Proposal for a book
An Element of Controversy
The Life of Chlorine in Science, Medicine, Technology and War
Hasok Chang and Catherine Jackson
Department of Science and Technology Studies
University College London
Gower Street, London WC1E 6BT
This book presents the controversial life of the chemical element chlorine, from its discovery in 1774 to the late twentieth century. It is an "object biography" that cuts through many conventional disciplinary lines, pulling together investigations in the history of science, history of medicine, economic history, military history, philosophy of science, and science policy. The studies collected here give a broad-ranging account of one of the most common yet fascinating substances on earth, and at the same time offer a unique and insightful view into the workings of science, medicine and technology in society. The settings of chlorine's life include arcane chemical debates on the nature of combustibles and acids, the desperate practical necessities of disinfection and bleaching, the battlefields of the First World War and the herbicide-ravaged jungles of Vietnam, and the attempts to look into the core of the sun by capturing the elusive neutrino.
The content of this book is based on original research carried out by undergraduate students at University College London, who are listed below as authors of individual chapters. The work has been in progress since 2000, through an innovative course in which students pass on the fruits of their research from year to year for cumulative improvement (see http://www.ucl.ac.uk/sts/chang/chlorine/C313.htm for further details). The epilogue contains the editors' account of this extraordinary pedagogical process. All contributions will be re-organised and edited carefully, to ensure coherence of content and consistency of style.
Contents (contributors to each chapter are listed in parentheses after the title)
Part A. Chlorine and the theory of matter
Chapter 1. The birth of chlorine and the death of phlogiston (Ruth Ashbee)
When the Swedish chemist Carl Wilhelm Scheele first discovered chlorine in 1774, he called it "dephlogisticated muriatic acid", or "dephlogisticated acid of sea salt" (muriatic acid in modern terms is hydrochloric acid, or HCl). But this was in the thick of the Chemical Revolution, in which Antoine-Laurent Lavoisier's oxygen theory was rapidly displacing the phlogiston theory, which was the basis of Scheele's thinking. It is tempting to conclude that Scheele was simply an adept experimenter who lacked the theoretical resources to reach a correct understanding of what he had discovered. However, our study of Scheele shows very clearly that he was a sophisticated theorist, and his interpretations do make a lot of sense in their own terms. Even if we take the modern point of view, we find that the Lavoisierian interpretation was just as wrong: Claude-Louis Berthollet, Lavoisier's colleague who studied chlorine most closely, concluded that it was "oxygenated muriatic acid". It is not simple to say which side was more correct in this debate. What we have here is a genuine case of incommensurability, which we can understand best on the basis of the ideas developed by Thomas Kuhn later in his life.
Chapter 2. Is chlorine an element? (Mårten Åkesson, Rosemary Coates, and Tamsin Gray)
In the aftermath of the Chemical Revolution, a fierce debate about the nature of chlorine continued for decades. The architects of the new chemistry, with the confidence of their general triumph, continued to uphold two beliefs about chlorine that are wholly rejected by modern science: they thought that chlorine was a compound of oxygen and muriatic acid, and that muriatic acid was a compound of oxygen and the "muriatic radical". It was only around 1820, thanks to the work of Humphry Davy among others, that chemists arrived at a consensus that chlorine was a chemical element, isolated by removing hydrogen from muriatic acid. This also meant that muriatic acid contained no oxygen, which demolished the doctrine that oxygen was the essential component of all acids, which was a centrepiece of Lavoisier's theory. This episode completes our view of the Chemical Revolution seen through the case of chlorine, in which the winners are quite as mistaken as the losers if we judge them according to modern ideas. It also illustrates the extreme difficulty of reaching clear and unambiguous theoretical interpretations of basic phenomena.
Chapter 3. Chlorine and Prout's hypothesis (Jonathan Nendick, Dominic Scrancher, and Olivier Usher)
When chlorine was recognised as a chemical element, it became important to determine its atomic weight. The best empirical values clustered around 35.5; this presented a problem for those who supported Prout's hypothesis, the idea that all atomic weights were integer multiples of hydrogen's weight (defined as 1). Prout's hypothesis is celebrated many modern scientists and historians as the anticipation of the idea that atomic nuclei are composed of a discrete number of protons and neutrons. In the end the idea of isotopes made sense of the atomic weight of chlorine, as chlorine naturally occurring on earth came to be seen as an accidental 3:1 mixture of two isotopes, weighing 35 and 37 respectively. Each isotope of was then seen to conform to Prout's hypothesis. How supporters of Prout's hypothesis dealt with chlorine before the discovery of isotopes reveals some interesting points about the scientific method, particularly in reference to the discussion of this episode by Imre Lakatos as an illustration of his methodology of "research programmes". Some chemists, by wishful thinking or experimental imprecision, estimated the atomic weight of chlorine as 36; some proposed a modification of Prout's hypothesis taking half of hydrogen as the fundamental unit; some simply put chlorine on hold and hoped for an unexpected resolution of the anomaly; others regarded chlorine as a refutation of Prout's hypothesis, and thereby discarded a promising and pioneering theoretical idea.
Chapter 4. Looking into the core of the sun (Andrew Clegg, Christian Guy, Lisa Murch, Emma Goddard, and Emily Milner)
In the 20th century chlorine found itself in the middle of yet another central debate in the theory of matter. It was predicted that the heavier isotope of chlorine (37Cl) would occasionally interact with the neutrino, the most elusive of elementary particles that had been written off as undetectable. The chlorine-neutrino interaction would produce radioactive argon atoms, which could be swept up by bubbles of helium gas, and then isolated and counted up. This fantastic scheme was realised in an experiment in which physicists buried a huge vat of dry-cleaning fluid (C2Cl4) in the Homestake gold mine in South Dakota, aiming at the first-ever detection of neutrinos emerging from the interior of the sun. The success of Homestake and other similar experiments, however, plunged physicists into a deep quandary. The detected flux of neutrinos was much less than what was predicted by the standard theory of the nuclear reactions taking place inside the sun. Debates on this issue still continue today, but physicists are now converging on the unexpected solution of "neutrino oscillations": neutrinos have a tendency to change their form in transit between the sun and the earth, lowering the detection rate where the detector is only designed to capture them in their original form. This episode also reminds us of some difficult philosophical questions about what can be considered an "observation". Physicists commonly say that they make direct observations of the solar interior by means of neutrinos, but shouldn't we really admit that we are only making a long chain of inferences going from the detection of radioactive argon to the nuclear fusion in the sun? Philosophers such as Shapere emphasise that scientific observations are routinely indirect and we have no choice but to rely on our best theories. However, if we allow theoretical inferences to form the basis of observations, then we must also say that neutrinos were observed long before Homestake.
Part B. Life, death and destruction by chlorine
Chapter 5. Obstacles in the establishment of chlorine bleaching (Olympia Brown, Saber Farooqi, Jacob Soper, and Manchi Chung)
When Scheele first isolated chlorine, he immediately noticed that it had the power to destroy "vegetable colours". On the face of it, it would seem that this should have led rapidly to industrial and commercial applications, especially given the strong demand for cheap and quick bleaching methods in the burgeoning textile industry during this time of the Industrial Revolution. The actual history was rather different -- it was a long and complex process to turn the idea into a usable and economical technology. This case reminds us of the general inadequacies of the "linear model" of technological development, according to which new discoveries spontaneously arising in pure science get straightforwardly applied to appropriate technological situations. The importance of contextual factors is shown clearly in a comparative history of chlorine bleaching in France and Britain. In France, the initial pattern of development was driven by central government, as one might expect. However, the disruptions of the French Revolution actually placed enough obstacles in the plans, and at that point private enterprise came to play a crucial role. In England the role of the state was minimal from the start, and the development of chlorine bleaching was left to the "scientist-entrepreneurs" such as James Watt, the gentlemen opportunists who played the topsy-turvy material and social world of the Industrial Revolution to their own advantage.
Chapter 6. Chlorine disinfection and the germ theory of disease (Elinor Mathieson, Fiona Scott-Kerr, and Anna Lewcock)
Chlorine kills germs. Given our familiarity with chlorine in swimming pools, water supply and household disinfectants, we might imagine that the promoters of public health would have quickly seized on the disinfecting power of chlorine and many of its chemical compounds. But actually the development and application of chemical disinfection was a long and frustrating process. Starting with the muriatic-acid fumigation of the Dijon Cathedral in 1773 by Lavoisier's colleague Louis-Bernard Guyton de Morveau, many attempts were made at using chlorine and various chlorine compounds as disinfectants, but the practices failed to take root for a century. Time and again we witness a successful employment of chlorine, by figures such as Florence Nightingale and Ignaz Semmelweis, only to become neglected and forgotten after a period. It was not until the establishment of the germ theory of contagious diseases that disinfection by chlorine or other means became truly established. Without a convincing explanation of why disinfection worked, the successful practices were discounted as accidental outcomes.
Chapter 7. Chlorine as the first chemical weapon (David Bulley, James Cambrook, Frederick Cowell, and Xuan Goh)
It is not just bacteria that are attacked by chlorine. Chlorine gas was the first major chemical weapon, introduced during the First World War. Its first battlefield use was by the German army in April 1915; retaliation in kind by the Allies followed, as did the introduction of a dizzying array of other chemicals. It may seem that the use of any available new technology in war is simply a natural thing. But there were also various reasons against the introduction of chemical weapons, including their questionable military utility and the clear prohibition of their use in the Hague Convention. Therefore, the political decision to authorise their use deserves some historical scrutiny. In the case of Great Britain, it seems that the initial aversion against chemical weapons within the government yielded to the mechanical logic of response-in-kind. This lack of deep policy-thinking is revealed in the fact that much of the decision-making on chemical warfare was delegated to Major Charles Foulkes, a relatively minor military figure put in charge of the Special Brigade for gas warfare.
Chapter 8. Ethics and public relations in chemical warfare (Nicholas Coppeard, Abbi Hobbs, Catherine Jefferson, and Chris Pitt)
Despite the apparent lack of soul-searching within the government and the military, the use of chlorine and other toxic chemicals as weapons did result in a public outcry. But was there a cogent philosophical basis for arguing that chemical weapons were morally more reprehensible than conventional weapons? If not, why did they generate such adverse public reactions? Very different ethical frameworks were applied to the question of chemical warfare by different thinkers, even within the military and governmental establishments. Against Foulkes's type of instrumental rationality of using whatever he thought would promote the military objectives, General Peyton March of the US Army objected to the use of gas because it was an indiscriminate weapon that did not preserve the principle of non-combatant immunity. The British General Sir John French deplored gas as an unchivalrous weapon, in the face of which all the character and skills of a good soldier were rendered useless. J. B. S. Haldane, renowned physiologist and active participant in gas-warfare research with first-hand experience of the effects of gas, shone the cold light of utilitarian logic on the issue by arguing that chemical weapons were actually preferable to conventional ones because they caused less suffering. Meanwhile, public reaction turned decisively against chemical weapons in the aftermath of the war. This reaction did not result simply from people's natural revulsion, but was driven by a concerted effort by the League of Nations to restore the international control of warfare after the clear violations of the Great War left the Hague Convention in tatters.
Chapter 9. The rise and fall of "chlorine chambers" against cold and flu (David Nader and Spasoje Marcinko)
For a brief period after the First World War, breathing a low concentration of chlorine was widely believed to cure and prevent influenza, the common cold, and other respiratory diseases. This "chlorine chamber" fad is perhaps one of the strangest and most fascinating episodes in the life of chlorine. Though its life was short, in its heyday the chlorine chamber was successfully showcased at the U.S. Congress and counted even President Calvin Coolidge among its grateful users. Who promoted this bizarre idea, and why? The birth and spread of chlorine as a therapeutic can primarily be seen as an attempt by the US Chemical Warfare Service to gain public and governmental support for continuing research into chemical weapons. But why was the idea not immediately discredited, once tested out? Interestingly, it does seem that chlorine-inhalation was just as effective (or ineffective) against the flu and the common cold as any other available treatment. At the time little was known about viruses, and treatments were rudimentary. There was clear space for innovative ideas after the influenza epidemic between 1915 and 1920, which killed many thousands of people; the medical establishment was in crisis, and chemists were enjoying newly found prestige from their role in the war. But soon enough the Chemical Warfare Service found in insecticides a much more promising instrument of self-promotion, and the chlorine chamber was quietly dropped.
Chapter 10. War and the scientific community (Sam Raphael, George Kalpadakis, and Daisy O'Reilly-Weinstock)
If science changed the face of warfare, warfare changed science just as much. Historians have clearly documented the changes introduced to science as a result of the Manhattan Project and other large-scale wartime projects. In the life of chlorine, there are two phases in which the impact of war on science became clear. During the First World War, the necessity to understand the physiology of chlorine and other poison gases brought the physiologists out of their relative isolation, making them an integral part of political decision-making and changing the way their own community was structured. A less benign and more disruptive case was the dispute over the use of chlorine-based herbicides (including the notorious "agent orange") in Vietnam by the US military, which pitted "official" and "lay" scientists against each other in a battle for public credibility. In the course of this episode, there was a shift of perceived authority from the government to the lay scientific community. Interestingly, this "authority shift" was not the result of any significant new scientific knowledge being discovered by the winning side. An important context of the shift was what Ulrich Beck terms "reflexive modernization", in which more and more groups compete for authority, resulting in a widespread consciousness of the inherent plurality of knowledge.
Chapter 11. The noisy reception of Silent Spring (Kimm Groshong)
The controversial herbicides discussed in the last chapter are only a small group within the class of organochlorines, or organic chlorine compounds, which also include nerve gases, dioxin, and DDT. Some environmentalists have called for them to be phased out entirely. The uproar about organochlorines began most distinctly with the publication of Rachel Carson's 1962 masterpiece, Silent Spring, which delivered a scathing exposé on the effects of DDT. Despite her extensive research and expertise, Carson's text was heavily criticised as unscientific emotionalism offered by a non-scientist. But very few attempts were made to point out specific problems in the text, and most scientists now agree that there were no major inaccuracies. A question then arises as to how these early attacks were motivated, and why they still echo widely in commentaries on Silent Spring today. The chemical industry and its associates had no other means of downplaying Carson's book other than repeating as many times as possible (in the public eye) the unsubstantiated view of Silent Spring's inaccuracy, bias, and reliance on rhetoric. The effects of such an intense campaign are long-lasting. Many of those who published critical comments and reviews of Silent Spring were enraged by Carson's attempt to awaken the public about the extent to which it was blindly ceding power to the growing science-industry-government complex. The noisy response was therefore a natural result of the context into which the book was published.
Epilogue: Turning an Undergraduate Class into a Professional Research Community
This book is the product of a radical educational initiative. Despite many recent efforts at reform, our educational systems still tend to be based on the notion that students are there to be trained by passively acquiring knowledge that already exists, before they can produce original work. We believe that the processes of learning and knowledge-production can be soldered into one. Even pioneering programmes of undergraduate research tend to make it a reserve of the best and the brightest. We have made it a routine part of an ordinary undergraduate programme from which any competent and hard-working students can benefit. This is made possible by the mechanism of inheritance, in which successive groups of students gradually expand and improve on one body of work. Also helpful is the insistence that the students should form a community of researchers, which also connects up strongly with the professional research community existing "out there".
In the fields of Ypres one spring day in 1915, Allied troops lay writhing in agony from a deadly gas attack that opened a new chapter in the history of warfare. Nine years later President Calvin Coolidge of the United States sat in a specially designed chamber breathing the same gas, and pronounced himself much relieved from his cold afterwards. That gas, yellow-green, suffocating and corrosive, was isolated for the first time in 1774 by the Swedish chemist Carl Wilhelm Scheele, who called it "dephlogisticated muriatic acid". After half a century of fierce academic debates the substance was identified as a new chemical element, and it has continued working its way into various aspects of our lives to this day. In fact it was always with us, being one half of common salt (sodium chloride) among other things, though we humans were very slow in recognising its identity.
This book tells the story of chlorine, one of the most common yet unusual substances that make up our physical universe. The story is full of wonder, mystery, danger, and most of all controversy, both intellectual and political. And like any good biography, it also tells much about the society in which the hero or heroine lived. Thus our story of chlorine's life is also the story of how science developed in the last two centuries and how it became such an integral part of modern life through its technological, medical and military applications. The time span we cover is roughly two centuries; although it is impossible to be exhaustive, our selection of events and issues will portray a well-rounded picture of an extraordinary life.
In disciplinary terms, this is first of all a work of history of science. But our subject has forced us to cross many boundaries, and various parts of the book will be of interest to historians of technology, medicine and war as well, and also to philosophers and sociologists. In short, we present this book to all readers interested in science, its nature, its history and its relevance in human life.
The studies contained in the book were carried out by five successive cohorts of undergraduate students in the Department of Science and Technology Studies at University College London, each year's group building on the work of the previous one. As the research was done by undergraduate students still relatively free from the need to sound learned yet eager to rise up to the highest academic standards, we believe we have reached a happy combination of rigor and accessibility. In the Epilogue we give a more detailed description of this fascinating and exciting experience, which will be of interest to those concerned with the practice and theory of higher education. The editors are responsible for the overall organisation of the book and the presentational work to ensure consistency in style, as well as some follow-up research to fill in small gaps. However, credit for the content of the book belongs unequivocally to the authors of the individual chapters, and they are also wholly responsible for the lively spirit of the whole enterprise that shines through all of the chapters.
Comments on related books
In relation to many other titles in the area of history of science and popular science, our proposed book is distinguished by its object-focus. "Object biography" has only recently become a recognisable genre in popular science and history, as seen in the successes of John Emsley, The Shocking History of Phosphorus (Macmillan, 2000), and Mark Kurlansky, Cod: A Biography of the Fish that Changed the World (Penguin, 1997). Other examples include Philip Ball, H2O: A Biography of Water (Weidenfeld and Nicolson, 1999), and John S. Rigden, Hydrogen: The Essential Element (Harvard, 2002); an early pioneering example is Robert P. Multhauf, Neptune's Gift: A History of Common Salt (Johns Hopkins, 1978). We believe that object biography is a highly informative mode of analysis and synthesis whose potential has not yet been explored fully (it is still a tiny genre compared to traditional personal biography).
Our proposed book is distinct from most object biographies in several ways. First, we exploit fully the interdisciplinary potential of the genre. To reach a reasonably complete view of the life of chlorine, we were forced to forge links between history of science, history of technology, and history of medicine; between political history, economic history, military history, and intellectual history; between various national histories; and between history of science, philosophy of science, and science policy. Our collective mode of work was very suitable for managing the necessary breadth of material. Second, our book is based on highly original material based on uncompromisingly rigorous academic work, including a good deal of archival research; testimony on the high standard of the work can easily be found, for instance in the comments of the external examiners who have scrutinised the students' work over the years. Third, we have sought to give overall coherence to the book, in order to avoid producing a collection that is merely a set of various interesting stories. In a personal biography, one might say that the common line that runs through the various stories of an individual's life is his/her character; here we find that the highly reactive chemical character of chlorine is largely responsible for its eventful life, both in chemical theory and in its often destructive practical applications. That leads naturally to another coherent thread running through our book, which is our historiographical focus on studying controversies.
Our book is also very distinctive in that it is a product of a unique educational experiment. Recently there has been a great deal of discussion on encouraging undergraduate students to engage in original research, and integrating teaching and research. Our project at University College London is at the forefront of this general movement, and our book will demonstrate clearly the feasibility and desirability of research-based instruction. Its quality and accessibility will make it an ideal showcase to encourage students and teachers in numerous other institutions to take up similar challenges.
Brief CV of editors
Senior Lecturer in Philosophy of Science, University College London (since January 1995)
Previously, Research Associate in the Department of Physics, Harvard University (July 1993-December 1994)
PhD in Philosophy, Stanford University (1993)
Previous Publications: Inventing Temperature: Measurement and Scientific Progress (New York: Oxford University Press, 2004), and numerous articles in the areas of history of science and philosophy of science, particularly regarding the physical sciences since the eighteenth century.
Teacher of Chemistry, University College London
Previously, Head of Chemistry, Wimbledon High School GDST (2000-02)
Previously, IT Consultant/Project Leader, Shell International Petroleum Co. Ltd (1990-97)
PhD in Biological Organic Chemistry, University of Cambridge (1988)
MSc in History of Science, Medicine and Technology, University College/Imperial College London (2004)
Estimated time of completion
The last run of the course in which the research is being carried out will finish in March 2005. Preliminary editing work will be carried out before then, and we plan to produce the completed manuscript by September 2005.
The opening paragraphs of this proposal could be used as the basis for a jacket blurb or in catalogues.
An important addition to the new exciting genre of object biography
A unique product of research by undergraduate students, accomplished through an inspiring educational experiment at University College London
Original work combining rigour and accessibility
Broad-ranging discussion of fascinating episodes from the history of science, medicine, technology and war