‘To reason by means of images’: J. J. Thomson and the mechanical picture of nature

References

• Some aspects of Thomson's work dealt with by other historians. On his atomic model of the 1900s, see Heilbron J.L. Kuhn T.S. The genesis of the Bohratom Hist. stud. phys. sci. 1969 1 211 290 and R. E. Kohler, jr., ‘The origin of G. N. Lewis's theory of shared pair bonds’, Hist. stud. phys. sci., 3 (1971), 343–376; on Thomson's theory of light, see R. McCormmach, ‘J. J. Thomson and the structure of light’, Brit. jour. hist. sci., 3 (1967), 362–387; and on Thomson's reaction to quantum physics, see the above papers and R. H. Stuewer, The compton effect: turning point in physics (New York, Science History Publ., 1975), 318–321. Other references are cited below.
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• Thomson , J.J. 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 233 – 244 . (p. 233).
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• Thomson , J.J. 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 233 – 233 .
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• Topper , D.R. 1971 . Commitment to mechanism: J. J. Thomson, the early years . Archive hist. exact. sci. , 7 : 393 – 410 . A short discussion of this matter is given in M. Jammer, Concepts of force (Cambridge, Mass., Harvard Univ. Press, 1957), 243. For other attempts at a mechanical explanation, see M. J. Klein, ‘Mechanical explanation at the end of the 19th century’, Centaurus, 17 (1972), 58–82; and D. F. Moyer, ‘Energy, dynamics, hidden machinery: Rankine, Thomson and Tait, Maxwell’, Stud. hist. phil. sci., 8 (1977), 251–268.
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• Thomson never published his dissertation; the essence of it was presented in a course of lectures delivered at the Cavendish Laboratory in 1886. I have attempted to locate the dissertation, but without success: it is not in either the University Library, Cambridge, or Trinity Library, Cambridge; even J. J.'s son, Sir George Paget Thomson, did not know where it was located. Hence, I ruefully conclude that it is not now extant. However, material from it was published in ‘Some applications of dynamical principles to physical phenomena’ (parts I and II) Phil. trans. Roy. Soc. London 1885 176 307 342 178 (1887), 471–526; and in Applications of dynamics to physics and chemistry (London, Macmillan, 1888).
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• Topper . 1971 . Commitment to mechanism: J. J. Thomson, the early years . Archive hist. exact. sci. , 7 : 406 – 406 . and 408.
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• Maxwell , J.C. 1891 . A treatise on electricity and magnetism , 3rd ed. Vol. 2 , repr. Dover, New York, 1954), vol. 2, chapter 5–9. For a discussion of this see Topper (footnote 4), 396–397; and T. K. Simpson, ‘Some observations on Maxwell's Treatise on electricity and magnetism’, Stud. hist. phil. sci., 1 (1970), 249–263.
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• Maxwell . 1891 . A treatise on electricity and magnetism , 3rd ed. Vol. 2 , 200 – 200 . 2 vols.
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• Heimann , P.M. 1970 . Maxwell and the modes of consistent representation . Archive hist. exact sci. , 6 : 171 – 213 . Heimann pinpoints this reintroduction of the lines of force in Maxwell's ‘Note on the electromagnetic theory of light’ (1868) and his Elementary treatise on electricity (written after the Treatise and published posthumously in 1881). The ‘Note’ may be found in J. C. Maxwell. The scientific papers of James Clerk Maxwell (ed. W. D. Niven: 2 vols., New York, Dover, 1965), vol. 2, 137–143.
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• The phrase ‘construirbar Vorstellung’ was used by Gauss in a letter to Weber (19 March 1845), and is published in Carl Friedrich Gauss Werke Göttingen 1863–1933 12 vol. 5 (1867), 629. Maxwell mistranslated the phrase as ‘consistent representation’ in his Treatise (footnote 7), vol. 2, 490. He also used it in ‘On the dynamical evidence of the molecular constitution of bodies’ (1875) without translating it: ‘To form what Gauss called a “construibar Vorstellung” of the invisible process of electric action is the great desideratum in this part of science’ (Maxwell, Papers (footnote 9), vol. 2, 418–438 (p. 419)). Thomson's use of the phrase occurs in his Notes on recent researches in electricity and magnetism (Oxford, Clarendon, 1893), 1, where he translates the phrase as ‘concrete representation’. He also used the term ‘Vorstellung’, without translating it, in ‘On the chemical combination of gases’, Phil. mag., (5) 18 (1884), 233–267, (p. 234).
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• Heimann . 1970 . Maxwell and the modes of consistent representation . Archive hist exact sci. , 6 : 174 – 174 .
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• Maxwell's original paper ‘On Faraday's lines of force’ (1855–56), and his paper on the model of electromagnetism, ‘On physical lines of force’ (1861–62) are reprinted in his, Maxwell J.C. The scientific papers of James Clerk Maxwell Niven W.D. Dover New York 1965 1 155 229 2 vols. and 451–513 respectively.
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• Heimann . 1970 . Maxwell and the modes of consistent representation . Archive hist exact sci. , 6 : 174 – 174 .
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• Kargon , R. 1969 . Model and analogy in Victorian science: Maxwell's critique of the French physicists . Jour. hist. ideas , 30 : 423 – 436 .
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• See, for example, Fourier J. The analytical theory of heat Cambridge University Press 1878 (trans, from the original 1822 edition by Alexander Freeman repr. New York, Dover, 1955). See also the two articles by J. Herivel, ‘Aspects of French theoretical physics in the nineteenth century’, Brit. jour. hist. sci., 3 (1966), 109–132; and ‘The influence of Fourier on British mathematics’, Centaurus, 17 (1972), 40–57.
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• Kargon . 1969 . Model and analogy in Victorian science: Maxwell's critique of the French physicists . Jour. hist. ideas , 30 : 432 – 432 . A. F. Chalmers, however, has argued that Maxwell believed models to have no ontological status, but only heuristic value; see his ‘Maxwell's methodology and his application of it to electromagnetism’, Stud. hist. phil. sci., 4 (1973), 107–164.
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• Maxwell Ether The scientific papers of James Clerk Maxwell Niven W.D. Dover New York 1965 2 137 143 2 vols. reprinted in Papers (footnote 9), vol. 2, 763–775 (p. 775). This point is also made by Chalmers ibid., 160–161n.
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• Thomson , J.J. 1888 . Applications of dynamics to physics and chemistry , 8 – 8 . London : Macmillan .
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• Thomson , J.J. 1888 . Applications of dynamics to physics and chemistry , v – vi . London : Macmillan .
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• Thomson , J.J. 1888 . Applications of dynamics to physics and chemistry , 5 – 5 . London : Macmillan .
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• Thomson , J.J. 1888 . Applications of dynamics to physics and chemistry , 8 – 8 . London : Macmillan .
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• Thomson , J.J. 1888 . Applications of dynamics to physics and chemistry , 15 – 15 . London : Macmillan . For a similar view on ‘force’ and potential energy, see S. Tolver Preston, ‘On method in causal research’, Phil. mag., (5) 9 (1880), 356–367, esp. p. 361.
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• Thomson , J.J. 1888 . Applications of dynamics to physics and chemistry , 15 – 15 . London : Macmillan .
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• There is further evidence to support the argument that Thomson developed an interest in the philosophy of science. In a letter to Thomson, dated 23 September 1917, James Ward provided a list of several philosophical writings on science (for example Mach's Science of mechanics, Pearson's Grammar of science, and the writings of Poincaré and Stallo), and from the tone of the letter it may be inferred that Thomson had requested Ward to recommend such writings, specifically those which expounded a viewpoint similar to Thomson's idea that a ‘theory is a policy not a creed’. Since the works recommended by Ward were mainly positivistic—a methodology opposed by Thomson—it is interesting to imagine Thomson's reaction to these writings, if indeed he ever read them. One thing, however, is certain: there was no shift in Thomson's philosophical position after 1917; so even if he read them, these writings did not change his philosophical attitude. The letter is deposited in the archives of the University Library, Cambridge, Add. 7654, Box iii: W10. For permission to use this letter (and other material, quoted below), I should like to thank the University Librarian. On Thomson's friendship with Ward see Thomson J.J. Recollections and reflections Macmillan New York 1937 300 302 My use, in this discussion of Thomson's philosophy of science, of passage from his writings in the 20th century is justified, I believe, by the continuity in Thomson's thinking on philosophical matters.
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• In addition to the philosophical discussions cited below, see Thomson's On the vibrations of a vortex ring and the action upon each other of two vortices in a perfect fluid Phil. trans. Roy. Soc. London 1882 173 493 521 esp. pp. 493–494; ‘Chemical equilibrium’, in Watts' dictionary of chemistry (eds. M. M. P. Muir and H. F. Morley: 2nd. ed., 4 vols., 1888–1894, London), vol. 2 (1889), 434–446, esp. pp. 435 and 442; A treatise on the motion of vortex rings (London, Macmillan, 1883), 1; Recent researches (footnote 10), preface; and ‘James Clerk Maxwell’, in James Clerk Maxwell: A commemoration volume, 1831–1931 (Cambridge, 1931), 1–44.
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• Heimann . 1970 . Maxwell and the modes of consistent representation . Archive hist. exact sci. , 6 : 171 – 213 . passim.
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• As Thomson, of course, was well aware, Maxwell A treatise on electricity and magnetism , 3rd ed. 1891 2 480 493 in the last chapter of his had discussed various continental theories of ‘action at a distance’ (for example, those of Amp`ere, Gauss, Weber, Fechner, Helmholtz, Neumann and Clausius), and criticized them for not providing a ‘medium’ for the propagation of forces. Thomson made the same critique of the continental theories in his ‘Report on electrical theories’, B.A.A.S. Report, (1885), 97–155. Thomson, needless to say, concludes that Maxwell's theory is the best.
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• See Hesse M. Models and analogies in science Notre Dame 1966 passim; Forces and fields (New Jersey, Littlefield, Adams, and Co., 1965), chapter 1; and ‘Models in physics’, Brit. jour. phil. sci., 4 (1953), 198–214. Also see W. H. Leatherdale, The role of analogy, model, and metaphor in science (New York, American Elsevier, 1974), 41, 48, 52 and 79.
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• The formalized system for scientific theories was put forward by Duhem Pierre The aim and structure of physical theory Atheneum New York 1974 see his (trans. from the second edition of 1914 by P. P. Wiener This view was challenged by Norman R. Campbell in Physics: the elements (1920), reprinted as The foundations of science (New York, Dover, 1957). Campbell was a student of Thomson at Cambridge, and although Thomson has often been cited as ‘influencing’ Campbell's philosophy of models, no one has yet provided an in depth study of this possible influence. See, for example, J. Nicholas, “Norman Campbell”, Dictionary of scientific biography, vol. 3 (New York, 1971), 31-35; and G. Buchdahl, ‘Norman R. Campbell’, The encyclopedia of philosophy, vol. 2 (New York, Macmillan, 1967) 13–15. The present discussion of Thomson's philosophy of science is thus a first step toward such a study. For Campbell's views on the ether, see S. Goldberg, ‘In defense of ether: the British response to Einstein's special theory of relativity, 1905–1911’, Hist. stud. phys. sci., 2 (1970), 89–125 (pp. 117–121). For conflicting opinions on the similarities and differences between Duhem and Campbell, see Hesse, Models (footnote 31), Chapter 1; and D. H. Mellor, ‘Models and analogies in science: Duhem versus Campbell?’, Isis, 59 (1968), 282–290.
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• Thomson , J.J. Notebook # 160 (footnote 30).
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• Thomson , J.J. Notebook # 160 (footnote 30)
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• Leatherdale . 1974 . The role of analogy, model, and metaphor in science , 66 – 66 . New york : American Elsevier .
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• For a summary of this dispute, see Leatherdale The role of analogy, model, and metaphor in science American Elsevier New York 1974 46 47
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• Silliman , R.H. 1963 . William Thomson: smoke rings and nineteenth-century atomism . Isis , 54 : 461 – 474 . B. G. Doran, ‘Origins and consolidations of field theory in nineteenth century Britain: from the mechanical to the electromagnetic view of nature,’ Hist. stud. phys, sci., 6 (1975), 133–260; O. Knudsen, ‘From Lord Kelvin's notebook: ether speculations’, Centaurus, 16 (1971), 41–53; H. I. Sharlin, ‘William Thomson's dynamical theory: an insight into a scientist's thinking’, Annals of science, 32 (1975), 133–147; and C. Truesdell, Essays in the history of mechanics (Berlin, Springer-Verlag, 1968), 340–344.
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• Thomson , J.J. 1880 . On Maxwell's theory of light . Phil. mag. , 9 ( 5 ) : 284 – 291 . Thomson's paper, and its place in the context of the ‘ether problem’, is discussed in two papers by T. Hirosige, ‘Origins of Lorentz's theory of electrons and the concept of the electromagnetic field’, Hist. stud. phys. sci., 1 (1969), 151–209 (pp. 202–203); and ‘The ether problem, the mechanistic worldview, and the origins of the theory of relatively’, ibid., 7 (1976), 3–82 (pp. 23–24).
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• Thomson , J.J. 1881 . On the electric and magnetic effects produced by the motion of electrified bodies . Phil. mag. , 11 ( 5 ) : 229 – 249 . Thomson's derivation was modified by Oliver Heaviside, ‘On the electromagnetic effects due to the motion of electrification through a dielectric’, Phil. mag., (5) 27 (1889), 324–339, and G. F. C. Seale, ‘On the steady motion of an electrified ellipsoid’, Phil. mag., (5) 44 (1897), 329–341. For discussions of this work, see E. Whittaker, A history of the theories of aether and electricity (2 vols., rev. ed. 1951, Edinburgh, Nelson; repr. New York, Harper, 1960) vol. 1, 306–310; A. O'Rahilly, Electromagnetics (2 vols.: repr. Dover, New York, 1965), vol. 1, 235–241: M. Jammer, Concepts of mass (Cambridge, Mass., 1961), 136–141; and Doren (footnote 37), 224–225.
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• Thomson . 1881 . On the electric and magnetic effects produced by the motion of electrified bodies . Phil. mag. , 11 ( 5 ) : 230 – 230 . Oliver Lodge once referred to Thomson's 1881 paper as ‘an epoch-making paper … one of the most remarkable memoirs of our time’ (Electrons: or the nature and properties of negative electricity (London, 1906), 17).
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• In addition to Hirosige Origins of Lorentz's theory of electrons and the concept of the electromagnetic field Hist. stud. phys. sci. 1969 1 151 209 see L. S. Swenson jr., The ethereal aether (Austin, 1972).
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• Thomson . 1889 . On the magnetic effects produced by motion in the electric field . Phil. mag. , 28 ( 15 ) : 1 – 14 . In this paper, Thomson used an equation of George Stokes from his paper ‘On the effects of the internal friction of fluids on the motion of pendulums’, where Stokes determined the motion of a fluid around a moving sphere. This paper is reprinted in George Stokes, Mathematical and physical papers (5 vols.: 1880–1905, Cambridge, University Press; repr. New York, Johnson, 1966), vol. 3, 1–142; see esp. pp. 55–67. For a modern derivation of the kinetic energy outside a moving sphere, see D. E. Rutherford, Fluid dynamics (London, Oliver and Boyd, 1959), 103. On Stokes, see D. B. Wilson, ‘George Gabriel Stokes on Stellar aberration and the luminiferous ether,’ Brit. jour. hist. sci., 6 (1972), 57–72.
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• See Knudsen O. The Faraday effect and physical theory, 1845–1873 Archive hist. exact sci. 1976 15 235 281 and J. B. Spencer, ‘On the varieties of 19th-century magneto-optical discovery’, Isis, 61 (1970), 34–51. On Maxwell, see especially Knudsen, 248–255.
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• Thomson . 1885 . Note on the rotation of the plane of polarization of light by a moving medium . Proc. Camb. Phil. Soc. , 5 : 250 – 254 .
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• von Helmholtz , Hermann . 1868 . On integrals of the hydrodynamical equations, which express vortexmotion . Phil. mag. , 33 ( 4 ) : 484 – 511 . This paper was translated from the original German article of 1858 by P. G. Tait. William Thomson (Lord Kelvin), ‘On vortex atoms’ (1868), reprinted in William Thomson, Mathematical and physical papers (6 vols., Cambridge, University Press, 1882–1911), vol. 4, 112. See also Silliman (footnote 37); Whittaker (footnote 39), vol. 1, 293–303; Doran (footnote 37), 129–207; and D. M. Knight, Atoms and elements (London, Hutchinson, 1970), 70–74. Also of interest is the article by David B. Wilson, ‘Kelvin's scientific realism: the theological context’, The philosophical journal: transactions of the Royal Philosophical Society of Glasgow, 11 (1974), 41–60.
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• Thomson , J.J. 1879 . Vortex motion in a viscous incompressible fluid . Mess. math. , 8 : 174 – 181 . and ‘On the vibrations of a vortex ring and the action upon each other of two vortices in a perfect fluid’, Phil. trans. Roy. Soc. London, 173 (1882), 493–521.
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• Thomson , J.J. 1883 . A treatise on the motion of vortex rings , London : Macmillan .
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• Thomson J.J. A treatise on the motion of vortex rings Macmillan London 1883 1 1 (italics mine) Thomson also used the phrase ‘of a much more fundamental character’ in ‘On the vibrations’ (footnote 46), 494.
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• Maxwell put it this way: ‘But the greatest recommendation of this [vortex] theory, from a philosophical point of view, is that its success in explaining phenomena does not depend on the ingenuity with which its contrivers “save appearances”, by introducing first one hypothetical force and then another’ (‘Atom’, reprinted in The scientific papers of James Clerk Maxwell Niven W.D. Dover New York 1965 2 445 484 2 vols. (p. 471)).
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• Heilbron , J. 1971 . “ Joseph John Thomson ” . In Dictionary of scientific biography Vol. 3 , 362 – 372 . New York (pp. 362–363). In the terminology of Buchdahl, Thomson was appealing to an ‘architectonic’ criterion for the defence of a scientific hypothesis (see Gerd Buchdahl, ‘History of science and criteria of choice’, Historical and philosophical perspectives of science (ed. R. Stuewer: Minneapolis, 1970), 204–230). Near the end of his life, in his autobiography (Recollection (footnote 26), 94–95) Thomson recalled the vortex theory as being ‘a theory more fundamental and definite than any that had been advanced before. There was a spartan simplicity about it’.
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• Thomson , J.J. 1883 . On a theory of the electric discharge in gases . Phil. mag. , 15 ( 5 ) : 427 – 434 . ‘On the chemical combination of gases’, Phil. mag., (5) 18 (1884), 233–267; ‘The vortex theory of gases; on the law of the distribution of energy among the molecules,’ Proc. Roy. Soc. London, 39 (1885) 23–36; and ‘Some experiments on the electric discharge in a uniform electric field, with some theoretical considerations about the passage of electricity through gases’, Proc. Camb. Phil. Soc., 5 (1886), 391–409. See also Whittaker (footnote 39), vol. 1, 294n.
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• See, for example Heilbron Joseph John Thomson Dictionary of scientific biography New York 1971 3 362 372 esp. p. 368. It is also interesting to note that Thomson's 1881 paper ‘On the electric and magnetic effects’ (footnote 39) began by referring to the recent cathode-ray experiments, and that he conceived of his paper as providing a theoretical ‘basis’ for such experiments (p. 229). See also Thomson's paper, ‘The relation between the atom and the charge of electricity carried by it,’ Phil. mag., (5) 40 (1895), 511–544, where he used the vortex picture as an ‘illustration’ or ‘analogy’.
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• This letter, dated 20 June 1898, was written to Silas Holman of the Massachusetts Institute of Technology, and is quoted in Holman's book Matter, energy, force and work Macmillan New York 1898 226 226 I was led to this reference by Silliman (footnote 37).
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• On Kelvin, see Doran Origins and consolidations of field theory in nineteenth century Britain: from the mechanical to the electromagnetic view of nature Hist. stud. phys, sci. 1975 6 218 218 and Whittaker (footnote 39), vol. 1, 303. See also Joseph Larmor, ‘Report on mathematical and physical science,’ B.A.A.S. report, (1900), 613–628 (p. 625).
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• Thomson , J.J. 1883 . A treatise on the motion of vortex rings , xi – xi . London : Macmillan . and 13
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• Thomson , J.J. 1937 . Recollections and reflections , 94 – 95 . New York : Macmillan .
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• Thomson , J.J. 1907 . The corpuscular theory of matter 1 – 1 . New York The full context of this statement bears quoting (pp. 1–2): ‘From the point of view of a physicist, a theory of matter is a policy rather than a creed; its object is to connect or coordinate apparently diverse phenomena, and above all to suggest, stimulate, and direct experiment’. The former ‘object’ of a theory, in the context of Thomson's work in physics, is (of course) the focal point of this study.
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• Thomson , J.J. 1893 . Notes on recent researches in electricity and magnetism , 1 – 1 . Oxford : Clarendon .
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• Thomson , J.J. 1885 . Report on electrical theories . B.A.A.S. Report , : 97 – 155 . (p. 126).
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• Thomson , J.J. 1891 . On the illustration of the properties of the electric field by means of tubes of electrostatic induction . Phil. mag. , 31 ( 5 ) : 149 – 171 .
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• See Thomson's preface to the third edition of Maxwell's A treatise on electricity and magnetism , 3rd ed. 1891 1 xv xvi 2 vols.
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• Thomson , J.J. 1909 . Presidential address . B.A.A.S. report , : 3 – 29 . (p. 29).
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• Thomson , J.J. 1893 . Notes on recent researches in electricity and magnetism , vi – vi . Oxford : Clarendon .
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• Thomson , J.J. 1893 . Notes on recent researches in electricity and magnetism , v – v . Oxford : Clarendon .
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• Thomson , J.J. 1893 . Notes on recent researches in electricity and magnetism , vi – vi . Oxford : Clarendon .
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• Thomson , J.J. 1893 . Notes on recent researches in electricity and magnetism , vi – vi . Oxford : Clarendon .
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• Thomson , J.J. 1893 . Notes on recent researches in electricity and magnetism , vii – vii . Oxford : Clarendon .
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• Thomson , J.J. 1893 . Notes on recent researches in electricity and magnetism , vii – vii . Oxford : Clarendon .
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• See, for example Feyerabend P. Against method New Left Books London 1975
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• Thomson . 1893 . Notes on recent researches in electricity and magnetism , vii – vii . Oxford : Clarendon .
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• Thomson . 1893 . Notes on recent researches in electricity and magnetism , 3 – 3 . Oxford : Clarendon .
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• Thomson . 1893 . Notes on recent researches in electricity and magnetism , 1 – 1 . Oxford : Clarendon . see footnote 10 above.
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• The derivation is contained in Thomson Notes on recent researches in electricity and magnetism Clarendon Oxford 1893 7 16
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• The derivation is contained in Thomson Notes on recent researches in electricity and magnetism Clarendon Oxford 1893 16 23
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• The derivation is contained in Thomson Notes on recent researches in electricity and magnetism Clarendon Oxford 1893 16 16
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• The derivation is contained in Thomson Notes on recent researches in electricity and magnetism Clarendon Oxford 1893 4 5
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• The derivation is contained in Thomson Notes on recent researches in electricity and magnetism Clarendon Oxford 1893 3 4
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• The derivation is contained in Thomson Notes on recent researches in electricity and magnetism Clarendon Oxford 1893 52 52
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• Price D.J. Thomson J.J. Nuovo cimento 1956 4 1609 1629 (supplemento) (p. 1615).
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• On Thomson's discovery of the electron, see: Heilbron Joseph John Thomson Dictionary of scientific biography New York 1971 3 362 372 Price ibid.; Lord Rayleigh, The life of Sir J. J. Thomson (repr. Dawsons, London, 1969); George Thomson, J. J. Thomson, discoverer of the electron (New York, Doubleday, 1966); D. L. Anderson, The discovery of the electron (Princeton, New Jersey; D. Van Nostrand, 1964); G. E. Owen, ‘The discovery of the electron’, Annals of science, 11 (1955), 173–182; and B. A. Morrow, ‘On the discovery of the electron’, Jour. chem. ed., 46 (1969), 584–588. For historical accuracy, I recommend Heilbron's discussion.
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• There were four major lectures: (1) delivered at Yale University in May 1903, and published as a book Electricity and matter Charles Scribner's Sons New York 1904 (2) delivered as a series of lectures at the Royal Institution in the Spring of 1906, and published as Corpuscular (footnote 57); (3) delivered as the Adamson Lecture at Victoria University, Manchester, on 4 November 1907, and published as ‘Light’ (1908) (footnote 2); and (4) ‘Presidential address’ (1909) (footnote 63).
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• For a discussion of this British tradition in the late 19th and early 20th century, and Thomson's place in it, see Goldberg In defense of ether: the British response to Einstein's special theory of relativity, 1905–1911 Hist. stud. phys. sci. 1970 2 89 125
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• Thomson . 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 233 – 233 .
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• Thomson . 1909 . Presidential address . B.A.A.S. report , : 15 – 15 . On Newton's metaphor, see A. Thackray, ‘“Matter in a nut-shell”: Newton's Opticks and 18th-century chemistry’, Ambix, 15 (1968), 29–53.
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• Thomson . 1909 . Presidential address . B.A.A.S. report , : 15 – 16 . Compare O'Rahilly (footnote 39), 2, chapter 13.
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• Wilson , D.B. 1971 . The thought of late victorian physicists: Oliver Lodge's etheral body . Victorian studies , 15 : 29 – 48 . As late as 1928(!), Lodge wrote to Thomson: ‘The beginning of a universal ether theory seems to be looming close upon us’. The letter is deposited in the archives of the University Library, Cambridge, Add. 7654, Box ii: L 52.
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• Larmor . 1900 . Aether and matter quoted in Goldberg (footnote 32), 106. On Larmor see Doran (footnote 37), passim. The thrust of Doran's lengthy article is that by the 20th century most British physicists had both dematerialized and demechanized the ether. But, as she also points out, Thomson was an exception here (see, for example, p. 161, footnote 71 of her article).
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• Thomson refereed (and recommended for publication) the first and third parts of Larmor's paper, A dynamical theory of the electric and luminiferous medium Phil. trans. Roy. Soc. London 1894 185 719 822 186 (1895), 695–743, 190 (1898), 205–300. The reports are deposited in The Royal Society, R.R., vol. 12 (#160), and vol. 13 (#207). For permission to quote from these reports I should like to thank the Librarian of The Royal Society.
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• Kaufmann , Walter . 1901 . Die magnetische und elektrische ablenkbarkeit der Becqueralstrahlen und die scheinbare masse der electronen . Göttinger Nachrichten , : 143 – 155 . and ‘Über die elektromagnetische masse des elektrons,’ ibid. (1902), 291–296. See also Jammer (footnote 39), 136–141; and Hirosige, ‘The ether problem’ (footnote 38), 51, 74, 75.
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• Thomson . 1904 . Electricity and matter , 51 – 51 . New York : Charles Scribner's Sons . Oliver Lodge's enthusiasm for Thomson's idea is clear from the title bestowed upon his review of Thomson's book, Electricity and matter: ‘Steps toward a new Principia’, Nature, 70 (1904), 73–76.
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• Thomson . 1904 . Electricity and matter , 51 – 51 . New York : Charles Scribner's Sons . Compare Corpuscular (footnote 57), 28–34. See also Doran (footnote 37), 161–162n.
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• The tube picture was used in Electricity 1904 but in both Corpuscular (1907) and ‘Light’ (1908) he used lines of forces (see footnote 82). But in 1910 he returned to the tubes picture in ‘On a theory of the structure of the electric field and its application to Röntgen radiation and to light,’ Phil. mag., (6) 19 (1910), 301–313; and in 1914 in ‘The forces between atoms and chemical affinity’, Phil. mag., (6) 27 (1914), 757–789. Thereafter, Thomson usually used only the lines of force picture.
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• Thomson . 1970 . The corpuscular theory of matter 2 – 2 . New York In 1931, for example, Thomson attempted to derive Schrödinger's equation for quantum physics from a vortex equation (see ‘On the analogy between the electromagnetic field and a fluid containing a large number of vortex filaments’, Phil. mag., (7) 12 (1931), 1057–1063).
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• Thomson . 1970 . The corpuscular theory of matter 2 – 2 . New York Maxwell also noted the mathematical difficulties in his article ‘Atom’, in Papers (footnote 9), vol. 2, 445–484 (p. 472).
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• Duhem The aim and structure of physical theory Atheneum New York 1974 318 318 (trans. from the second edition of 1914 by P. P. Wiener E. Meyerson, Identity and reality (trans. of 3rd. ed. (1926) by K. Loewenberg: New York, Dover, 1962), 978; O. W. Richardson, The electron theory of matter (2nd. ed., Cambridge, 1916), 229; and F. Cajori, A history of physics (1929: repr. Dover, New York, 1962), 360.
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• Thomson . 1907 . The corpuscular theory of matter 28 – 28 . New York
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• Thomson . 1909 . Presidential address . B.A.A.S. report , : 12 – 12 .
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• Frank Philipp Modern science and its philosophy Collier New York 1941 158 158 repr. 1961
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• For recent discussions of this electrical theory of matter see Jammer Concepts of mass Cambridge, Mass. ‘The electromagnetic theory of mass,’ 136–153; R. McCormmach, ‘H. A. Lorentz and the electromagnetic view of nature’, Isis, 61 (1970), 459–497; Doran (footnote 37), passim; T. J. Trenn, The self-splitting atom: the history of the Rutherford-Soddy collaboration (London, Taylor & Francis, 1977), passim; and D. M. Siegel, ‘Classical-electromagnetic and relativistic approaches to the problem of non integral atomic masses’, Hist. stud. phys. sci., 9 (1977), 323–360.
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• Thomson . 1909 . Presidential address . B.A.A.S. report , : 17 – 17 .
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• Thomson . 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 235 – 235 .
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• 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 235 – 235 . Compare P. M. Heimann, ‘The unseen universe: physics and the philosophy of nature in Victorian Britain’, Brit. jour. hist. sci., 6 (1972), 73–79; and D. B. Wilson (footnote 87).
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• Thomson . 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 241 – 242 .
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• 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 243 – 243 . Compare his (footnote 63), 19–20.
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• 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 244 – 244 .
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• 1908 . On the light thrown by recent investigations on electricity on the relation between matter and ether . Annual report of the Smithsonian Institution , : 244 – 244 . Thomson expressed the same idea in (footnote 63), 18–20. For the rationale for my insert ‘as yet’, see footnote 128.
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• Aronson , S. 1964 . The gravitational theory of George Louis Le Sage . The natural philosopher , 3 : 53 – 74 . and Doren (footnote 37), 192–4.
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• Kelvin On the ultramundane corpuscles of Le Sage Mathematical and physical papers Thomson William Cambridge1882–1911 5 64 76 (1871), in (6 vols.,
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• Tait , P.G. 1876 . Lectures on some recent advances in physical science (with a special lecture on force) , 2nd rev. ed. 362 – 362 . London
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• Maxwell . 1965 . The scientific papers of James Clerk Maxwell , Edited by: Niven , W.D. Vol. 2 , 473 – 476 . New York : Dover . 2 vols.
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• See Preston On method in causal research Phil. mag. 1880 9 5 356 367 his ‘On some dynamical conditions applicable to Le Sage's theory of gravitation’, Phil. mag., (5) 4 (1877), 206–213, 364–375; Oliver Lodge, ‘The ether and its function’, Nature, 27 (1883), 304–306, 328–330; Preston's letter to the editor. ‘The ether and its function’, Nature, 27 (1883), 579; and Doran (footnote 37), 192–194.
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• Thomson . 1893 . Notes on recent researches in electricity and magnetism , 15 – 15 . Oxford : Clarendon .
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• Thomson . 1904 . Electricity and matter , 158 – 162 . New York : Charles Scribner's Sons . Thomson was certainly aware of Preston, for they corresponded in the spring and summer of 1893. The correspondence was initiated by Preston, who sent Thomson a draft of a manuscript in which Preston attempted to explain psychic phenomena by assuming that electromagnetic waves are produced by the human brain. The manuscript, ‘On the physics of thought-reading’, and five letters to Thomson are deposited in the archives of the University Library, Cambridge, Add. 7654, Box ii: P45–49. I have not, however, been able to locate Thomson's replies to Preston.
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• For this involvement, see Thomson George J. J. Thomson, discoverer of the electron Doubleday New York 1966 Chapter 10; and Rayleigh (footnote 81), chapter 10.
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 679 – 689 .
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 679 – 679 .
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 679 – 679 .
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 680 – 680 . For a critique of this see, O'Rahilly (footnote 39), vol. 1, 240–241.
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 680 – 680 . This physical conception was based upon a calculation presented in Electricity (footnote 82), 36–38. There he showed that for a moving electron, from which Faraday Tubes protrude radially, the electrostatic energy (per unit volume) is equal to the kinetic energy of the mass of ether carried by the tubes, this mass moving with the velocity of light.
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 680 – 680 .
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 683 – 683 .
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 683 – 683 .
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• Thomson , J.J. 1920 . Mass, energy and radiation . Phil. Mag. , 39 ( 7 ) : 684 – 685 . As well, Thomson made a rough calculation, and determined that there are approximately 1010 mass particles in one electron (p. 689).
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• Thomson , J.J. 1930–31 . Atoms and electrons . Manchester memoirs , 75 : 77 – 93 . (p. 87).
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• In his National Broadcast Lecture of 24 January 1930, ‘Tendencies of recent investigations in the field of physics,’ Thomson asserted: There is now a school of mathematical Physicists which objects to the introduction of ideas which do not relate to things which can actually be observed and measured… I believe that this view now gets no support from metaphysicians. I think it is bad Physics as well as bad Metaphysics. I hold that if the introduction of a quantity promotes clearance of thought; then even if at the moment we have no means of determining it with precision, its introduction is not only legitimate but desirable. The immeasurable of to-day may be the measurable of tomorrow. This passage is quoted in Rayleigh The life of Sir J. J. Thomson Dawsons London 1969 265 265 (repr. I think it is safe to say that Thomson had in mind here the, as of yet, ‘immeasurable’ granules.
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• This is not to deny the fact that Thomson often used various force laws between entities in his physical models. See, for example On the structure of the atom Phil. mag. 1913 26 6 792 799 ‘On the origin of spectra and Planck's law’, Phil. mag., (6) 37 (1919), 419–446; and The electron in chemistry (Philadelphia, 1923). But still, Thomson's ultimate quest was for a mechanical explanation of these forces.
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• Arnheim , Compare R. 1969 . Visual thinking London
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