Physics at Work: Experiment and the Knowing Body of the Scientist
Over the last decade, historians of science have shifted their attention to look beyond official texts. Aspiring to understand what scientists did and not merely what they have written, they have drawn attention to the silent witnesses of the past: instruments, laboratory architecture, personal diaries, lab notes and field notebooks, collections of strange objects: these and other humble remnants – not monuments – of the past have become valuable sources for understanding the hands-on processes by which science is made.
This project is inscribed within this problematique, and focuses on the knowing body of the scientist. I have re-interpreted an important historical episode in early Victorian experimental thermodynamics by combining historical scholarship with the reworking of experimental practice. Previous scholarship has repeatedly emphasized the remarkable achievements of the Manchester gentleman James Joule in determining the mechanical equivalent of heat – a scientific fact, which soon became the building block of the British science of energy and made him known as the co-discoverer of the principle of energy conservation. Retrospectively Joule’s outstanding experimental technique in making heat measurements has been conventionally attributed to his “magical accuracy” or semi-mystical kind of tacit or personal knowledge.
A minute reconstruction of Joule’s laboratory work – including the performance of this experiment using a replica – has shown, however, that his local experimental practice was in fact an amalgamation of different non-literary knowledge traditions. His active participation in running the largest Manchester brewery – which was undergoing tremendous changes from being a craft tradition to become an industrial production site – made the brewery a cultural resource where he acquired his refined techniques of temperature measurement. Moreover, in collaboration with the Manchester optician and scientific instrument maker J.B. Dancer, Joule produced the most precise thermometer in Britain at the time. The reconstruction of this hitherto unrecognized web of practitioners’ knowledge demonstrates that the resources for Joule’s experimental knowledge were available in early Victorian culture.
Yet producing knowledge is never enough by itself. Within this collective, Joule worked out a new theory of heat, but his experimental knowledge did not match the established standards of scientific knowledge. Outside his small community, it was initially regarded as embodied, local – and therefore sharply distinguished from scientific knowledge which was cerebral, rational and communicable through a scholarly text. Furthermore, Joule’s new scientific fact did not travel easily. Historical investigations of the way in which Joule’s experiment was replicated in selected centers of European and North American science point to a continuing struggle over the practices of determining this fact and its meaning. A detailed analysis of the various practices of knowledge exchange between the rising community of scientists throughout the second half of the 19th and early 20th century shows how Joule’s numerical fact became collectively embodied knowledge. This long-term process of achieving practical and theoretical agreement about the value and the meaning of this fact is directly connected with the establishment of experimental physics as an academic discipline in Europe and North America.
