PHILOSOPHERS OF FIRE An Illustrated Survey of 600 Years of Chemical History for Students of Chemistry William B. Jensen University of Cincinnati i Oesper Collections Cincinnati 2003 PHILOSOPHERS OF FIRE An Illustrated Survey of 600 Years of Chemical History for Students of Chemistry William B. Jensen University of Cincinnati i Oesper Collections Cincinnati 2003 Copyright ! 2004 William B. Jensen Oesper Collections in the History of Chemistry University of Cincinnati Cincinnati, OH 45221-0172 Table of Contents Introduction ! 1 Chemistry in the Renaissance I. ! The 15th Century: Our Protochemical Heritage ! 12 II. ! The 16th Century: The Impact of Medicine & Metallurgy ! 31! III.! The 17th Century: Chymistry Institutionalized & Corpuscularized! 41 Chemistry in the Eighteenth Century IV.! The Chemist Individualized ! 57 V. ! The Pneumatic Revolution ! 67 VI. ! States of Matter & Chemical Composition ! 79 VII. !Chemical Affinity ! 109 Chemistry in the Nineteenth Century VIII. The! Rise of the Professional Chemist ! 119 IX. ! The Standardization of Laboratory Practice ! 135 X. ! Molecular Composition & Structure ! 158 XI. ! Equilibrium, Thermodynamics & Kinetics ! 184 Chemistry in the Twentieth Century XII.! Specialization Rampant ! 213 XIII.!The Instrumentation Revolution ! 220 XIV.! The Electrical Theory of Matter ! 246 XV. !The Electronic Theory of Reactivity ! 284! Dedicated to RALPH E. OESPER AARON J. IHDE DEREK A. DAVENPORT Each of whom made this possible after their own fashion There is no question that we can train a chemical technologist without teaching him any history of chemistry and he may be a very good technologist indeed. I would argue with equal vehemence that we cannot educate a chemist without history of chemistry. I am interested in, and I believe most of us are, in the education rather than the training of chemists. The person who is merely trained to carry out analyses or syntheses can do his job quite satisfactorily without much chemical theory or any history of chemistry. On the other hand, the chemist who is in a position of responsibility for the planning of investigations needs to know something about the past history of chemical investigation and the development of chemical thought. Without such knowledge he is merely a technologist. Aaron J. Ihde 1971 A retrospect of the past, especially in the exact sciences, alone affords a proper comprehension of what is accepted today. It is only when we are acquainted with the theories which preceded those accepted at present, that the latter can be fully understood; because there is almost always an intimate connection between them ... But quite apart from this real advantage of history, which thus, in my opinion, leads to a clearer understanding of our present position, yet another advantage may be adduced which is perhaps of still greater value to the student: namely the accurate estimation of the value of theories. An examination of the past shows the mutability of opinions; it enables us to recognize how hypothe- ses, apparently the most securely established, must in the course of time be abandoned. It leads us to the conviction that we live in a state of continuous transition; that our ideas of today are merely the precursors of others; and that even they cannot, for any length of time, satisfy the requirements of science ... Further, by the study of history, our faith in authority is diminished – a faith which produces pernicious effects by obstructing the way for any original devel- opment of the individual. Albert Ladenburg 1900 Introduction Beware the historian in search of a novel interpretive thesis. His propensity to elevate what is in reality an historical footnote into a major revisionist theme means that there is no greater corruptor of historical fact and common sense. Wallace L. Selleck This textbook has evolved out of the one-quarter survey course in the history of chemistry which I have been offering to the seniors and graduate students in the Department of Chemistry at the University of Cincinnati for the last 20 years. The purpose of this course is to provide a brief historical outline of the evolution of modern chemistry for students of chemistry. Since the intent is to sketch this evolution in the broadest possible manner, neither the individual development of specific theories and experimental tech- niques, the larger political and social context of these discoveries, nor the various philosophical issues that were involved, are discussed in great detail. Rather the goal is to provide a skeleton framework of significant names, dates, and key historical transi- tions on which this detail can be arranged at a later date, whether acquired through the independent reading of specialist monographs on the history of chemistry or the taking of more advanced courses. ! Like a reference work, a good textbook should be tightly organized in order to facilitate rapid access to significant names, events, and dates. Unlike a reference work, however, it must be selective, rather than comprehensive, in its coverage. This selec- tivity is constrained not only by the comparative importance of the various topics but also by the fact that few chemistry departments are willing to devote more than a single quarter or semester to a history of chemistry course. ! Like a specialist monograph, a good textbook should also provide context for these names, events, and, dates by pointing out significant trends and summarizing interpretive conclusions. Unlike a specialist monograph, however, it cannot present the detailed arguments supporting these trends and conclusions nor indulge in nuanced discussions of subtle distinctions or qualifications. In - 1 - PHILOSOPHERS OF FIRE the interests of clarity and brevity, these summarized, albeit often oversimplified, conclusions and characterizations must stand on their own. ! Like a popular history intended for the lay public, a good text- book should be readable. Unlike a popular history, however, it does not shy away from using technical terminology, equations, and formulas or from employing various organizational and scholarly devices, such as sectional headers, summary tables, graphs, and footnotes. ! I point out these obvious distinctions between a textbook, on the one hand, and a reference book or specialist monograph, on the other, because the textbook appears to be a literary form that has apparently disappeared from the repertoire of the modern historian of science, and I want to make certain that there is no misunder- standing as to the nature and purpose of this book. Not only is it a textbook, rather than a reference book or an interpretative essay, it is also an outline or survey which takes a traditional internalist approach to the history of chemistry, and is explicitly intended for readers having a basic understanding of the fundamental concepts and techniques of modern chemistry rather than for the lay public. ! This neglect of the textbook is undoubtedly connected with the kinds of historical questions that are of most interest to profes- sional historians of science. An introductory survey deals with only the most rudimentary of these – namely with the questions of when certain concepts and techniques became dominant in science and which scientists played a prominent role in that rise to domi- nance. If the historian asks the further question of how these concepts and techniques were discovered, then the situation rapidly becomes more complex and topics, which in an introduc- tory outline consume only a paragraph and which make mention of only one or two names, suddenly expand to the size of chapters or entire books. Further complications arise from the fact that modern historians are seldom content to base their accounts of discovery on the published record but rather seek to discover unpublished correspondence, personal journals, and laboratory notes which might shed further light on these questions. These unpublished documents are frequently fragmentary, lacking a proper context, and chronologically ambiguous, thus tempting the - 2 - INTRODUCTION historian to unrestrained speculation. In addition, they frequently contradict the final published accounts. Though common sense would dictate that the published accounts represent the author’s final and considered opinion on the subject in question, whereas the unpublished documents are preliminary drafts or paths subsequently rejected, recent historians have tended to invert this conclusion and to claim that the unpublished documents represent the true picture, whereas the published accounts are little more than intentional misrepresentations. As a result, the recent lit- erature in the history of science has been deluged with highly speculative, and often quite questionable, revisionist accounts of major scientific discoveries. ! If one moves beyond these questions to the further question of why a given concept triumphed over its competitors and became dominant at a particular time and place, rather than earlier, later, or elsewhere, then things move from the realm of speculation into the realm of acrimony. Attempts to answer such questions range from those who believe in the scientific method and that certain concepts triumph because of their superior explanatory powers, to those who advocate a strict social constructionist approach and maintain that the dominance of one concept versus another is merely a matter of intellectual fads dictated by the larger cultural milieu. Though common sense would suggest that the true reasons probably involve a mixture of these