Shifting Scales. Microstudies in Early Victorian Britain

Shifting Scales. Microstudies in Early Victorian Britain H. Otto Sibum1 In 1847 James Joule gave one of his rare public lectures in which he remarked that living force is not destroyed by friction or collision of bodies: “We may conclude, then, with cer- tainty, that these motions of air and water, constituting living force, are not annihilated by friction. We lose sight of them, indeed, for a time; but we find them again reproduced.”2 In this paper I would like to answer the question what was the context of experience which led Joule to this conclusion, one that implicitly presumed a firm knowledge about the microcosm of interacting and transforming natural forces and which leading natural philosophers could not accept. I will show that Joule’s microscopic vision of heat was rooted in his gestural knowledge derived from experience in manipulating heat processes and further developed through instrumental practices and sensuous economies shared by a small collective of researchers at Manchester.3 In the first section I will give a detailed account about practices of collaboration between James Joule and John Benjamin Dancer during the period from 1844 until 1846, a time in which both were engaged in producing a new mercury thermometer which would measure with a degree of accuracy unheard of in that time. In this “extreme sensitive” instrument Joule saw both his high standards of precision measurement and the wish to outwit nature’s capricious behaviour by display- ing her latent heat movements materialised. In the following section I will focus on John 1. This paper was presented at the workshop ”Varieties of Scientific Experience” held at the Max Planck Institute for the History of Science, Berlin 1997, at Universities of Princeton , Harvard and Utrecht as well as the Science Museum London. I am grateful to all participants for the stimulating responses. I’am quoting from sources held at the Royal Society, London; Manuscript collection, Cambridge University Library (hereafter CUL); Manchester University Library and Public Library; Joule archive, Library of University of Manchester Institute of Science and Technology (hereafter UMIST); William Thomson archive, Glasgow University Library (hereafter GUL); H. Rowland manuscripts, Johns Hopkins Univer- sity Library (hereafter JHU) and am grateful to have permission to do so. 2. ”James Prescott Joule, ”On Matter, Living Force and Heat.” A lecture at St. Ann’s Church Reading Room; published in the Manchester Courier newspaper, May 5 and 12 (1847); reprinted in The Scien- tific Papers of James Prescott Joule (hereafter SPJ ) vol. 1 (London 1884) 265-276, 269. Amongst a few other traces historians of science have taken this lecture as firm evidence for their claim that Joule is one of the co-discoverers of the energy conservation principle. 3. For further details on the historical embodiement of James Joule’s working knowledge, elsewhere con- ceptualised as gestural knowledge see H.Otto Sibum, “Les Gestes de la Mesure. Joule, les pratique de la brasserie et la science”, Annales Histoire, Sciences Sociales, 4-5 (1998): 745-774, and Sibum, ”Ex- perimental History of Science”, in Museums of Modern Science, ed. Svante Lindqvist (Canton 2000), pp. 49-56. H. OTTO SIBUM Benjamin Dancer’s research practices, which led him to develop microphotography, and also show a common underlying structure with Joule’s working knowledge, specifically a technique which I shall call shifting scales. I will then describe Joule’s research practice and argue that his technique of shifting scales provided not only the means to construct and use a new instrument and experimental arrangements but also to propose a micro- physical theory of heat. In the following section I will compare Joule’s practice with W. Thomson’s approach to the same thermometric issues. The reader will again identify the underlying structure of shifting scales and I will show that in accordance with his working knowledge Thomson proposed an absolute temperature scale but missed out crucial in- sights about the microscopic nature of heat which Joule soundly derived from his se- quence of experimental arrangements. Finally I will show that in encounters with various representatives of different knowledge traditions Joule did not succeed in establishing his microscopic view because Joule’s audience did not share his context of experience. Only gradually through the amalgamation of these two different knowledge traditions, repre- sented through Joule and Thomson, was the dynamical theory of heat established. ‘Nicety of Attention’ “There are probably few sights more pleasing to one who has been brought up in factories than to watch a skilful workman engaged in ex- ecuting a piece of work which requires absolute mastery over the tools that he uses, and demands that they should have the constant guiding of his intelligent mind. Handicraft work of such a kind borders upon the occupation of the artist and to see such work in the course of execution is, as I have said, a source of pleasure.”4 During the years 1844 and 45 the scientific brewer James Joule realised that a collaboration with the virtuoso instrumentalist John Benjamin Dancer could lead to a major achievement in constructing new instruments for scientific research. Since his arrival in 1842 Joule had been one of the regular customers in Manchester’s new instrument mak- er’s shop at Cross Street (near his own brewing premises) but didn’t feel obliged to men- tion the gentleman Dancer in his publications which had only been possible through the use of his excellent tangent galvanometer, even ordered by William Thomson shortly after 4. F.J. Bramwell, “On Prime-Movers”, Conferences held in connection with the Special Loan Exhibition of Scientific Apparatus, Vol. 1. Physics and Mechanics, (London 1876): 348-380. 2 SHIFTING SCALES the encounter with Joule in Oxford in 1847.5 But from 1844 Joule spent several mornings over longer periods in Dancer’s workshop discussing problems of heat measurement and the design of a new mercury thermometer able to display heat. Both shared an attitude towards experimental practice which the brewer Joule understood as “doing with care”, a literal derivation of the Latin word “accurare”. This was a moral economy of research which demanded “nicety of attention or performance” carrying with it the values of the craft tradition according to which much effort is spent in taking care of the particulars, those minute details which inhabit the material world. To Joule, nicety of attention meant first of all a careful exam- ination of his working objects in order to achieve optimal arrangements to perform in. For his heat measurements Joule determined the specific heats of flint glass used for the construction of thermometers, and the specific heats of brass and copper, materials used for his fluid friction experiments. In a word, he derived knowledge from experiencing every circumstance and material condition relevant for the experimental performance. But such preparatory work could not substitute for the experimenter’s competence performing a proper measurement. This personal or collectively acquired gestural knowledge derived from experience was the sole standard against which artisans and virtuosi instrumentalists like Dancer and Joule judged their workmanship. Recent historical research has shown that the design and especially his performance of experiments had prof- ited extremely from his participation and enculturation in brewing culture. It led him to acquire a specific gestural knowledge in taking heat measures which included the right timing for taking measurements and a proper placement of the thermometer in order to measure the air temperature or the manner of taking the right temperature of the water in the copper vessel. He had incorporated working rhythms of a kind which now governed his experimental practice of properly immersing the thermometer into the water so that it indicates the correct temperature of the water.6 These forms of working knowledge of manipulating objects — the virtuosity in changing arrangements — derived from experience Joule and Dancer recognised in each other’s work. 5. Two tangent galvanometers are held in the Glasgow University Archive, Hunterian Museum. Both were made by Dancer under the direction of Joule in the 1840s. The larger one (J.5.) is a replica of the tangent galvanometer Joule had used and described in his 1843-44 publication “On the Heat Disengaged in Chemical Combinations”, in SPJ, vol. 1, pp. 205-235, communicated to the French Academy in 1846. The second one (J.6.) is a much smaller one in construction and was used by Joule himself. See G. Green and John T. Lloyd, Kelvin’s Instruments and the Kelvin Museum, (Glasgow 1970), p. 53. 6. Indeed, Joule’s whole choreography of the performance of measuring heat was to a large degree an im- print of his brewing practice. See Sibum, “Les Gestes de la Mesure”, op.cit. (note 3); and Sibum, “Work- ing Experiments: A history of Gestural Knowledge”, The Cambridge Review, 116, no. 2325 (1995): 25- 37. No wonder that the set up of the paddle wheel experiment turned out to be a small scale model of the brewers mash tun and previous related experiments like the one to determine the friction of fluids by pressing water through narrow tubes was an adaptation of a well known arrangement in brewing, the refrigerator to cool down the worts by passing cold water through narrow pipes mounted at the bottom of the vats. 3 H. OTTO SIBUM During this collaboration the most sensitive and precise thermometer produced in the country was made. The scientific optician Dancer provided a calibrating device which he himself called the “travelling microscope”, a device which could be moved horizontally by rotating a screw. The distance of travel could be determined from a graduated disc at one end of the screw.

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