Tag: science

Apr 23 2011

The naming of things

This post is a response to one of the points Rebekah Higgit makes over at “Whewell’s Ghost” on “Dos and Don’ts of history of science”. It’s all about scientists:

1) Do not ever call anyone a scientist who would not have recognised the term. The word was not coined until the 1830s (by William Whewell himself) but a) he meant something rather different by it and b) the word was not actually used until the 1870s. If we use the term to describe anyone before this date we risk loading their views, status, career, ambitions and work with associations that just do not exist before this date.I may know what I mean if it slips out in my description of an 18th-century astronomy, but the person listening to me will hear all sorts of other things. It too easily glides over points such as the fact that individuals probably did something else to make their living, or were personally wealthy. Science was not a career, or a vocation. I could give many further examples, and expand this rule into to using actors’ categories elsewhere, but this is the fundamental point. Not only did the word not, essentially, exist pre-1870 but there was no equivalent and no such idea. Awkward as it can sometimes be, man of science, natural philosopher, mathematician, astronomer, physician, naturalist or whatever should always be used instead.

I disagree with this. I should point out that I don’t consider this a Marmite* argument: the point Rebekah makes is not unreasonable and arguing serves to reinforce the point she is making. That the lives of “scientists” in the past were very different from the lives of most modern “scientists” is an entirely fair point, and is perhaps what the history of science is all about.

Since Rebekah is a professional historian of science, I feel my best approach is to argue this point on linguistic and scientific grounds, since I am a scientist not a historian. The OED says a scientist is:

  1. A person with expert knowledge of a science; a person using scientific methods.

it goes on to describe its coining via almost joking discussions over the British Association for the Advancement of Science in 1834 to Whewell’s use in 1840.

Precluding the use of the word “scientist” from application to people living before it was introduced seems to rather limit our options – how far must this sanitisation of language extend? Our use of words evolves in time. There are parallels here with Maxwell’s equations: in the mathematical language of his time his equations were clumsy and verbose, in more modern notation they are much more compact (and to overuse a word “elegant”). Working scientists don’t use Maxwell’s original notation, they use the modern notation because it captures the essential elements of the original work but is easier to use.

In my view the heart of the issue is the way in which we define scientists, to me being a scientist is defined operationally: by what I do in applying the scientific method, and by inference what people did in the past. Rather than socially or economically: what I have been trained to do or what people would pay me to do. I would still be a scientist if I were not paid for it, and hadn’t been trained. In both cases I might be poorer, but in different senses of the word!

There is also a point about communication here too: using a word for which you and your colleagues hold a specialist, narrow meaning may be “correct” but not help with communication. Knowing that your definition and the definition your audience hold is different is important but does not mean you should hold your definition sacrosanct – I face the same issue communicating my specialist area of science.

Perhaps the issue here is that Rebekah takes scientist to mean “modern professional scientist” whilst my definition is more catholic.

This does lead to the question: should I describe myself as a historian?

*Appropriate here since I work for the company that makes Marmite.

Apr 09 2011

Book Review: The Chemist Who Lost His Head by Vivian Grey

Portrait_of_Antoine-Laurent_Lavoisier_and_his_wife

Following on from “The Measure of All Things” my interest in Antoine Lavoisier was roused, so I went off to get a biography: “The Chemist who lost his head: The Story of Antoine Laurent Lavoisier” by Vivian Grey. This turns out to be a slim volume for the younger reader, in fact my copy appears to arrive via the Jenks East Middle School in Tulsa. As a consequence I’ve read it’s 100 or so pages in under 24 hours – that said it seems to me a fine introduction.

Antoine Lavoisier lived 1743-1794. He came from a bourgeoisie family, the son of a lawyer, and originally training as a lawyer. Subsequently he took up an education in a range of sciences. As a young man, in 1768, he bought into the Ferme Générale which was to provide him with a good income but led to his demise during the French Revolution. The Ferme Générale was the system by which the French government collected tax, essentially outsourcing the process to a private company. Taxes were collected from the so-called “Third Estate”, those who were not landed gentry or clergy. Grey indicates that Lavoisier was a benign influence at the Ferme Generale, introducing a system of pensions for farmers and doing research into improved farming methods. Through the company he met his future wife, Marie Anne Pierrette Paulz, daughter to the director of the Ferme – Antoine and Marie married in 1771 when she was 14 and he 28.

Lavoisier started his scientific career with a geological survey of France, which he conducted as an assistant to Jean Etienne Guettard between 1763 and 1767. This work was to be terminated by the King, but was completed by Guettard with Antoine Grimoald Monnet although Lavoisier was not credited. There seems to be some parallel here with William Smith’s geological map of the UK produced in 1815.

Through his geological activities Lavoisier became familiar with the mineral gypsum, found in abundance around Paris. He undertook a detailed study of gypsum which sets the theme for his future chemical research: making careful measurements of the weight of material before and after heating or exposure to water. He discovered that gypsum is hydrated: when heated it gives off water, when the dehydrated powder (now called plaster of Paris) is re-hydrated it forms a hard plaster. He wrote this work up and presented it to the Académie des Sciences – the French equivalent of the Royal Society, on which I have written repeatedly.

He was to present several papers to the Académie before being elected a member of this very elite group at the age of twenty-five, half the age of the next youngest member. Once a member he contributed to many committees advising on things such as street lighting, fire hydrants and other areas of civic interest, the Académie was directly funded by the King and more explicitly tasked with advising the government than the Royal Society was. Lavoisier was also involved in the foundation of the new metric system of measurement, which was the subject of “The Measure of All Things”. Lavoisier became one of four commissioners of gunpowder – an important role at the time. During his life he would have had contact with Joseph Banks – a long term president of the Royal Society, and also Benjamin Franklin – scientist and also United States Ambassador to France.

From a purely scientific point of view Lavoisier is best known for his work in chemistry: his approach of stoichiometry – the precise measurement of the mass of reactants in chemical reactions led to his theory of combustion which ultimately replaced the phlogiston theory. It is this replacement of phlogiston theory with the idea of oxidization that forms the foundation of Kuhn’s “paradigm shift” idea, so Lavoisier has a lot to answer for!

The portrait of Antoine and Marie Laviosier at the top of the page is by Jacques-Louis David painted ca. 1788. It strikes me as quite an intimate portrait with Marie pressed against Antoine, looking directly at the viewer whilst her husband looks at her. Marie played a significant part in the work of Lavoisier, as well as recording experiments and drawing apparatus (something that takes good understanding to do well), and assisting with correspondence and translation  she was also responsible for publishing Mémoires de Chimie after his death. She was a skilled scientist in her own right. The equipment on the table and floor can be identified: on the floor is a portable hydrometer and a glass vessel for weighing gases. On the table are a mercury gasometer, and a glass vessel container mercury – likely illustrating the properties of oxygen and nitrogen in air.

Antoine Lavoisier was executed in 1794, for his part in the Ferme Générale. His execution is attributed, at least in part to the ire of Jean-Paul Marat, who Lavoisier had earlier blocked from membership of the Académie des Sciences. It seems Lavoisier had been warned by friends that his life was in danger but appeared to think his membership of the Académie des Sciences would protect him. Ironically Jacques-Louis David also painted “The Death of Marat”.

100 pages on Lavoisier was not enough for me, I’m going for “Lavoisier” by Jean-Pierre Poirier next – some fraction of which appears to be available online, but I’m going for a paper copy.

Mar 31 2011

Book review: The Measure of All Things by Ken Alder

TheMeasureOfAllThings“The Measure of All Things“ by Ken Alder tells the story of Pierre Méchain and Jean Baptiste Joseph Delambre’s efforts to survey the line of constant longitude (or meridian) between Dunkerque and Barcelona through Paris, starting amidst the French Revolution in 1792.

The survey of the meridian was part of a scheme to introduce a new, unified system of measures. The idea was to fix the length of the new unit, the metre, as 1/10,000,000th of the distance between the North Pole and the equator on a meridian passing through Paris.

At the time France used an estimated 250,000 different measures across the country with each parish having it’s own (uncalibrated) weights and measures with different measures for different types of material i.e. a “yard” of cotton was different from a “yard” of silk, and different if you were buying wholesale or selling to end users. These measures had evolved over time to suit local needs, but acted to supress trade between communities. Most nations found themselves in a similar situation.

Although the process of measuring the meridian started under the ancien regime, it continued in revolutionary France as a scheme that united the country. The names associated with the scheme: Laplace, Legrendre, Lavoisier, Cassini, Condorcet, leading lights of the Academie des Sciences, are still well known to scientists today.

Such surveying measurements are made by triangulation, a strip of triangles is surveyed along the line of interest. This involves precisely measuring the angles between each each vertex of the triangles in succession: given the three angles of a triangle and the length of one side of the triangle the lengths of the other two sides can be calculated. It’s actually only necessary to measure the length of one side on one triangle on the ground. Once you’ve done that you can use the previously determined lengths for successive triangles. All of France had been surveyed under the direction of César-François Cassini in 1740-80, the meridian survey used a subset of these sites measured at higher precision thanks to the newly invented Borda repeating circle. As well as this triangulation survey a measure of latitude was made at points along the meridian by examining the stars.
The book captures well the feeling of experimental measurement: the obsession with getting things to match up via different routes; the sick feeling when you realise you’ve made a mistake perhaps never to be reversed; the frustration at staring at pages of scribbles trying to find the mistake; the pleasure in things adding up.

Méchain and Delambre split up to measure the meridian in two sections: Delambre taking the northern section from Dunkerque to Rodez and Méchain the section from Rodez to Barcelona. Méchain delayed endlessly throughout the project, trusting little measurement to his accompanying team. Early on in the process, at Barcelona, he believed he had made a terrible error in measurement, but was unable to check whilst Spain and France were at war. He was wracked by doubt for the following years, only handing over doctored notes with great reluctance at the very end of the project. He was to die not long after the initial measurements were completed, leaving his original notes for Delambre to sift through.

At the time the measurements were originally made the understanding of experimental uncertainty, precision and accuracy were poorly developed. Driven in part by the meridian project and similar survey work by Gauss in Germany, statistical methods for handling experimental error more rigorously were developed not long afterwards. I wrote a little about this back here. Satellite surveying methods show that the error in the measurement by Méchain and Delambre is equivalent to 0.2 millimetres in a metre or 0.02%.

In the end the Earth turns out not to be a great object on which to base a measurement system: although it’s pretty uniform it isn’t really uniform and this limits the accuracy of your units. The alternative proposed at the time was to base the metre on a pendulum: it was to have the length necessary to produce a pendulum of period 2 seconds. This is also ultimately based on properties of the Earth since the second was defined as a certain fraction of the day (the time the Earth takes to rotate on its axis) and the local gravity which varies slightly from place to place, as Maskelyne demonstrated.

Following the Revolution, France adopted, for a short time, a decimal system of time as well as metric units but these soon lapsed. However, the new metric units were taken up across the world over the following years – often this was during unification following war and upheaval.

The definition of the basic units used in science is still an active area. The definition of the metre has not relied on a unique physical object since 1960, rather it is defined by a process: the distance light travels in a small moment of time. However, the kilogram is still defined by a physical object but this may end soon with some exquisitely crafted silicon spheres.

I must admit to being a bit wary of this book in the first instance, how interesting can it be to measure the length of a line? However, it turns out I like to read history through the medium of science and the book provides an insight into France at the Revolution. Furthermore measuring the length of a line is interesting, or it is to a physicist like me.

Thanks to @beckyfh for recommending it!

Footnotes
1. The full-text of the three volume “Base du système métrique décimal” written by Delambre is available online. The back of the second volume contains summary tables of all the triangles and a diagram showing their locations.
2. The author’s website.
3. Some locations in Google Maps.

Mar 08 2011

Book review: Doomsday Men by P.D. Smith

DoomsdayMenMy next book review is on Doomsday Men: The Real Dr Strangelove and the Dream of the Superweapon by P.D. Smith. I arrived at this book via the comments on my earlier post about the Manhattan Project, the Allied project to develop the atomic bombs dropped on Hiroshima and Nagasaki at the end of the Second World War. I also wrote about science fiction, which is relevant to this book too.

Doomsday Men brings context to the Manhattan Project, it shows the early imagining of what radioactivity could bring in terms of weapons of war, it shows science fiction writers foreseeing the applications, politicians considering the practical use of weapons of mass destruction and scientists working towards them. Alongside atomic weapons the potential for war from the air had been well considered before it was implemented.

The book starts with the conception of a genuine doomsday superweapon, that’s to say one that would wipe out all life on earth. This had been a theme of science fiction in the past, but in the early 1950’s it became plausible. Essentially the trick is to set off a fusion explosion in the presence of a large quantity of a particular element, cobalt, which would pick up neutrons becoming intensely radioactive whilst being vapourised and cast up into the atmosphere to settle the world over providing a lethal dose of radiation. The amount of cobalt required is about 10,000 tonnes which is only a cube with sides 10 metres long. There’s an open question as to whether the dust would be distributed uniformly enough to wipe out all life.

Leo Szilard is a central character through the book, along with fellow Hungarians John Von Neumann, Eugene Wigner and Edward Teller, known collectively as the Hungarian Quartet. They arrived in the US, fleeing anti-Semitism in Europe and were to play an important part in the development of nuclear weapons. It’s very striking the number of European Jews who migrated to the US in the period after the First World War, including Albert Einstein and Enrico Fermi. In the first instance many of them were keen to help in the development of nuclear weapons as a response to Hitler’s rise in Germany: a state they believed had both the technical ability to make such weapons and, with Hitler, the will to use them in war. Towards the end of the Second World War many of them felt less enthusiastic about their use against the Japanese, despite Japan’s hideous development and use of biological weapons against the Chinese in the 1930’s. Following the war, Von Neumann and particularly Teller continued to be involved in further developments now driven by anti-Communism sentiments.

The route to the doomsday weapon started with the discovery of radioactivity towards the end of the 19th century, and in particular the discovery of radium by Pierre and Marie Curie at the turn of the century. Around 1902 Frederick Soddy and Sir William Crookes both highlighted the huge amounts of energy was bound up in matter. Crookes saying: “one gram could raise the entire fleet of the British Navy several thousand fleet in the sky”. By 1913 H.G. Wells had very explicitly written about a nuclear weapon in “A World Set Free”. The use of chemical weapons, tanks and aeroplanes in war had all been imagined well before they were used too. Clearly there are big technical issues to address in going from a science fiction idea to a real system in battle, but the point here is that these ideas had serious public currency well before they were realised: there could be no “we’ll keep this quiet and no-one will think of it”. In a sense the key theme of the book is the interweaving of fiction with fact through the first half of the 20th century.

It was during the First World War that “scientific” superweapons started to be used, and the importance of science in waging war started to be recognised explicitly. Fritz Haber, a chemist, Nobel prize-winner for his commercial synthesis of ammonia, contemporary of Einstein, was instrumental in bringing chemical weapons to war, he was a German nationalist and felt the development of such weapons a duty to his country. He seemed quite enthusiastic about his work, writing:

“Chlorine: easy to liquefy, disastrous to the human organism, very cheap, mind you! Phosgene: ten times as strong as chlorine. Mustard gas: the best fighting gas of all”.

Once the Germans had used chemical weapons the British and French quickly developed their own. Research and manufacture of chemical weapons was to involve up to 75,000 people by the end of the war – this is about half the number involved in the Manhattan Project. A minority of scientists considered chemical warfare as a blessing compared to the conventional equivalent, for many others it was utterly abhorrent. The military had mixed feelings. Chemical weapons were banned by a variety of treaties, practically they seemed something of a double-edged sword with the first British use of chlorine at Loos causing 2000 casualties on their own side which perhaps explains why they’ve been so rarely used since. With the rise of Nazism Haber, a Jew, was to flee Germany and die shortly thereafter.

The First World War also saw the foundation of the British Board of Invention and Research in 1916, tasked with finding science to fight wars – it sought ideas from the public, one of the which was to train cormorants to peck out the mortar between bricks!

Biological weapons were to be developed by the Japanese whilst at war in China during the 1930’s and the Second World War, in an effort led by Shiro Ishii. During this period thousands were to die through his work, many in a range of human experiments to match those carried out by the Nazi doctors. Following the Second World War Ishii was given immunity from prosecution in order that the US could obtain information on biological weapons from him.

So chemistry and biology produced rather unpleasant weapons but they could not be described as decisive: for that you need physicists.

Szilard was first to realise (in 1933) that an atomic bomb might be made via a chain reaction: the fission of an atomic nucleus producing two or more neutrons which would drive further fission. He made some effort to keep the idea secret, at least from the Germans, via a patent held by the British Admirality. This was a very unusual move for a scientist in an area of pure science. In 1939 he was to visit Roosevelt with Einstein to warn him of the potential for an atomic bomb and the possibility that the Germans would make one. Ultimately this contact led to the Manhattan Project and the bombs dropped on Hiroshima and Nagasaki: killing at least 200,000 people.

One of the recurring themes in fiction was the idea of a scientist discovering the doomsday weapon and then holding the world to ransom for peace with the new “system of the world”: a world government led by scientists and technocrats. This sort of idea is better described as left-wing rather than right-wing. And I can say, as a scientist, that it has a certain appeal! Perhaps this explains something of why scientists are more often perceived as left-wing rather than right-wing.

Doomsday Men ends with the story of Stanley Kubrick’s 1964 film “Dr Strangelove: or How I stopped worrying and learned to love the Bomb”. The title character appears to have been based on a combination of Teller, von Neumann and perhaps Werner von Braun – the German rocket scientist captured by the Americans who went on to found the US space programme.

Overall a rather good read: providing good context to the Manhattan Project and the Cold War, and the importance of science fiction in seeing into the future.

Footnote: one of the drawbacks of reading on a Kindle: I reached the end rather unexpectedly since the footnotes, bibliography, and index take up a third of the book!

Feb 14 2011

Book Review: For all the tea in China by Sarah Rose

ForAllTeaChinaBookI’ve been on a bit of a reading spree: next up is “For all the tea in China” by Sarah Rose. This is the story of Robert Fortune and his trips to China in the mid-nineteenth century to obtain tea plants and the secret of tea manufacture for the East India Company to use in India.

Robert Fortune (1812-1880) was a botanist with a modest background. Starting his working life at the Royal Botanic Garden Edinburgh, he later became Curator of the Chelsea Physic Garden. These were relatively poorly paid posts, however there were few such positions to support a professional botanist without their own means of support. He made several substantial visits to the Far East, funded by the Horticultural Society of London and the British East India Company. He died a wealthy man in large part through the wide range of plant introductions he had made, as well as through sales of artefacts he had acquired in the Far East. The list of introductions is well worth a skim through for the modern gardener:

The East India Company had been given a monopoly of trade to the Far East in 1600, through this monopoly they had built a lucrative trade in silk and tea from China, as well as effectively running India. The trades from China were matched with trades into China of opium from India, by the middle of the 19th century addiction to opium was a significant problem in China. The volume of trade it brought made the East India Company a very significant contributor to British government income (of order 10%). Although there are now many global corporations, the East India Company was one of the first and in many ways most powerful. The company was ultimately to lose its dominance following the Indian Mutiny in 1858, and was finally wound up in 1874. The mutiny was likely the cumulation of a long process since the monopoly that the East India Company enjoyed was not popular with free-marketeers who were starting to come to the fore.

At the time of Fortune’s first trip to China in 1845 the English had long been drinking tea imported from China, in exchange for opium grown in India. The English drank both green and black teas, although unlike the Chinese they added milk and sugar (obtained from another British colonial outpost). The Chinese were keen to keep the secret of both the tea plant, and its manufacture into tea leaves for making tea. Whilst the British, in particular the East India Company were keen to get these secrets believing (correctly) that tea would grow well in Himalayan India and would make a good profit. Some tea was already being grown in the Assam district of India but is was derived from inferior Chinese plants. The tea plant is Camellia sinensis a close relative of the decorative camellias of which Fortune also introduced some species.

Before Fortune’s first visit to China it had not even been established that black tea and green tea came from the same plant, but were processed differently. His trips required considerable subterfuge: Westerners had only recently been allowed into anywhere other than a limited number of ports in China, as a result of the first Opium War and Fortune’s activities went considerably beyond what was allowed even under these revised regulations. One of Fortune’s discoveries was that green tea had been coloured by the Chinese for the export market using Prussian Blue (which is toxic) and gypsum. Following a couple of false starts he was eventually able to transport a large number of highest quality tea plant seedlings to Darjeeling in India, as well as providing skilled tea makers and extensive notes on the tea making process.

The key to Fortune’s success in shipping out tea plants from China were Wardian cases, these are essentially sealed glass environments containing soil and some water. Plants, or more importantly, troublesome seeds could be sealed into these containers and as long as they remained sealed, and given some light there would be a good chance of their biological cargo surviving a lengthy sea journey through a range of climates. Prior to this discovery long distance transplantations were tricky. Nowadays we see Kew Gardens as largely a place of leisure, but in the 19th century it was very much at the heart of the Empire in terms of facilitating the movement of plants around the world for commercial reasons. This type of activity was also an early interest of the Royal Society.

It’s difficult not to draw parallels between the state sanctioned opium trade which the United Kingdom used to support, and its current attitude to drug smuggling. Nor between the industrial espionage of the East India Company in the 19th century, and the current issues with the Chinese approach to intellectual property.

I found the sections of the book reporting Fortune’s travels a bit unfulfilling: they seemed to be a sequence of travel anecdotes involving the mischief caused by his Chinese servants – this style does affect other parts of the books. However, more generally the book made me curious to know more about the East India Company, the Opium Wars and so forth and I felt I’d learnt something about the introduction of tea to India.

I’m tempted by Fortune’s book: Three years’ wanderings in the Northern Provinces of China