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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

Measure for measure

The Brexit vote in the UK has produced a bizarre collection of desires of those Leavers eager to escape the poisonous grasp of the Brussels’ bureaucrats. At the top of their list is a return of the death penalty, a piece of errant stupidity that I shall leave largely uncommented here. Not far behind is the wish to abandon the metric system and to return to selling fruit and vegetables in pounds and ounces. This is particularly strange for a number of reasons. Firstly the UK went metric in 1965, six years before it joined the EU. Secondly EU regulations actually allows countries to use other systems of weights and measures parallel to the metric system, so there is nothing in EU law stopping greengrocers selling you a pound of carrots or bananas. Thirdly the country having gone metric in 1965, anybody in the UK under the age of about fifty is going to have a very hard time knowing what exactly pounds and ounces are.

Most readers of this blog will have now gathered that I have spent more than half my life living in Germany. Germany is of course one of the founding states of the EU and as such has been part of it from the very beginning in 1957. The various states that now constitute Germany also went metric at various points in the nineteenth century, the earliest in 1806-15, and the latest in 1868. However the Germans are a very pragmatic folk and I can and do buy my vegetables on the market place in Erlangen in pounds and half pounds. The Germans like most Europeans used variation of the predecessors to the so-called Imperial system of weights and measures and simple re-designated the pound (Pfund in German) to be half a kilo. The Imperial pound is actually approximately 454 grams and for practical purposes when buying potatoes or apples the 46-gram difference if negligible. Apparently the British are either too stupid or too inflexible to adopt such a pragmatic solution.

At the beginning of the month Tory dingbat and wanna be journalist Simon Heffer wrote an article in The Telegraph with the glorious title, Now that we are to be a sovereign nation again, we must bring back imperial units. I haven’t actually read it because one has to register in order to do so and I would rather drink bleach than register with the Torygraph. I shall also not link to the offending article, as it will only encourage them. Heffer charges into the fray thus:

But I know from my postbag that there is another infliction from the decades of our EU membership that many would like to be shot of, and that was the imposition of the metric system on large parts of our life. 

Consumer resistance ensured that our beer is still served in pints (though not in half-pint and pint bottles when bought in supermarkets: brewers please note), and that our signposts are still marked in miles.

As pointed out above it was not the EU who imposed the metric system on British lives but the British government before the UK joined the EU. According to EU regulations you can serve drinks in any quantities you like just as long as the glasses are calibrated, so keeping the traditional pint glasses and mugs in British pubs was never a problem. Alcohol is sold in Germany in a bewildering range of different size glasses depending on the local traditions. My beer drinking German friends (the Germans invented the stuff, you know) particularly like pints of beer because they say that they contain a mouthful more beer that a half litre glass. Sadly many bars in Franconia have gone over to selling beer in 0.4litre glasses to increase their profits, but I digress.

UK signposts are still marked in miles because the government could not afford the cost of replacing all of them when the UK went metric. Expediency not national pride was the motivation here.

Just before Heffer’s diatribe disappears behind the registration wall he spouts the following:

But we have been forced on to the Celsius temperature scale, which is less precise than Fahrenheit

When I read this statement I went back to check if the article had been published on 1 April, it hadn’t! Is the international scientific community aware of the fact that they have been conned into using an inaccurate temperature scale? (I know that scientist actually use the Kelvin temperature scale but it’s the same as the Celsius scale with a different zero point, so I assume by Heffer’s logic(!) it suffers from the same inaccuracy). Will all of those zillions of experiments and research programmes carried out using the Celsius/Kelvin scale have to be repeated with the accurate Fahrenheit scale? Does Simon Heffer actually get paid for writing this crap?


Anders Celcius Portrait by Olof Arenius Source: Wikimedia Commons


Daniel Gabriel Fahrenheit

Like myself on being confronted with the bring back imperial weights and measures madness lots of commentators pointed out that the UK went metric in 1965 but is this true? No, it isn’t! The UK actually went metric, by act of parliament over one hundred years earlier in 1864! The nineteenth century contains some pretty stirring history concerning the struggles between the metric and imperial systems and we will now take a brief look at them.

As soon as it became in someway necessary for humans to measure things in their environment it was fairly obvious that they would use parts of their body to do so. If we want a quick approximate measure of something we still pace it out or measure it with the length of an arm or the span of our fingers. So it was natural that parts of the body became the units of measurement, the foot, the forearm, the arm span and so on and so forth. This system of course suffers from the fact that we are not all the same size. My foot is shorter than yours; my forearm is longer than my partners. This led cultures with a strong central bureaucracy to develop standard feet and forearms. The various Fertile Crescent cultures developed sophisticated weights and measures systems, as did the Roman Empire and it is the latter that is the forefather of the imperial system. The Roman foot was between 29.5 and 30 cm, the pace was 2.5 feet and the Roman mile was 5000 feet. The word mile comes from the Latin for thousand, mille. The Roman military, which was very standardised, carried the Roman system of weights and measures to large parts of Europe thus establishing their standards overall.

With the collapse of the Roman Empire their standardised system of weights and measures slowly degenerated and whilst the names were retained their dimensions varied from district to district and from town to town. In the eighth and ninth centuries Karl der Große (that’s Charlemagne for the Brits) succeeded in uniting a substantial part of Europe under his rule. Although he was uneducated and illiterate he was a strong supporter of education and what passed at the time for science and amongst his reforms he introduced a unified system of weights and measures for his entire empire, another forefather of the imperial system. Things are looking quite grim for the anti-European supporters of the imperial system; it was born in Rome the birthplace of the EU and was reborn at the hands of a German, nothing very British here.

Karl’s attempt to impose a unified system of weights and measures on his empire was not a great success and soon after his death each district and town went back to their own local standards, if they ever left them. Throughout the Middle Ages and deep into the Early Modern Period traders had to live with the fact that a foot in Liège was not the same as a foot in Venice and a pound in Copenhagen was not a pound in Vienna.

This chaos provided work for the reckoning masters producing tables of conversions or actually doing the conversions for the traders, as well as running reckoning schools for the apprentice traders where they taught the arithmetic and algebra necessary to do the conversions, writing the textbooks for the tuition as well. The lack of unity in currency and mensuration in medieval Europe was a major driving force in the development algebra – the rule of three ruled supreme.

At the beginning of the seventeenth century Simon Stevin and Christoph Clavius introduced decimal fractions and the decimal point into European mathematics, necessary requirements for a decimal based metric system of mensuration. Already in the middle of the seventeenth century just such a system emerged and not from the dastardly French but from a true blue English man, who was an Anglican bishop to boot, polymath, science supporter, communicator, founding member of the Royal Society and one of its first secretaries, John Wilkins (1614–1672).

Greenhill, John, c.1649-1676; John Wilkins (1614-1672), Warden (1648-1659)

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

Asked by the society to devise a universal standard of measure he devoted four pages of his monumental An Essay towards a Real Character and a Philosophical Language (1668) to the subject.


Title Page Source: Wikimedia Commons

He proposed a decimal system of measure based on a universal measure derived from nature for use between ‘learned men’ of various nations. He considered atmospheric pressure, the earth’s meridian and the pendulum as his universal measure, rejecting the first as susceptible to variation, the second as immeasurable and settled on the length of the second pendulum as his measure of length. Volume should be the cubic of length and weight a cubic standard of water. To all extents and purposes he proposed the metric system. His proposal fell, however, on deaf ears.


European units of length in the first third of the 19th century Part 1


European units of length in the first third of the 19th century Part 2

As science developed throughout the seventeenth and eighteenth century it became obvious that some sort of universal system of measurement was a necessity and various people in various countries addressed to subject. In 1790 the revolutionary Assemblée in France commissioned the Académie to investigate the topic. A committee consisting of Jean-Charles de Borda, Joseph-Louis Lagrange, Pierre-Simon Laplace, Gaspard Monge and Nicolas de Condorcet, all leading scientific figures, recommended the adoption of a decimal metric system based on one ten-millionth of one quarter of the Earth’s circumference. The proposal was accepted by the Assemblée on 30 March 1791. Actually determining the length of one quarter of the Earth circumference turned into a major project fraught with difficulties, which I can’t do justice to here in an already overlong blog post, but if you are interested then read Ken Adler’s excellent The Measure of All Things: The Seven-Year Odyssey That Transformed The World.


Standard meter on the left of the entrance of the french Ministère de la Justice, Paris, France. Source: Wikimedia Commons

However Britain needed a unified system of mensuration, as they still had the problem that every town had different local standards for foot, pound etc. John Herschel the rising leading scientific figure wanted a new decimal imperial system based on the second pendulum but in the end parliament decide to stick with the old imperial system taking a physical yard housed in the Houses of Parliament as the standard for the whole of the UK. Unfortunately disaster struck. The Houses of Parliament burnt down in 1834 and with it the official standard yard. It took the scientists several years to re-establish the length of the official yard and meanwhile a large number were still advocating for the adoption of the metric system.


The informal public imperial measurement standards erected at the Royal Observatory, Greenwich, London, in the 19th century: 1 British yard, 2 feet, 1 foot, 6 inches, and 3 inches. The inexact monument was designed to permit rods of the correct measure to fit snugly into its pins at an ambient temperature of 62 °F (16.66 °C) Source: Wikimedia Commons

The debate now took a scurrile turn with the introduction of pyramidology! An English writer, John Taylor, developed the thesis that the Great Pyramid was constructed using the imperial system and that the imperial system was somehow divine. Strangely his ideas were adopted and championed by Charles Piazzi Smyth the Astronomer Royal of Scotland and even received tacit and indirect support from John Herschel, who rejected the pyramidology aspect but saw Taylor’s pyramid inch as the natural standard of length.

However wiser heads prevailed and the leaders of the British Victorian scientific community made major contributions to the expansion of the metric system towards the SI system, used internationally by scientists today. They applied political pressure and in 1864 the politicians capitulated and parliament passed the Metric (Weights and Measures) Act. This permitted the use of weights and measures in Britain. Further acts followed in 1867, 1868, 1871 and 1873 extending the permitted use of the metre. However the metric system could be used for scientific purposes but not for business. For that, Britain would have to wait another one hundred and one years!

Interestingly, parallel to the discussion about systems of mensuration in the nineteenth century, a discussing took place about the adoption of a single prime meridian for cartographical, navigational, and time purposes. In the end the two main contenders were the observatories in Paris and Greenwich. Naturally neither Britain nor France was prepared to concede to the other. To try and solve the stalemate it was suggested that in exchange for Paris accepting Greenwich as the prime meridian London should adopt the metric system of measurement. By the end of the nineteenth century both countries had nominally agreed to the deal without a formal commitment. Although France fulfilled their half of this deal sometime early in the twentieth century, Britain took until 1965 before they fulfilled their half.

Should the Leavers get their wish and the UK returns to the imperial system of measurement then they will be joining an elite group consisting of the USA, Myanmar and Liberia, the only countries in the world that don’t have the metric system as their national system of measurement for all purposes.


Filed under History of Mathematics, History of Navigation, History of science, Uncategorized

A birthday amongst the stars

Readers will probably be aware that as well as writing this blog I also hold, on a more or less regular basis, semi-popular, public lectures on the history of science. These lectures are as diverse as this blog and have been held in a wide variety of places. However I have, over the years, held more lectures in the Nürnberg Planetarium than anywhere else and last Thursday I was once again under the dome, this time not to hold a lecture but to help celebrate the ninetieth birthday of this august institution.

Before the twentieth century the term planetarium was a synonym for orrery, a mechanical model, which demonstrates the movements of the planets in the solar system. The beginnings of the planetarium in the modern sense was as Walther Bauersfeld, an engineer of the German optics company Zeiss, produced the plans for the construction of a planetarium projector based on earlier concepts. In 1923 the world’s first planetarium projector, the Zeiss Mark I, was demonstrated in the Zeiss factory in Jena and two months later on 21 October in the Deutschen Museum in Munich. Following further developments the first planetarium was opened in the Deutschen Museum on 7 May 1925.

Zeiss Mark I Planetarium Projector

Various German town and cities followed suit and the city council of Nürnberg signed a contract with Zeiss for a planetarium projector on 12 February 1925. The contract called for the city council to pay Zeiss 150, 000 Reichsmark ( a small fortune) in three instalments and 10% of the takings from the public shows. In a building on Rathenauplatz designed by Otto Ernst Schweizer the Nürnberg planetarium opened ninety years ago on 10 April 1927.

Original Nürnberg Planetarium

Fitted out with a new Zeiss Mark II projector the first of the so-called dumbbell design projectors with a sphere at each end for the north and south hemispheres. It was the world’s ninth planetarium.

Zeiss Mark II Planetarium Projector

From the very beginning the planetarium was born under a bad sign as the NSDAP (Nazi) city councillor, Julius Streicher, (notorious as the editor of the anti-Semitic weekly newspaper Der Stürmer) vehemently opposed the plans of the SPD council to build the planetarium. On 30 January 1933 the NSDAP seized power in Germany and the days of the planetarium were numbered. In November the planetarium director was ‘persuaded’ to recommend closing the planetarium and at the beginning of December it was closed. There were discussions about using the building for another purpose but Streicher, now Gauleiter (district commissioner) of Franconia was out for revenge. In March 1934 the planetarium was demolished on Streicher’s orders, with the argument that it looked too much like a synagogue! However the projector, and all the technical equipment, was rescued and put into storage.

Historischer Kunstbunker Entrance: There are guided tours

During the Second World War the projector was stored together with the art treasures of the city in the Historischer Kunstbunker (historical art bunker), a tunnel under the Castle of Nürnberg.

Following the war, in the 1950s, as Nürnberg was being rebuilt the city council decided to rebuild the planetarium and on 11 December 1961 it was reopened on the new site on the Plärrer, with an updated Zeiss Mark III. During the celebrations for the five hundredth anniversary of the death of Nicolaus Copernicus in 1973, whose De revolutionibus was printed and published in Nürnberg, the planetarium became the Nicolaus-Copernicus-Planetarium. In 1977 the Mark III projector was replaced with a Mark V, which is still in service and in 2010 the planetarium entered the twenty-first century with a digital Full-Dome projector.

Nicolaus-Copernicus-Planetarium am Plärrer in Nürnberg (2013)

The Zeiss Mark V Planetarium Projector in Nürnberg

Since the 1990’s the planetarium has been part of the City of Nürnberg’s adult education complex and alongside the planetarium programme it is used extensively for STEM lectures. I shall be holding my next lecture there on 28 November this year about Vannevar Bush, Claude Shannon, Robert H Goddard and William Shockley- Four Americans Who Shaped the Future (in German!) and if you’re in the area you’re welcome to come and throw peanuts.





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

Happy Birthday Conrad – #GesnerDay 2017

This is a rolling post collating all the contribution made today to celebrate the 501st birthday of the Swiss polymath Conrad Gesner.

Conrad’s birthday has ended and with it this rolling blog closes. We thank all of those who contributed to #GesnerDay 2017 and made it a great birthday party for Switzerland’s best loved polymath. We hope you will all be back at the same time next year for #GesnerDay 2018.


Conrad Gesner based on a painting by Tobias Stimmer (1539–1584)


Celebrating Gesner at the Smithsonian: Behind the scenes tour video

The Guardian: 16th century ‘zoological goldmine’ discovered – in pictures


Spiky blowfish Gessner had this image drawn in Frankfurt from a dried blowfish. Such dried fish decorated the shops of many European apothecaries at the time. Gessner used this drawing as the model for a printed full-page illustration in the fish volume (1558) of his Historia Animalium, but he made a subtle change. While a hook (from which the fish can be hung) pulls up the dried skin into a bump, that hook disappeared in the printed illustration. In this way he turned a portrait of an individual dried fish into a scientific representation of a fish species. Photograph: Special Collections of the University of Amsterdam

The Renaissance Mathematicus: Putting the lead in your pencil


The first ever published illustration of a pencil from Conrad Gesner’s De rerum fossilium


Dracones (from Gesner’s 1587 »Historiae Animalium Liber V, qui est de Serpentium natura«) h/t Patrick J Burns


Shark teeth depicted in C. Gesner´s “De Rerum fossilium…[]”. Such figures made it possible for other naturalists to compare their fossils with specimens of other collectors or hosted in private, non easily accessible, collections. However the quality of the used wood cuts was still poor and were soon replaced by copper engravings, with a higher reproduction quality.

The Renaissance Mathematicus: Friends

Fraumünster and the Münster close on the altarpiece of Hans Leu the Older (1460-1507) Where Conrad Gesner and Georg Joachim Rheticus went to school and became friends Source: Wikimedia Commons

University of Glasgow Library: Conrad Gesner: Illustrated Inventories with the use of Wonderful Woodcuts

Conrad Gesner ‘Tiger’ (Sp Coll Hunterian A.a.1.2)

Hyper allergic: The 16th-Century Fossil Book that First Depicted the Pencil


Frontispiece image from Conrad Gessner’s ‘De Rerum Fossilium Lapidum et Gemmarum Maxime, Figuris et Similitudinibus Liber’ (1565)

Jeff Ollerton’s Biodiversity Blog: Celebrating Conrad Gesner Day 2017

Gessner House Zürich
Photo: Jeff Ollerton 2008





Today is Conrad Gesner’s 501st birthday! Explore his publications in Biodiversity Heritage Library




Gesner’s (born 1516) “Historia Animalium”  is full of monsters. Why? Monsters Are Real


Scorpions (Order Scorpiones). Conrad Gesner, Historia Animalium, Liber 2 (1586) in @BioDivLibrary: h/t Historical SciArt  

NYAM Blog: Happy Bird-day, Conrad Gesner


SciHi Blog: Conrad Gessner’s Truly Renaissance Knowledge


The Pachyderm, from Conrad Gesner ‘Historiae animalium‘ (1551-58)



Happy B-day, Conrad Gesner! G’s #marginalia re bison in his copy of Icones 1560 #GesnerDay #histSTM @ZBZuerich h/t Michal Choptiany   


Peacock (Genus Pavo). Conrad Gesner, Historia Animalium, Liber 3 (1585) in @BioDivLibrary: h/t Historial SciArt


Gurnard (Dactylopterus volitans?). Conrad Gesner, Historia Animalium, Liber 2 (1586) in @BioDivLibrary h/t Historical SciArt   

Renaissance Quarterly: Ann Blair: The 2016 Josephine Waters Bennett Lecture: Humanism and Printing in the Work of Conrad Gessner


Anglerfish (Order Lophiiformes). Conrad Gesner, Historia Animalium, Liber 2 (1586) in @BioDivLibrary: h/t Historical SciArt  


Sea Monsters for #GesnerDay! Conrad Gesner, Historia Animalium, Liber 2 (1586) in @BioDivLibrary: h/t Historical SciArt  


The naturalist’s library. Conducted by Sir William Jardine: MEMOIR OF GESNER h/t William Ulate  


h/t William Ulate   


Until next year, #GesnerDay! Here’s your #MondayMotivationOwl! Explore more of Gesner’s works in @BioDivLibrary: h/t Historical SciArt





Filed under Uncategorized