The ‘triumph of the anti-phlogistians’ is a familiar story to the historians and philosophers of science who characterize the Chemical Revolution as a broad conceptual shift. The apparent “incommensurability” of the paradigms across the revolutionary divide has caused much anxiety. Chemists could identify phlogiston and oxygen, however, only with different sets of instrumental practices, theoretical schemes, and philosophical commitments. In addition, the substantive counterpart to phlogiston in the new chemistry was not oxygen, but caloric. By focusing on the changing visions (...) of chemical body across the revolutionary divide with a more sensitive probe into the historical actors’ material manipulations and linguistic usage, we can historicize their laboratory realities and philosophical agenda. An archeology of chemical bodies that configures the fragile stability of the material worlds chemists created in succession promises a philosophical horizon that would recognize our hybrid (natural–artificial) environment as an evolving investigative object of science. (shrink)

The paper illustrates how organic chemists dramatically altered their practices in the middle part of the twentieth century through the adoption of analytical instrumentation — such as ultraviolet and infrared absorption spectroscopy and nuclear magnetic resonance spectroscopy — through which the difficult process of structure determination for small molecules became routine. Changes in practice were manifested in two ways: in the use of these instruments in the development of ‘rule-based’ theories; and in an increased focus on synthesis, at the expense (...) of chemical analysis. These rule-based theories took the form of generalizations relating structure to chemical and physical properties, as measured by instrumentation. This ‘Instrumental Revolution’ in organic chemistry was two-fold: encompassing an embrace of new tools that provided unprecedented access to structures, and a new way of thinking about molecules and their reactivity in terms of shape and structure. These practices suggest the possibility of a change in the ontological status of chemical structures, brought about by the regular use of instruments. The career of Robert Burns Woodward provides the central historical examples for the paper. Woodward was an organic chemist at Harvard from 1937 until the time of his death. In 1965, he won the Nobel Prize in Chemistry. (shrink)

Some recent philosophers of science have argued that chemistry in the nineteenth century “largely lacked theoretical foundations, and showed little progress in supplying such foundations” until around 1900, or even later. In particular, nineteenth-century atomic theory, it is said, “played no useful part” in the crowning achievement of nineteenth-century chemistry, the powerful subdiscipline of organic chemistry. This paper offers a contrary view. The idea that chemistry only gained useful theoretical foundations when it began to merge with physics, it will be (...) argued, is based on an implicit conception of scientific theory that is too narrow, and too exclusively oriented to the science of physics. A broader understanding of scientific theory, and one that is more appropriate to the science of chemistry, reveals the essential part that theory played in the development of chemistry in the nineteenth century. It also offers implications for our understanding of the nature of chemical theory today. (shrink)

Among the many groups of scholars whose work now illuminates science, technology and medicine (STM), historians, it seems to me, have a key responsibility not just to elucidate change but to establish and explain variety. One of the big pictures we need is a model of the varieties of STM over time; one which does not presume the timeless existence of disciplines, or the distinctions between science, technology and medicine; a model which is both synchronic and diachronic, and both cognitive (...) and social. To that end, this brief paper presents a historical typology of STM from about 1700 to the present by focusing on four ‘ideal’ socio-cognitive types – four knowledge structures which correspond to four sets of social relations. To some extent these are period specific, but they do not have to be – hence, one may hope, the flexibility and usefulness of the model. (shrink)

In this paper it is performed a historical account of the theoretical roots that grounded the following four key basic ideas of chemical equilibrium: ‘incomplete reaction’, ‘reversibility’, ‘equilibrium constant’ and ‘molecular dynamics’. These notions developed in nineteenth-century as a consequence of the evolution of the concept of chemical affinity. The discussion begins with the presentation of the earliest affinity table [‘Table des rapports’] published in 1718 by Geoffroy. Afterwards, it is examined Bergman’s compilation. The theory supporting this arrangement assumed that (...) chemical displacement reactions were complete and could not be reversed. It is analysed how Berthollet’s model showed the inadequacy of this view. His new conceptual considerations established that the amount of the substances involved in a reaction was an essential factor determining its direction, which accounted for the early concepts of incomplete reaction and reversibility. Guldberg and Waage specified the role of mass in chemical equilibrium reactions as they considered the concentrations of the chemicals involved, formulating the first chemical equilibrium mathematical equation that approximates what is called nowadays chemical equilibrium constant. Finally, it is presented how Pfaundler was the first to consider the kinetic theory in the interpretation of the macroscopic properties of equilibrium reactions. (shrink)