Tag: Academie des Sciences

Book Review: Huygens–The Man Behind the Principle by C.D. Andriesse

huygens-man-behind-principle-c-d-andriesseThis post is a review of C.D. Andriesse’s biography “Huygens: The Man Behind the Principle”. Huygens Principle concerns the propagation of light but he carried out a wide range of research, including work on clocks, Saturn (discovering its moon “Titan” and hypothesizing the existence of its rings), buoyancy, circular motion, collisions, musical scales and pendulums. Huygens has made passing appearances in my blog posts on the French Académie des Sciences, on telescopes and also on clocks.

On the face of it is surprising that he is not better known, looking around for biographies of him one finds a rather short list. Andriesse puts this down to much of the personal documentation being in Dutch. The scientist in me feels there should be some quantitative way of measuring how “well known” a historical figure is now, and how “important” they were – I suspect this is an impossible programme. On completing the book I suspect a couple of factors play a part here: Huygens represents something of a transitional figure between the work of Galileo/Descartes, and Newton/Leibniz. Similarly his practical work on clocks and telescopes was impressive for its time but superseded not long thereafter. What we do now in physics owes much more to Newton than to Galileo, furthermore Newton although not prolific published more promptly than Huygens and was President of the Royal Society for 20 or so years before his death in post, whilst Huygens left L’Académie des Sciences sometime before his death in not particularly auspicious circumstances. It isn’t entirely clear whilst reading the book, but it becomes obvious that frequently Huygens’ work was done over long periods and only published quite a long time after it was started, often posthumously.

Huygens was born in the Hague in 1629 and died 1695. Christiaan Huygens’ father, Constantijn was a senior Dutch diplomat and a regular correspondent with René Descartes. Constantijn also met Francis Bacon (and was clearly impressed by him), Bacon and Descartes were important in shaping the development of science in the early 17th century. Bacon in particular set the scene for the way of doing science both in the Royal Society and  L’Académie des Sciences. Constantijn set his son off on a regime of study in the classics, with a view to him becoming a lawyer and following in his footsteps as a diplomat. Sometime around 1643, when Christiaan was 14 years old he started to show promise in mathematics.

Huygens senior provided introductions to Marin Mersenne who introduced him to those circles who became the Académie des Sciences in France. Christiaan Huygens was a paid director of science at L’Académie from its foundation in 1666 until he was excluded from it shortly after the death of Jean-Baptiste Colbert, founder of the organisation and his principle patron, in 1683. The exclusion arose from a combination of the loss of this patron, religious differences, absence due to illness, personal vendettas, opposition to membership of any foreigner and his demand for higher remuneration. Aside from this period at L’Académie, Huygens appears to have lived on the wealth and position of his father.

There’s no doubt that he made significant contributions in the area of mechanics, going beyond what Galileo and Descartes had done but his work was superseded almost immediately by that of Newton, and Leibniz, particularly in the methods of calculus which they developed. Calculus is a tool which makes much of the complex geometrical work that Huygens did obsolete. Leibniz was an informal pupil of Huygens, and they kept up a lengthy correspondence. He also had some exposure to Isaac Newton via the Royal Society.

Andriesse claims that Huygens wrote the first physics formula, relating to collisions. I think we should probably take this with a pinch of salt, but looking at the work he did do on circular motion, collisions, buoyancy, the motion of the pendulum and the shape of a catenary as well as his work on optics it is all very familiar to those that studied physics (at least to the age of 18).

Alongside his mathematical and theoretical physics work, Huygens also made contributions to the development of both clocks and telescopes. He introduced the pendulum clock, and a design of his was tested for determining the longitude by the Dutch East India Company. In practical terms this was not successful but it was a valiant first try. He also made lenses and constructed his own telescopes, here he appears to have been a competent technician and an able theoretician but not reaching the level of Newton, who constructed his own reflecting telescope – the first practical example of its type which was not exceeded for some 30 years or so.

This is a detailed biography of Huygens, drawing heavily on his personal correspondence and covering his scientific achievements in some depth, in the manner of Abraham Pais biography of Einstein. Although the book is pretty readable, the style is odd in places – Huygens is referred to frequently as “”Titan” without any real explanation as to why – it may be that in the original Dutch version, entitled “Titan kan niet slapen” (“Titan can not sleep”) this is a bit more obvious. The author also throws in the odd “Iris” when referring obliquely to sex (at least I think that’s what he’s doing!). Occasionally bits of information are scattered through the text, so we learn when Huygens is born and only 10 pages later do we learn where. There is no strong distinction of when Huygens started working on a publication and when it was actually published.

Perhaps more seriously Andriesse makes an attempt at Freudian analysis of some of Huygens illness, I’m no expert in this but I suspect this approach would be considered out-dated these days. It is also here that the translation perhaps wobbles a bit, with Huygens described as having “symptoms of the hypochondriac” which I think may be a mistranslation of melancholia hypochondriaca which I believe refers more generally to mental illness than the specific modern “hypochondria”.

This said, Andriesse’s biography of Huygens is well worth reading. Christiaan Huygens himself is an interesting subject who made important scientific discoveries across a range of areas.


My Evernotes for the book are here.

Book review: Measure of the Earth by Larrie D. Ferreiro

Measure-of-the-EarthThis post is a review and summary of Larrie D. Ferreiro’s book “Measure of the Earth” which describes the French Geodesic Mission to South America to measure the length of a degree of latitude at the equator. The action takes place in the 2nd quarter of the 18th century, the Mission left France in 1735 with the first of its members returning to Europe in 1744.

The book fits together with The Measure of All Things by Ken Alder, which is about the later French effort to measure a meridian through Paris at the turn of the Revolution in order to define the metre, The Great Arc by John Keay on the survey of India and Map of a Nation by Rachel Hewitt on the triangulation survey of the United Kingdom.

The significance of the measurement was that earlier triangulation surveys of France had indicated that the earth was not spherical, as had pendulum measurements made by Jean Richer in Guyana in 1671 which showed a pendulum there ran 2:28 slower there than in Paris. A Newtonian faction believed that the earth was flattened at the poles, its rotation having led to a bulging at the equator. A Cartesian school held that the earth was flattened around the equator and bulged at the poles, this was not a direct result of work by Rene Descartes but seems to have been more a result of scientific nationalism. Spoiler: the earth is flattened at the poles.

From a practical point of view a non-spherical earth has implications for navigation – ultimately it was found that polar flattening would lead to a navigational error of approximately 20 miles in a trans-Atlantic crossing although at the time of the Mission it was believed it could have been as much as 300 miles. Politically the Mission provided an opportunity for the French to form an alliance with the Spanish, and to get a close look at the Spanish colonies in South America which had provided huge wealth to Spain over the preceding 200 years. Ferreiro provides a nice overview of the L’Académie des Sciences under whose aegis the mission was conducted,and of the Comte de Maurepas, French minister of the navy and sponsor of the Mission.

The core members of the Geodesic Mission were Pierre Bouguer, Charles-Marie de La Condamine, and Louis Godin they were accompanied by Spanish Naval cadets Antonio de Ulloa y de la Torre-Guiral  and Jorge Juan y Santacilia. Other members were Joseph de Jussieu (doctor and botanist), Jean-Joseph Verguin (engineer and cartographer), Jean-Louis de Morainville (draftsman and artist), Theodore Hugo (instrument maker), Jean-Baptiste Godin des Odonais and Jacques Couplet-Viguier.

Louis Godin, an astronomer, was the senior academician and nominal leader of the mission. Pierre Bouguer, was a mathematician, astronomer and latterly geophysicist: as well as the measurement of the degree of latitude he also attempted to measure the deflection of a plumb-line by the mass of a mountain – an experiment which Nevile Maskelyne was to conclude successfully in 1775, I wrote about this here. Bouguer also wrote a treatise on ship building whilst away in South America. Charles-Marie de La Condamine could best be described as an adventurer although he was also a competent mathematician and geographer, it was his more lively writing on life in South America which would have a bigger impact on their return to Europe.

The scheme for the determination of the length of a degree is to measure the length of a meridian (a line of longitude) close to the equator by triangulation, making a ground measurement baseline to convert the angular measurements of the triangulation survey into distances and a second baseline to confirm your workings; the latitudes of the ends of the triangulation survey are determined astronomically by measuring the positions of stars. I’ve read of this process before, the new thing I learnt was the method for aligning up your zenith sector with the meridian – which I’m tempted to try at home.

These measurements were done in the area around Quito, in modern Ecuador (named after the equator), the endpoints of the survey were at Quito in the north, close to the equator and Cuenca approximately 200 miles south. During the survey, through the Andes, the team scaled peaks as high as Mont Blanc (and suffered altitude sickness for their troubles) which would not be climbed for another 50 years. The survey was repeated in the early years of the 20th century and even then it took 7 years – the same length of time as the original survey, due to the transport difficulties presented by the terrain.

The work of measuring the meridian was made more difficult by the journey to get there (which took the best part of a year), the terrain and conditions when they got there (mountainous and cloudy), the poor leadership of Godin, local political machinations and the mother country cutting them loose financially. Ferreiro makes a lot of Godin’s poor leadership, some of which is justified – he spent Mission money on prostitutes and regarded the Mission funds as his own purse. Frequently the Mission split into two groups, one containing Bouguer and La Condamine and the other Godin – sometimes this is quite appropriate, in duplicating measurements for consistency whilst on other occasions it is simply fractiousness.

To a degree the Mission was scooped by measurements made above the Arctic Circle in Lapland, this mission was also promoted by the L’Académie des Sciences, led by Pierre Maupertuis (a rival of Bouguer) and Anders Celsius. It completed its work in 6 months, well before the Geodesic Mission had finished their work, discovering that the poles of the earth were flattened. However, doubts remained over the results and the full determination required the data from the equator. Bouguer presented this on his return to France, to great acclaim, showing that the earth was flattened by 1 part in 179 (later measurements showed that the flattening is actually smaller at 1 part in 298).

The Mission spawned a wide range of publications by its members, covering not only the geodesic component of the work but also regarding life and nature in South America. Ferreiro credits La Condamine’s work in particular has setting the context of how South America was viewed for quite some time after the mission. The Spanish officers also made in impact an highlighting colonial misrule back to their home country. Arguably the international collaborative elements of the Mission set the scene for the measurements of the transit of Venus later in the 18th century.

Ferreiro makes a comparison between the French Geodesic Mission, which was centrally run by the state and the British Longitude Prize, which although state funded was privately executed, implying that the former was superior. It’s not clear to me whether he’s engaging in a degree of hyperbole here, since the Mission was to some degree an organisational car-crash and was in large part funded from La Condamine’s own purse at the time. Furthermore, L’Académie des Sciences also awarded prizes – having copied the British government in this and the Royal Society was from the outset a very internationally oriented organisation. So the picture as Ferreiro presents it is something of an over-simplification.

I found the book very readable, its clearly based on a large quantity of primary source material and covers a great deal beyond the simple mechanics of the Geodesic measurements.


My Evernotes on the book are here.

Lavoisier: Chemist, Biologist, Economist by Jean-Pierre Poirier


Recently I read Vivian Grey’s biography of Lavoisier. Although a fine book, it left me wanting more Lavoisier, so I turned to Jean-Pierre Poirier’s more substantial biography: “Lavoisier: Chemist, Biologist, Economist”. Related is my blog post on the French Académie des Sciences, of which Lavoisier was a long term member, and senior, member.

This is a much longer, denser book than that of Grey, with commonality of subject it’s unsurprising that the areas covered are similar. However, Poirier spends relatively more time discussing Lavoisier’s activities as a senior civil servant and as an economist.

The striking thing is the collection of roles that Lavoisier had: senior member of Ferme Générale (commissioned Paris wall), director of the Académie, director of the Gunpowder and Saltpeter Administration, owner and manager of his own (agricultural) farms. It’s difficult to imagine a modern equivalent, the governor of the Bank of England running a research lab? Or perhaps an MP with a minor ministerial post, running a business and a research lab? In practical terms he did experimental work for a few hours each morning and evening (6-9am, 7-10pm) and on Saturdays – having a number of assistants working with him.

Lavoisier was wealthy, inheriting $1.8million* from relatives as an 11 year old he joined the Ferme Générale with an initial downpayment of about $3million. However, this provided an income of something like $2.4-4.8 million a year. On a trip to Strasbourg as a 24 year old, he spent $20,000 on books – which you have to respect. As the collector of taxes levied on the majority but not the nobility or clergy, the Ferme Générale was one of the institutions in the firing line when the Revolution came. Wealthy financiers, such as Lavoisier, bought stakes in these private companies, provided exclusive rights by the King, and made enormous rates of return (15-20%), at the same time serving the Kings needs rather poorly.

As for his activities in chemistry, Poirier provides a a good background to the developments going on at the time. Beyond what I have read before, it’s clear that Lavoisier does not make any of the first discoveries of for example, oxygen, carbon dioxide or nitrogen, nor of the understanding that combustion results in weight gain. But what he does do is build a coherent theory that brings all of these things together and overthrows the phlogiston theory of combustion. With Guyton de Morveau he develops a new, systematic, way of naming chemicals which is still used today and, as a side effect, embeds his ideas about combustion. It’s from this work that the first list of elements is produced. Furthermore, Lavoisier sees the applications of the idea of oxidation in explaining “chemical combustion” as entirely appropriate for understanding “biological combustion” or respiration. In a sense he sets the scheme for biochemistry which does not come to life for nearly 100 years, for want of better experimental methodology.

It’s interesting that gases are arguably the most difficult materials to work with yet it is their study, in particular understanding the components of air, which leads to an understanding of elements, and the “new chemistry”. Perhaps this is because gases are their own abstraction, there is nothing to see only things to measure.

The book also gives a useful insight into the French Revolution for someone who would not read the history for its own sake. The heart of the Revolution was a taxation system that exempted the nobility and the clergy from paying anything, and a large state debt from supporting the American War of Independence. Spending appears to have been decided by the nobility, or even just the King, with little regard as to how the money was raised. At one point Paris considered an aqueduct to bring in fresh water to all its citizens, but then decided that rebuilding the opera house was more important! The Revolution was a rather more drawn out than I appreciated with Lavoisier at the heart of the ongoing transformation at the time of his execution during the Terror, only to be lauded once again a couple of years later as Robbespierre fell from power and was executed in his turn.

On economics: Lavoisier was one of the directors of the French Discount Bank, during the Revolution he was involved in plans for a constitutional monarchy and amongst the ideas he brought forward was for what would essentially be an “Office for National Statistics”. The aim being to collect data on production and so forth across the economy in support of economic policy. This fits in with the mineral survey work he carried at the very beginning of his career and also on his work in “experimental farming”. Economic policy at the time alternating between protectionism (no wheat exports) and free-markets (wheat exports allowed), with many arguing that agriculture was the only economically productive activity.

It’s tempting to see Lavoisier’s scientific and economic programmes being linked via the idea of accounting: in chemistry the counting of amounts of material into and out of a reaction and in economics counting the cash into and out of the economy.

Definitely a book I would recommend! It’s remarkable just how busy Lavoisier was in a range of areas, and the book also provides a handy insight into the French Revolution for those more interested in science. I wondering whether Benjamin Franklin should be my next target.


*These are equivalences to 1996 dollars, provided in the book, they should be treated with caution.

L’Académie des Sciences


I’ve written a number of times on the Royal Society, Britain’s leading and oldest learned society, often via the medium of book reviews but also through a bit of data wrangling. This post concerns the Académie des Sciences, the French equivalent of the Royal Society. It has gone through several evolutions, and is has been one of five academies inside the Institut de France since its founding in 1795. As a physical scientist the names of many members of the Académie are familiar to me; names such as Coulomb, Lagrange, Laplace, Lavoisier, Fourier, Fresnel, Poisson, Biot, Cassini, Carnot …

The reason I’m interested in scientific societies is that, as a practitioner, I know they are part of the way science works – they are the conduit by which scientists* interact within a country and how they interact between countries. They are a guide to who’s hot and who’s not in science at a particular moment in time, with provisos for the politics of the time. As I have remarked before much of the “history” taught to scientists comes in the form of Decorative Anecdotes of Famous Scientists, this is my attempt to go beyond that narrow view.

The Académie des Sciences was founded in France in 1666 only a few years after the Royal Society which formally started in 1660. It appears to have grown from the group of correspondents and visitors to Marin Mersenne. In contrast to the Royal Society it was set up as a branch of government, directed by Jean-Baptiste Colbert who had proposed the idea to Louis XIV. The early Academy ran without any statutes until 1699 when it gained the Royal label. The Academy was based on two broad divisions of what were then described as mathematical sciences (astronomy, mathematics and physics) and “physical” sciences (anatomy, botany, zoology and chemistry) within these divisions were elected a number of academicians, and others of different grades. Numbers were strictly limited: in 1699 there were 70 members and even now there are only 236. Unlike the Royal Society, funded by member subscriptions, the Academy was funded by government – giving a number of generous pensions to senior academicians to conduct their scientific work.

The Academy avoided discussion of politics and religion, echoing the founding principles of the Royal Society, and was explicit in making links to foreign academics giving them the formal status of correspondent. This political neutrality was sustained through the French Revolution: although the Academy was dissolved for a few years at the height of the Terror and was subsequently reformed with essentially the same membership as before the revolution. Furthermore work on revising the French system of weights and measures carried on through the Revolution.

The Scholarly Societies Project has an overview of publications by- and about the Academy. The earliest scientific papers of the Academy appear in “Journal des Sçavans”, which commenced publication in 1665, shortly before the “Philosophical Transactions of the Royal Society” and therefore the earliest scientific journal published in Europe. From 1699 a sequence of work is published in “Histoire de l’Académie royale des sciences” until 1797.  Finally “Comptes Rendus Hebdomadaires des Séances de l’Académie des Sciences” has been published since 1835. Most of which are freely available as full-text digitized editions at Gallica (the French National Library).

The British government established the Longitude Prize in 1714, by act of parliament, to award the inventor of a simple and practical method for determining the longitude at sea. Subsequently Rouillé de Meslay invested a similar prize for the Academy, which commenced in 1720. This sequence of Academy prizes was awarded yearly to answer particular questions and alternated between subjects in the physical sciences and subjects in navigation and commerce. Those in commerce and navigation revolved around shipping: with questions on anchors, masts, marine currents and so forth. These prizes were open to all, not just members of the Academy. Subsequently the Academy became a clearing house for a whole range of prizes, these are described in more detail in “Les fondations de prix à l’Académie des sciences : 1714-1880” by E. Maindron.

In summary, although similar in their principles of supporting science, scientific communication and providing scientific support to the state and commerce the Royal Society and the Académie des Sciences differ in their internal structure and relationship with the state. The Academy being more closely aligned and funded by the state, certainly in formal terms, and rather more limited in its membership.

In common with the Royal Society the membership records of the Académie are available to play with and in common with the Royal Society they are in the form of PDF files which are a real pain to convert back into nicely structured data. I could engage in a lengthy rant on the inequities of locking up nice data in a nasty read-only format but I won’t!


  • Image is “Colbert présente à Louis XIV les membres de l’Académie Royale des Sciences crée en 1667” by Testelin Henri (1616-1695)
  • *Yes, Becky, I know you don’t want me to use “scientist” in reference to people living before the term was first coined in the 19th century ;-)


MacTutor History of Mathematics Archive is the best English language resource I’ve found on the Académie des Sciences. Winners of the Grand Prix can also be found on this site.

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


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.