corner and espied a glass cabinet with copies of De revolutionibus. One of the ironies of history is that although the book was printed in the city, Nürnberg does not possess a first edition of De revolutionibus, so imagine my surprise and delight when I realised that the first edition sitting in the cabinet, next to the museum’s own second edition (Basel 1561), was in fact the Kepler De revolutionibus, on loan from the University of Leipzig library – a very special book indeed.

[1] Much of the information in this post is taken from Owen Gingerich’s excellent An Annotated Census of Copernicus’ De Revolutionibus (Nuremberg, 1543 en Basel, 1566), Brill, Leiden-Boston-Koln, 2002

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A very innovative early scientific printer/publisher

It is a commonplace amongst historians that the invention of movable type, and through it the advent of the printed book, in the middle of the fifteenth century, was one of the principal driving forces behind the emergence of modern science in the Early Modern Period. However, although historians of science pay lip service to this supposedly established fact very few of them give any consideration to the printer/publishers who produced those apparently so important early books on science, medicine and technology. Like the technicians and instrument makers, the printer/publishers, not being scientist, are pushed to the margins of the historical accounts, left to the book historians.

Here at the Renaissance Mathematicus I have in the past featured Regiomontanus, considered to be the very first printer/publisher of science, Johannes Petreius the publisher of Copernicus’ De revolutionibus amongst numerous other scientific works and Anton Koberger around 1500 the world’s biggest printer/publisher and the man who produced the first printed encyclopaedia, The Nuremberg Chronicle. Today I want to turn my attention to a less well-known but equally important printer/publisher of scientific texts, who was responsible for several significant innovations in book production, Erhard Ratdolt.

Erhard Ratdolt was born in Aichach in Bavaria in 1459 or 60 the son of the carpenter Erhard Ratdolt and wife Anna. Erhard apprenticed as a carpenter and a maker of plaster figures. At the age of fifteen, according to his own account, he travelled to Venice, where he set up a printer/publisher office together with Bernhart Pictor a painter from Augsburg and Peter Loslein from Langenzenn, a small town near Nürnberg, in 1476.[1] The printing house was one of the earliest in Venice, where Johannes de Spira had set up the first one in 1469. By 1480 Venice had become to main centre for book production in Europe It seems that Ratdolt ran the business, whilst Pictor was responsible for the book decoration and Loslein for the text and copyediting. Both Pictor and Loslein had left the publishing house by 1478 leaving Ratdolt as the sole proprietor. Ratdolt’s two partners were probably victims of the plague, which wiped out eleven of the twenty-two printer/publishing establisments existing in Venice in 1478.

Their first publication was Regiomontanus’ Calendar, published in Latin and Italian in 1476 and in German in 1478. This book already contained several innovations. Ratdolt and his partners introduced the concept of printed ornamental borders for the pages of their books, a style that became typical for Renaissance books. They also introduced the first modern title page! It almost certainly seems strange to the modern book reader but the volumes printed in the first twenty or so years of book printing didn’t have title pages, as we know them. Ratdolt’s Regiomontanus Calendar was the first book to have a separate page at the beginning of the volume giving place, date and name of the printer. It was also the first book to have its publication date printed in Hindu-Arabic numerals and not in Roman ones. It would be some time before title pages of the type introduced by Ratdolt became common.

Calendarius by Regiomontanus, printed by Erhard Ratdolt, Venice 1478, title page with printers’ names
Source: Wikimedia Commons

In terms of the sciences Ratdolt’s most important work was the first printed edition of Euclid’s Elements, which he published in 1482. Here the innovation, a very major one was the inclusion of illustrations in the text. I say within the text but in fact the book was printed with very wide margins and the geometrical diagrams were printed next to the relevant text passage in these margins.

A page with marginalia from the first printed edition of Euclid’s Elements, printed by Erhard Ratdolt in 1482
Folger Shakespeare Library Digital Image Collection
Source: Wikimedia Commons

Another of Ratdolt’s innovations was the introduction of first two-coloured printing and then over time building up to books printed in as many as five colours and also printing with gold leaf.

Diagram, showing eclipse of the moon; woodcut, printed in three colours, from Sphaericum opusculum by Johannes de Sacro Bosco, printed by Erhard Ratdolt, Venice 1485
Source: Wikimedia Commons

In 1486 Ratdolt returned to Bavaria and set up a new publishing house in Augsburg at the invitation of the bishop and it was here that he introduced his next innovation. He is the earliest known printer/publisher to issue a printer’s type specimen book, in his case a broadsheet, displaying the fonts that he had available to print his wares. Upon his return to Augsburg Ratdolt was the first to introduce the Italian Rotunda font into Germany. He was also one of the earliest printers to offer Greek fonts for printing. Another of his innovations was the dust jacket. Like most other printer/publishers in the first half-century of book printing Ratdolt’s output in Augsburg was mostly religious works, although he did print some astrological/astronomical volumes. Ratdolt’s output declined from 1500 onwards but between 1487 and his death in 1522 his publishing house issued some 220 volumes.

Wappen des Bischofs Johann von Werdenberg, in der Widmung des Augsburger Breviers, 1485
Source: Wikimedia Commons

Given his youth when he left Bavaria for Venice Ratdolt’s contributions to the development of early book printing were truly remarkable. Even if his original partners were older and had started this chain of innovation, Ratdolt was still a teenager when they both disappeared from the business (died?) and the innovations continued when he was running the business alone.

Two interesting historical questions remain open concerning Ratdolt’s activities as a printer/publisher. We actually have no idea when, where or how he learnt the black art, as printing was known in that early period. The second problem concerns another early printer of scientific texts, Regiomontanus, and his connection to Ratdolt. The first book that Ratdolt published was Regiomontanus’ Calendar an important astrological/astronomical text that was something of a fifteenth-century best seller. The manuscript of the Euclid that Ratdolt published was one of the ones that Regiomontanus had discovered in Northern Italy when he was in the service of Cardinal Bessarion, as his book collector between 1461 and 1467. This raises the question, how did Ratdolt come into possession of Regiomontanus’ manuscripts?

Some earlier writers solved both questions by making Ratdolt into Regiomontanus’ apprentice in his publishing house in Nürnberg. The theory is not so far fetched, as Aichach is not so far away from Nürnberg and Ratdolt moved to Venice at about the same time as Regiomontanus disappeared and is presumed to have died. Unfortunately there is absolutely no evidence whatsoever to support this theory. Also given Regiomontanus’s renown at the time of his death, not just as a mathematical scholar but also as a printer/publisher, if Ratdolt had been his apprentice he would surely have advertised the fact in his own printing endeavours. I suspect that we will never know the answers to these questions.






[1] On a personal note I spent my first four years in Germany living just down the road from Langenzenn, where I spent most of my free time.

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“I went on holiday and I haven’t gone back home yet”

Today is the eighth anniversary of the founding of The Renaissance Mathematicus and, as on a couple of similar occasions in the past, I have decided to regale you with something biographical[1]. This is quite literally a tale of sex and drugs and rock’n’roll, so if you have any objections, moral or otherwise, to reading about such things or to the people who indulge or have indulged in them then I suggest you stop reading now.

In what follows I intend to tell the tale of how I came to live in Germany, where I have substantially now spent more than half of my life and where, all things being equal, I shall probably die. You might ask what my coming to live in Germany has to do with my blogging about the history of science but the connection is really quite direct. If I hadn’t come to Germany in 1980, I wouldn’t have ended up studying the history and philosophy of science, as a mature student, at Erlangen University and although I never completed my master’s degree, due to mental health problems, going on to become a sort of semi-professional historian of science and then a history of science blogger. But back to the beginning.

It all started in the summer 1977 when I moved back to Cardiff from Malmö in Sweden (that’s another story!). D (all the other people in this story will only be identified by their initials) had started constructing a yurt or ger, the round tents used as dwellings by the nomads of Central Asia, most notably the Mongolians.

A ger sits on the Steppes near Mandalgovi
Source: Wikimedia Commons

Why D had decided to construct a yurt I never quite fathomed but it was a typical D project. D had a good degree in biology but had decided instead of becoming a biologist, to smoke dope and indulge in moderately crazy projects. The projects were financed by the collective’s dope dealing activities. The collective consisted of those who lived in number 24, where D was at home, a rotating group of about twelve and various friends and acquaintances, of which I was one, bringing the total to somewhere around thirty. Many members of the collective were musicians. One member of the collective would buy dope in wholesale quantities and then others would distribute it at low profit margins to a relatively large network throughout the city. The professional dealers didn’t like us because we seriously undercut their prices but we had the protection of the big guys, who found our ‘socialist’ dealing somehow charming. I was a distributer, my only profit being my own not inconsiderable consumption. I got to smoke for free and my ‘customers’ enjoyed low priced dope. Everybody was happy. The central profits were used to finance projects like the yurt or the collective’s long wheel based Land Rover.

In the evenings members of the collective would come together in the large ground flour living room in number 24, get totally wasted and then indulge in long musical jam sessions, playing blues, folk, rock and often long open-ended snake dance instrumental jams. K & C were a couple who were both excellent guitarists who also sang and C, an American medical student, who had a beautiful voice like Joanie Mitchell also played flute. A, who had a degree in philosophy but who had gone off the rails and now ran a whole food shop, played saxophone and clarinet. Both B and JC were professional base players and were also excellent guitarists. B had a double music degree in classical guitar and composition. I played blues harp and jaw harp and almost everyone played percussion. Those sessions often ran for hours. There was also a formal house band built around K & C, which would occasionally play public gigs.

Various members of the collective, including me, were involved in constructing the wooden frame of the yurt and N, who worked as a theatre company seamstress sewed the roof and wall coverings out of lorry tarpaulins on an industrial sewing machine. We road tested the yurt on a very stoned, long weekend in Mid Wales in autumn during the magic mushroom season. It proved to be very reliable.

Mongolian Ger: starting to place roof poles
Source: Wikimedia Commons

In 1979 we decided to take yurt, house band and whoever wanted to come to the summer solstice free festival at Stonehenge. We loaded the yurt onto the Land Rover together with a lot of serious camping equipment, saws, axes, cooking pots etc. and set off for the full tens days of sex and drugs and rock’n’roll on Salisbury Plain. All together we were about thirty people, the yurt was big enough to sleep up to twenty and several people, myself included, took their own tents.

Surprisingly several of this bunch of dope smoking hippies had been boy scouts in their youth, including me, and we set a very professional camp site with a large fire pit on which we not only cooked food for all of our own group, funded from a communal kitty, but cooked and sold food to other attendees. A lot of drugs were consumed and a lot of music was played. On the afternoon before the solstice A and I took off across the festival site selling some first class acid that we had acquired. In the evening A, B and I dropped some acid and taking our respective instruments went off to a tepee with a generator to take part in an amplified jam session. We played raga rock, flying on acid for several hours until the generator ran out of petrol.

I wound my way back to our campsite in the early hours of the solstice dawn to join a fairly large gathering that had assembled around our fire pit to greet the solstice. One of those sitting around the glowing embers was a young German lady, AZ. We got into conversation and as the party wound down we retired to my tent. The following day AZ moved on in her Interrail trip around Britain but not before we had exchanged addresses. Over the next year we exchanged occasional letters and postcards.

Your author at Stonehenge Free Festival 1979 sawing firewood courtesy of AZ
I have no idea who the young lady on the right is!

In the summer of 1980 I was at something of a lose end in my personal life that didn’t seem to be going anywhere in particular. I was busy rewiring the photo and graphics studio of a friend one afternoon when I decided that what I needed was a holiday. Due to the work I was doing I knew that I would have some funds and fell to thinking where I could possibly go. The first two thoughts I had were that I could visit AZ in Germany or I could take a trip to Morocco, the destination of choice of various of my traveller friends at the time. Travellers were people who would work for six months or a year saving as much of their earnings as possible and then set off with a rucksack and sleeping bag to parts exotic for as long as they could make the money last. I had several such friends in those days but I wasn’t a traveller. When I got home to my flat on that evening there was a postcard from AZ who was on holiday in Morocco! I kid you not this really did happen.

Never one to ignore a wink of fate, in particular not one that obvious, I set off in September to hitch to Morocco via Southern Germany. I took a ferry to Hoek van Holland because I wanted to visit a friend who had moved there. Nobody had his address but I was assured by his brother that he was in the local telephone book. If he was, I couldn’t find him and so I set out to hitch down to Nürnberg in the vicinity of which AZ was living. It took two days including a night spent sleeping on the periphery of Frankfurt Airport. Not a quiet night. I had intended to stay just a couple of days in Franconia but ended up staying two weeks and getting to know a great crowd of people. When I started out again I hitched down through Austria to Florence in Northern Italy. From here I moved across Italy into Southern France winding my way across the south into Spain. Here I got picked up by a group of French Canadians with whom I spent a couple of crazy days. Working my way further south at snails pace, Spain was not a good country for hitch hiking in those days, I finally arrived in Algeciras and took the ferry to Ceuta, where I met a Swiss hippy who offered a sort of unofficial taxi service down to Marrakesh, which I took.

Having spent several days in Marrakesh I moved on to Meknes, which at that time had the only functioning mosque that one could visit as a non-Muslim. Here I had two very nice experiences. In order to visit the mosque you have to be shown round by a guide. I got shown round, together with two German tourists, by a young Moroccan student. The student only spoke French and the Germans only spoke English so I ended up acting as translator, because of this a got my guided tour for free, the student being thankful for my services. The student then took me to a student café where I spent the evening in the company of about twenty young Moroccans, mostly students, dinking mint tea and smoking kief. The young students made me feel very much at home and those were the happiest hours that I spent in Morocco.

In classic style my money began to run out and I got sick, some sort of flu like virus, so I began to head back to Europe. I was feeling shit and was very, very low on funds by the time I reached Madrid and was wondering how I could get back home when I met a German who had been deported from Morocco and had a one-way train ticket to Munich paid for by the German Embassy in Morocco. He sold me his train ticket for most of the cash that I had left and I rode the train back to Germany getting off in Nürnberg and going back to AZ’s.

My plan was to get well, find some casual work and earn enough money to get back to the UK. Having recovered my health, speaking no German I went down the honoured George Orwell route and got a job as a dishwasher in a local hotel. Here I had the best name-dropping experience of my entire life. The hotel manager was rather chuffed at having a genuine white British dishwasher, all of my colleagues where Indians, and would come and practice his English on me. One day I came into work at 7 am and he rushed to meet me asking if I knew who had slept in his hotel that night? I of course had no idea and playing the required role of straight man responded, no who? He burst out excitedly, “Roy Jenkins, President of the European Commission!” I, without thinking at all about what I was saying, “Oh, I went to school with his children”. His face dropped a mile, trumped by a mere dishwasher. He turned and walked away without saying a word.

In December I decided that I was going to stay in Germany and I’m still here thirty-seven years later. If people ask how I came to live in Germany I always answer, as I said above, “I went on holiday and I haven’t gone back home yet”, which is the simple truth.



[1] This also fulfils a request made by some commentators on my 2016 Winter Solstice post.


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Telling the time at night

The first humans almost certainly followed a pattern of being active during daylight and resting or sleeping during the night, if the latter with one eye open, because of potential danger. As humanity developed it also began to develop the potential for tracking time. During the day following the path of the sun is the first step and this eventually leads to the use of shadows to track and to express times. However at night the sun is no longer visible and it is rare for the moon to be bright enough cast shadows and these are fairly useless for tracking time. So how do you track time at night?

If you look into a clear night sky the heavens are full of stars, still visible in the days before the invention of street lighting and light pollution. At first there seems to be no order to this extensive panorama of bight points but for those living in the northern hemisphere if you look due north you will eventually perceive that there is one star, Polaris the North or Pole Star[1], that appears to remain stationary whilst the stars and groups of stars surrounding it appear to circle it as the night proceeds. As we know, the stars are stationary it is the earth that is revolving on its axis. The stars and groups of stars closest to Polaris appear to circle it completely but those further away rise up over the horizon cross the sky and then set under the horizon on the other side of the heavens.

A time exposure showing the path of the circumpolar star with Polaris in the centre
Photo: Ashley Dace
Source: Wikimedia Commons

The ancient Egyptians used this phenomenon of the rising stars and groups of stars, (known as heliacal rising wrong see comments!) to tell the time at night. They identified thirty-six stars or groups of stars, known as the Decans (because a new one appeared over the horizon every ten days), for this purpose to cover the whole year, because of the tilt of the earth’s axis different stars or groups of stars rise on different nights. On any given night twelve of these chosen stars or groups of stars rose over the horizon at regular interval during the night giving the Egyptian astronomer/priests a clock with which to divide the night into twelve periods. Again, because of the tilt of the earth’s axis and the varying seasons the length of the nights varies and with them the length of the divisions. With time the Egyptians also divided the daytime into twelve segments giving us our twenty-four hour day.

Diagonal star table’ from the late 11th Dynasty coffin lid; found at Asyut, Egypt. Roemer- und Pelizaeus-Museum Hildesheim
Source: Wikimedia Commons

Later cultures measured the hours of the night using other methods such as water clocks (or clepsydra) and candle clocks. These of course because of their imperfections only give approximate hourly divisions but this was more than accurate enough for those using them, who did not yet possess our obsession of living by the clock.

An early 19th-century illustration of Ctesibius’s (285–222 BC) clepsydra from the 3rd century BCE. The hour indicator ascends as water flows in. Also, a series of gears rotate a cylinder to correspond to the temporal hours.
The illustrator was probably John Farey, Jr. (1791–1851).
Source: Wikimedia Commons


Al-Jazari’s candle clock in 1206
Source: Wikimedia Commons

However others, like the ancient Egyptians, continued to use star clocks. Mariners who regularly sailed the same routes grew to know the night sky and could by observing the position of a given circumpolar star or group of stars approximately determine the hours of the night. This form of using the circumpolar stars as the hands of a clock was put into use in the Middle Ages by the invention of an astronomical instrument known as a nocturnal or nocturlabium.

Girolamo della Volpaia (ca. 1530-1614)
Nocturnal and horary quadrant, 1568
Florence, Istituto e Museo di Storia della Scienza, inv. 2503
The horary quadrant is used to determine the time during daylight

The nocturnal is a circular, usually brass, instrument with a hole in the middle. It has two discs or dials and an indicator arm or pointer that sticks out beyond the outer dial. The outer dial is marked with the months of the year and the inner dial with the hours of the day. The inner dial also has a pointer. Nocturnals are constructed and calibrated for a specific circumpolar star. To tell the time the inner disc is rotated until its pointer points at the right month. Then the instrument is raised to the observer’s eye and the Pole Star is sighted through the central hole. The pointer or indicator arm is then adjusted until it lies on the position of the calibrated star or star group. The time can now be read off on the inner dial. Small nocturnals are usually only calibrated in hours, larger instruments are accurate to a quarter of an hour.

Medieval diagram explaining how to use a nocturnal. Peter Apian I think!
Source Wikimedia Commons

[1] Because the stars are actually moving very slowly relative to the earth the star that has been perceived as the Pole Star over the millennia has actually changed.


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In history getting labels right is important

This is a post about history in general but it applies just as much to the history of science. I have over the years written several posts about the problems of attributing nationalities or even countries of origins to historical figures and this post discusses another example of this, where the attributions are about ahistorical as you can get. What is it this time that has piqued my ire? It was the title of an article in The Guardian that contains historical attributions that are ahistorical, anachronistic and quite frankly xenophobic.

Did Dutch hordes kill off the early Britons who started Stonehenge?

Strong words, strong claims, so what is wrong with this title? The article is about the spread into Britain from the continent of the so-called Beaker folk, a European wide Neolithic-Bronze Age culture that existed from around 2900 BCE to 1800 BCE. Archaeologists and prehistorians define cultures through characteristic behaviours or artefacts. The Beaker culture is so named because of the habit of burying their dead with distinctive ceramic pots or beakers. This cultural group moved into Britain around 2500 BCE and the article claims that DNA analysis has shown that the previous inhabitants disappear out of the genetic record to be replaced by the newcomers. All well and good so what’s my beef?

First off, the title suggests that the original population were killed off by invading Europeans but the previous population were, like the Beaker people, themselves European immigrants, as had and have been all of the inhabitants of the British Isles. It is not known when exactly the Neolithic culture that started building Stonehenge arrived in Britain but they were with certainty not Britons! One moment there! If they are living in Britain they are Britons, right? Wrong!

The name Britons for inhabitants of this island derives from the reports of the fourth-century Greek explorer Pytheas of Massalia (that’s Marseille). Pytheas supposedly circumnavigated the island and referred to its inhabitants as Pretani and the island as Prettanikē; these are the origins of the words Briton and Britain. The words he is using are thought to be transliterations into Greek of the names used by the inhabitants that Pytheas met, who are not even Beaker people but members of a later wave of immigrants the Celts. We don’t have a name for the Neolithic folk who started building Stonehenge but they were not Britons.

We have the same problem with the Beaker people being called Dutch in the title. There were settlements of the Beaker people all over Europe but they thought to have originated in what is now Spain. The group that crossed the Channel onto the British Island are said by the historical geneticists to have come from what is now the Northern Netherlands but that in no way makes them Dutch.

The Dutch are, like the English, a Low German dialect speaking Germanic folk. They originated in what is today Southern Scandinavia and Northern Germany and because of climate change moved southwards into the Netherlands between 850 and 750 BCE so once again long after the Beaker culture had died out.

What we actually have is one wave of immigrants from the European continent being supplanted by another wave of immigrants from the European continent. The former are not Britons and the latter are not Dutch and to claim that they were, is a massive historical distortion and has, as I said at the beginning a strong stench of xenophobia. The British Isles has on and off, since about 42,000 years BP (before the present), been occupied by successive waves of immigrants from the European continent the last being the Normans, a Norse culture residing in France, in 1066 CE.

Almost all areas in the world have similar histories of habitation and historians or people writing historical articles should be very, very careful when attaching labels to peoples or geographical areas in their writings.


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Bringing the heavens down to earth

The Frisian Protestant pastor and amateur astronomer, David Fabricius, was beaten to death by one of his parishioners on 7 May 1617. Because he corresponded with both Tycho Brahe and Johannes Kepler and was quite a significant figure in Early Modern astronomy the Society for the History of Astronomy had a short post on Facebook commemorating his death on last Sunday, which contained the following claim:

David Fabricius was, following Galileo’s lead, one of the early users of the telescope in astronomy[1]

This claim contains two factual errors. The first is that it was Johannes, David’s son, who introduced the telescope into the Fabricius household and not David, although David soon joined his son in his telescopic observations. I’ll explain further later.

The Fabricii, father and son, remain largely unknown to the world at large but a monument to them both was erected in the churchyard in Osteel, where David had been village pastor, in 1895.

The second error is more serious because it indirectly perpetuates a widespread myth concerning the introduction of the telescope into astronomy and Galileo’s role in it. There is a popular perception that Galileo, and only Galileo, had the genius, the wit, the vision to realise that the newly invented telescope could be used as an astronomical instrument and that he singlehandedly pioneered this new discipline, telescopic astronomy. This is of course complete rubbish and seriously distorts the early history of the telescope in astronomy and does a major disservice to all of the others who contributed to that early history. I will admit to having done a small fist pump when I read the following in John Heilbron’s Galileo biography:

The transformation of the Dutch gadget into an instrument powerful to discover novelties in the heavens did not require a Galileo. His unique strength lay in interpreting what he saw.[2]

That the telescope could be used as an astronomical instrument was recognised during its very first public demonstration by its inventor, the German/Dutch spectacle maker Hans Lipperhey, which took place at the court of Prince Maurice of Nassau in Den Haag during the Dutch-Spanish Peace Conference on an unknown day between 25 and 29 September 1608. We have a detailed account of this demonstration from a French flyer or newsletter describing the first visit of the Ambassador of Siam to Europe, the Ambassador being present at the demonstration. Through this flyer the news of the new invention spread rapidly throughout Europe. Amongst the other descriptions of the wonderful abilities of this “…device by means of which all things at a very great distance can be seen as if they were nearby, by looking through glasses…” we can read the following:

The said glasses are very useful at sieges & in similar affairs, because one can distinguish from a mile’s distance & beyond several objects very well, as if they are near & even the stars which normally are not visible for us, because of the scanty proportion and feeble sight of our eyes, can be seen with this instrument. [my emphasis]

The first astronomer to build and use a telescope as an astronomical instrument was Thomas Harriot, who drew a sketch of the moon using a telescope on 26 July 1609 before Galileo even had a telescope.

Thomas Harriot’s 1609 telescopic sketch of the moon

This of course raises the question where Harriot obtained his knowledge of this instrument. In the early phase of the telescopes existence it became a common habit to present heads of state and other worthies telescopes as presents. In England James I (VI of Scotland) was presented with one at the end of an elaborate masque created for the occasion by Ben Jonson, the Renaissance playwright. The telescope was obtained from the United Provinces through the offices of Cornelis Drebbel, the Dutch inventor and scholar, who was employed at James’ court. This telescope was probably Harriot’s, who enjoyed good connections to court circles, introduction to the instrument.

Portrait often claimed to be Thomas Harriot (1602), which hangs in Oriel College, Oxford. Source: Wikimedia Commons

Harriot did not observe alone. In London he observed together with his instrument maker Christopher Tooke in London, whilst Harriot’s pupil the landowner and MP, Sir William Lower observed in Wales, together with his neighbour John Prydderch, with a telescope made by Harriot and Tooke. Each pair took turns in observing comparing their results and then Harriot and Lower compared results by letter. This meant that they could be reasonably certain that what they had observed was real and not some optical artefacts produced by the poor quality of the lenses they were using. So here we have four telescopic astronomical observers independent of Galileo’s activities.

In Franconia Simon Marius also built and used telescopes in 1609, at the time unaware of the similar activities of Galileo in Padua. As I have written in another blog post Marius discovered the four largest moons of Jupiter just one day later and independently of Galileo. Marius also made the first telescopic observations of the Andromeda Nebula, significant because the Andromeda Nebula would later become the first galaxy to be recognised as a galaxy outside of our galaxy.

Simon Marius frontispiece from his Mundus Jovialis

Another telescopic pioneer in Southern Germany was the Jesuit astronomer in Ingolstadt, Christoph Scheiner, who famously became embroiled in a dispute with Galileo over who had first observed sunspots with a telescope and what exactly they were.

Christoph Scheinet (artist unknown)

The dispute was rather pointless, as Harriot had actually observed sunspots earlier than both of them and Johannes Fabricius, to whom we will turn next, had already published a report on his sunspot observations unknown to the two adversaries. Christoph Scheiner and his assistant, another Jesuit astronomer, Johann Baptist Cysat, would go on to make several important contributions to telescopic astronomy.

Johann Baptist Cysat, holding a Jacob’s staff

Johannes Fabricius brought his telescope home from the University of Leiden, where he had almost certainly learnt of this instrument through the lectures of Rudolph Snel van Royan, professor of mathematics and father of the better know Willibrord Snel of Snell’s law of refraction fame. Rudolph Snel van Royan was probably the first university professor to lecture on the telescope as a scientific instrument already in 1610.

Rudolph Snel van Royan
Source: Wikimedia Commons

It is also known that Cort Aslakssøn and Christian Longomontanus acquired lenses and built their own telescopes in the first couple of years of telescopic astronomy in Copenhagen, but unfortunately I haven’t, until now, been able to find any more details of activities in this direction. If any of my readers could direct me to any literature on the subject I would be very grateful.

Christian Severin known as Longomontanus

Turning to Italy we find the astronomers on the Collegio Romano under the watchful eye of Christoph Clavius making telescopic astronomical observations before Galileo published his Sidereus Nuncius in 1610, using a Dutch telescope sent to Odo van Maelcote by one of his earlier students Peter Scholier. Grégoire de Saint-Vincent would later claim that he and Odo van Maelcote were probably the very first astronomers to observe Saturn using a telescope. It was the astronomers of the Collegio Romano, most notably Giovanni Paolo Lembo and Christoph Grienberger, who would then go on to provide the very necessary independent confirmation of the discoveries that Galileo had published in the Sidereus Nuncius.

As can be seen Galileo was anything but the singlehanded pioneer of telescopic astronomy in those early months and years of the discipline. What is interesting is that those working within the discipline were not isolated lone warriors but a linked network, who exchanged letter and publications with each other.

Some of the connections that existed between the early telescopic astronomers are listed here: Harriot had corresponded extensively with Kepler and was very well informed about what Tycho and the other continental astronomers were up to. David Fabricius corresponded with Kepler and Tycho and even visited Tycho in Prague but unfortunately didn’t meet Kepler on his visit. Johannes would later take up correspondence with Kepler. Tycho corresponded with Magini in Bologna who passed on his news to both Galileo and Clavius. Clavius was also very well informed of all that was going on in European astronomy by the Jesuit network. Almost all of the Jesuit astronomers were students of his. Marius corresponded with Kepler, who published many of his astronomical discoveries before he did, and with David Fabricius, whom he had got to know when he visited Tycho in Prague to study astronomy. Longomontanus had earlier been Tycho’s chief assistant and corresponded with Kepler after he left Prague to return to Copenhagen. Interestingly another of Tycho’s assistants, Johannes Eriksen, visited both David Fabricius in Friesland and Thomas Harriot in London on the same journey.

What we have here is not Galileo Galilei as singlehanded pioneer of telescopic astronomy but a loosely knit European community of telescopic astronomers who all recognised and utilised the potential of this new instrument shortly after it appeared. They would soon be joined by others, in this case mostly motivated by Galileo’s Sidereus Nuncius, a few of them even supplied with telescopes out of Galileo’s own workshop. However what is very important to note is that although Galileo was without doubt the best telescopic observer of that first generation and certainly won the publication race, all of the discoveries that he made were also made independently and contemporaneously by others, so nothing would have been lost if he had never taken an interest in the spyglass from Holland.






[1] Because I pointed out the errors contained in this claim in a comment, it has now been removed from the Facebook post!

[2] J. L. Heilbron, Galileo, OUP, 2010, p. 151


Filed under History of Astronomy, History of Optics, History of science, Uncategorized