The Reception of Miller's Ether-Drift Experiments in the USA: The History of a Controversy in Relativity Revolution

Summary

This paper analyses documents from several US archives in order to examine the controversy that raged within the US scientific community over Dayton C. Miller's ether-drift experiments. In 1925, Miller announced that his repetitions of the famous Michelson-Morley experiment had shown a slight but positive result: an ether-drift of about 10 kilometres per second. Miller's discovery triggered a long debate in the US scientific community about the validity of Einstein's relativity theories. Between 1926 and 1930 some researchers repeated the Michelson-Morley experiment, but no one found the same effect as Miller had. The inability to confirm Miller's result, paired with the fact that no other ether theory existed that could compete with special relativity theory, made his result an enigmatic one. It thus remained of little interest to the scientific community until 1954, when Robert S. Shankland and three colleagues reanalysed the data and proposed that Miller's periodic fringe shift could be attributed to temperature effects. Whereas most of the scientific community readily accepted this explanation as the conclusion of the matter, some contemporary anti-relativists have contested Shankland's methodology up to now. The historical accounts of Miller's experiments provide contradictory reports of the reaction of the US scientific community and do not analyse the mechanisms of the controversy. I will address this shortcoming with an examination of private correspondence of several actors involved in these experiments between 1921 and 1955. A complex interconnection of epistemic elements, sociological factors, and personal interests played a fundamental role in the closure of this experimental controversy in the early 1930s, as well as in the reception of Shankland's reanalysis in the 1950s.

Acknowledgements

My research was realized thanks to financial support of the Università degli Studi di Milano, Dottorato in Storia Internazionale, and the Center for History of Physics, American Institute of Physics. My first thanks are for my Ph.D. supervisor Prof. Pasquale Tucci (Università degli Studi di Milano) who has given me all his personal and institutional support, and Dr. Gregory Good and Dr. Joseph Anderson (Center for History of Physics/American Institute of Physics) who supported my research in the US archives. This paper could never be made without the help of Prof. John Stachel (Boston University), Prof. William Fickinger (Case Western Institute), and Dr. Leonardo Gariboldi (Università degli Studi di Milano). I am deeply indebted to Dr. Daniela Famulari (Centre for Ecology and Hydrology) for improving my English and the doctorate candidate Alma Steingart (HASTS program, MIT) for the last editing. The last version of this paper owes much to the suggestions of the unknown referees and of the editors of Annals of Science. I also thank Prof. David Kaiser (STS Program, MIT) for his suggestions and the staffs of all the archives I quote in the footnotes for the invaluable help and the permission to publish their materials, in particular the Albert Einstein Archive (Hebrew University of Jerusalem), Prof. Diana K. Buchwald and Dr. Ze'ev Rosenkranz of the Einstein Paper Project (Caltech), the Niels Bohr Archive and Library (American Institute of Physics), the CWRU Archives (Cleveland), the USNA Nimitz Library, Special Collection and Archives Division (Annapolis), the Caltech Archives (Pasadena), the Huntington Library (Pasadena), and the Department of Special Collections, University of St. Thomas (St. Paul, MN).

Notes

¹L. S. Swenson Jr., The Ethereal Ether: A History of the Michelson-Morley Aether-Drift Experiments, 1880–1930 (Austin/London, 1972). Miller's most quoted and comprehensive paper is D. C. Miller, ‘The Ether-Drift Experiment and the Determination of the Absolute Motion of the Earth’, Reviews of Modern Physics, 5 (1933), 203–42. This paper is an invaluable historical source because in it, Miller thoroughly described all his ether-drift experiments between 1902 and 1926. Swenson used this paper as the primary source for his historical analysis of Miller's experiments. This choice led Swenson to sometimes accept Miller's account without a critical analysis of the persuasive rhetoric Miller used in his arguments.

²Arguments in favour of a non-null result are, e.g., in J. P. Vigier, ‘Relativistic Interpretation (with non-zero photon mass) of the small ether drift velocity detected by Michelson, Morley, and Miller’, Apeiron, 4 (1997), 71–76; F. Selleri, ‘On the Anisotropy Observed by Miller and Kennedy & Thorndike’, in Recent Advances in Relativity Theory 2: Material Interpretations, edited by M. Duffy and M. Wegener, (Palm Harbor, 2000), 281–83; H. A. Munera, ‘Michelson-Morley Experiments Revisited: Systematic Errors, Consistency among Different Experiments, and Compatibility with Absolute Space’, Apeiron, 5 (1998), 37–53; M. Allais, ‘Des régularités très significatives dans les observations interférométriques de Dayton C. Miller 1925–1926’, Comptes Rendus de L'Académie des Sciences, 327 (1999), 1405–10; and M. Consoli and E. Costanzo, ‘From classical to modern ether-drift experiments: The narrow window for a preferred frame’, Physics Letters A, 333 (2004), 355–63.

³For a complete bibliography and descriptions of the approaches of the sociology of science to controversy studies, see S. Sismondo, An Introduction to Science and Technology Studies (2^nd ed., Chichester, 2010), 120–35.

⁴This approach was, in part, based on David Bloor's tenet of impartiality, in particular with respect to the dichotomy rational/irrational. D. Bloor, Knowledge and Social Imagery (London, 1976).

⁵C. G. Darwin, ‘Logic and Probability in Physics’, Philosophy of Science, 6 (1939), 48–64 (51). Darwin's description was accepted by philosophers of science Michael Polanyi and Imre Lakatos, but with diametrically opposing judgements about the reasons the scientific community discarded the experimental result. Polanyi underlined the irrational strength of beliefs in the behaviour of the scientific community in M. Polanyi, The Logic of Liberty: Reflections and Rejoinders (London, 1951); and M. Polanyi, Personal Knowledge: Towards a Post-critical Philosophy (London, 1958); whereas Lakatos replied to Polanyi that ‘the tenacity of the Einsteinian research programme in the face of alleged contrary evidence [was] a completely rational phenomenon’. I. Lakatos, ‘Falsification and the methodology of scientific research programme’, in I. Lakatos and A. Musgrave (eds.) Criticism and the Growth of Knowledge (Cambridge, 1970), 91–195 (163).

⁶These were the repetition of the MMT experiment performed by Michelson himself and the experiment performed by the German theoretical physicist Georg Joos in Jena: A. A. Michelson, F. G. Pease and F. Pearson, ‘Repetition of the Michelson-Morley Experiment’, Journal of the Optical Society of America, 18 (1929), 181–82; and G. Joos ‘Die Jenaer Wiederholung des Michelsonversuchs’, Annalen der Physik, 7 (1930), 385–407. Swenson himself accepted that the controversy was closed thanks to the null result obtained by these two experiments, in particular, that of Michelson; see Swenson (note 1), 213–27.

⁷K. R. Popper, Logik der Forschung (Tübingen, 1934).

⁸See, e. g., W. K. H. Panofsky and M. Phillips, Classical Electricity and Magnetism (1st ed. Reading, MA, 1955; and 2nd ed. Reading, MA, 1962); R. G. W. Brown and E. R. Pike, ‘A History of Optical and Optoelectronic Physics in the Twentieth Century’, in L. M. Brown, A. Pais and Sir B. Pippard (eds.), Twentieth Century Physics, 3 vols. (Bath, 1995), III, 1385–1504; and M. A. Tonnelat, Histoire du Principe de Relativité (Paris, 1971). Also the influential historians of science Gerald Holton and Lewis Pyenson accepted that Shankland found the real explanation for the effect. G. Holton, ‘Einstein, Michelson and the ‘crucial’ experiment’, in G. Holton, Thematic Origins of Scientific Thoughts (2^nd ed., Cambridge, MA, 1988), 279–370; and B. Haubold, H. J. Haubold and L. Pyenson, ‘Michelson's First Ether-Drift Experiment in Berlin and Potsdam’, in S. Goldberg and R. H. Stuewer (eds.), The Michelson Era in American Science 1870–1930 (New York, 1988). The Case School of Applied Science was renamed Case Institute of Technology in 1948, but in this paper I refer to it as ‘Case’. In 1967 Case combined with the nearby Western Reserve University to form the Case Western Reserve University (CWRU).

⁹E. E. Slosson to A. Einstein, 26 June 1925, Pasadena, CA, Einstein Papers Project, Albert Einstein Archives (AEA) 17–259, courtesy Hebrew University of Jerusalem.

¹⁰Holton (note 8), 293.

¹¹P. Galison, How Experiments End (Chicago, 1987), 6. For a bibliography of philosophical writings on the possibility of experimental autonomy from theoretical expectations, see ibid., 6–13.

¹²See S. Goldberg, Understanding Relativity (Oxford, 1984); and T. F. Glick (ed.), The Comparative Reception of Relativity (Boston, 1987). These books compare the national differences in the reception of relativity. The historian of science Stephen G. Brush also used national statistical differences in his general analysis of the acceptance of relativity. S. G. Brush, ‘Why Was Relativity Accepted?’, Physics in Perspective, 1 (1999), 184–214. For a criticism of the use of national boundaries as the units of analysis in reception studies, see A. Warwick, ‘Cambridge Mathematics and Cavendish Physics: Cunningham, Campbell and Einstein's Relativity 1905–1911; Part I: The Uses of Theory’, Studies in History and Philosophy of Science, 24 (1992), 625–56, in particular pp. 625–34.

¹³A similar approach to the controversy about Miller's result was already used in J. Crelinsten, Einstein's Jury: The Race to Test Relativity (Princeton/Oxford, 2006).

¹⁴R. S. Shankland, S. W. McCuskey, F. C. Leone and G. Kuerti, ‘New Analysis of the Interferometer Observations of Dayton C. Miller’, Reviews of Modern Physics, 27 (1955), 167–78.

¹⁵Klaus Hentschel wrote an account of these events based on several archival documents. K. Hentschel, ‘Einstein's Attitude towards Experiments: Testing Relativity Theory 1907–1927’, Studies in History and Philosophy of Science, 23 (1992), 593–624. The topic of Einstein's attitude towards experiments and the connected issue of the relevance of the MM experiment in the development of special relativity theory were studied by several historians and philosophers of science and initiated a controversy. Holton's description of the ‘Philosophical Pilgrimage of Albert Einstein’ from an earlier empiricism towards rational realism (G. Holton, ‘Mach, Einstein and the Search for Reality’, in Holton [note 8], 237–77) was challenged in, e.g., P. Feyerabend, Against Method: Outline of an Anarchistic Theory of Knowledge (London, 1975); and J. Shelton, ‘The Role of Observation and Simplicity in Einstein's Epistemology’, Studies in History and Philosophy of Science, 19 (1988), 103–18.

¹⁶The claim that Shankland's paper does not resolve the issue is not a prerogative of anti-relativist dissident scientists. A new analysis of Miller's data was performed in T. J. Roberts, ‘An Explanation of Dayton Miller's Anomalous “Ether Drift” Result’, arXiv:physics/0608238v3. In this paper, Roberts shows that Miller made mistakes in error analysis. In this way, the author found a solution in complete agreement with special relativity theory without confirming Shankland's analysis.

¹⁷For an epistemological analysis of the meaning of the repetition of experiment, see R. Laymon, ‘Independent Testability: The Michelson-Morley and Kennedy-Thorndike Experiments’, Philosophy of Science, 47 (1980), 1–37.

¹⁸It is important to underline here that the scholar who began to study this topic from a historical perspective was Shankland himself. R. S. Shankland, ‘Michelson at Case’, American Journal of Physics, 17 (1949), 487–90; and ‘The Michelson-Morley Experiment’, American Journal of Physics, 31 (1964), 16–35. The most exhaustive narrative history is Swenson (note 1). Jed Z. Buchwald has argued that this experiment was at the margin of British and Continental scientific communities’ interest before 1900. J. Z. Buchwald, ‘The Michelson-Morley Experiment in the Light of Electromagnetic Theory Before 1900’, in Goldberg and Stuewer (eds.) (note 8), 55–70.

¹⁹It is sufficient here to remember the famous and influential debate between Holton and the philosopher of science Adolf Grünbaum. For the respective theses, see A. Grünbaum, ‘The Genesis of the Special Theory of Relativity’, in H. Feigl and G. Maxwell (eds.), Current Issues in the Philosophy of Science (New York, 1961), 43–53; and Holton (note 8); Holton's view that the MM had not a ‘genetic role’ in Einstein's creation of special relativity theory seems to be the most influential on contemporary historiography; see, e.g., A. I. Miller, Albert Einstein's Special Theory of Relativity: Emergency (1905) and early Interpretation (1905–1911) (Reading, 1981); and J. Stachel, ‘Einstein and Ether Drift Experiments’, Physics Today, 40 (1987), 45–47. On the other hand, the historian and philosopher of science Jeroen Van Dongen has recently found some arguments against this view. J. van Dongen, ‘On the role of the Michelson-Morley Experiment: Einstein in Chicago’, Archive for History of Exact Sciences, 63 (2009), 655–63.

²⁰Sometimes the MMT experiment is related to the second principle of special relativity theory: the light velocity's independence from the source's motion; see Swenson (note 1), 163. But John Stachel has underlined that Einstein referred to this experiment only in connection with the first postulate, namely the principle of relativity. J. Stachel, ‘Einstein and Michelson: The Context of Discovery and the Context of Justification’, in J. Stachel, Einstein from ‘B’ to ‘Z’ (Boston, 2002), 177–90.

²¹A. A. Michelson and E. W. Morley, ‘Relative Motion of the Earth and Luminiferous Ether’, American Journal of Science, 34 (1887), 333–45 (341).

²²Miller (note 1); and Swenson (note 1), 94.

²³E. W. Morley and D. C. Miller, ‘Report of an Experiment to Detect Change of Dimension of Matter Produced by its Drift through the Ether’, Science, 21 (1905), 339 [emphasis mine].

²⁴E. W. Morley and D. C. Miller, ‘Final Report on Ether-Drift Experiments’, Science, 25 (1907), 525.

²⁵Miller (note 1), 217; quoted also in Swenson (note 1), 153.

²⁶A. Einstein, ‘Zur Elektrodynamik bewegter Körper’, Annalen der Physik, 17 (1905), 891–921 (892).

²⁷A. S. Eddington, F. W. Dyson and C. Davidson, ‘A Determination of the Deflection of Light by the Sun's Gravitational Field, from Observations made at the Total Eclipse of May 29, 1919’, Philosophical Transactions of the Royal Society of London Series A, 220 (1920), 291–333.

²⁸See A. Pais, ‘Subtle is the Lord’: The Science and the Life of Albert Einstein (Oxford, 1982). For a study of the importance of newspapers in constructing Einstein's fame in the USA, see M. Missner, ‘Why Einstein Became Famous in America’, Social Studies in Science, 15 (1985), 267–91.

²⁹Miller (note 1), 217. Miller's student, Douglas L. Darnell, remembered that ‘[Miller] said that Einstein had based his theory on incomplete experimental data and that he would have to get busy and complete the aether-drift’. Darnell to Shankland, 10 April 1963, Cleveland, CWRU Archives, Robert S. Shankland Papers (RSP), A 08–19, box 1.

³⁰Swenson (note 1), 191. It is evident from these statements that Swenson generalized Miller's strong opinions as to whether they described objective facts.

³¹In April 1920, Miller went to Philadelphia to request Hale's help with the photos of the Morley-Miller interferometer. Miller to Hale, 11 November 1920; and Miller to Hale, 19 January 1921, College Park, MD, Niels Bohr Library and Archives of American Institute of Physics (AIP), Papers of George E. Hale (HP), roll 93. On the contrary, Swenson reported that Hale invited Miller. Swenson (note 1), 192; see also Crelinsten (note 13), 232.

³²Hale to Miller, 19 July 1920, AIP, HP, roll 93.

³³Miller's ether drift experiments were sponsored by Eckstein Case, treasurer of Case, who paid all the expenses. Miller (note 1), 217.

³⁴L. Silberstein, The Theory of Relativity (London, 1914).

³⁵Merritt to Hale, 22 November 1920, AIP, HP, roll 93.

³⁶L. Silberstein, The Theory of General Relativity and Gravitation (New York, 1922).

³⁷L. Silberstein, ‘The Recent Eclipse Results and Stokes-Planck's Aether’, Philosophical Magazine, (1920), 160–71. This little-known theory was made public by Lorentz in H. A. Lorentz, ‘Stokes' theory of aberration in the supposition of a variable density of the aether’, Verslagen Koninklijke Akademie van Wetenschappen 1, (1899), 443–48; and in the well-known H. A. Lorentz, The Theory of Electrons and Its Applications to the Phenomena of Light and Radiant Heat: A course of lectures delivered at Columbia University, New York, in March and April 1906 (Leipzig, 1909).

³⁸L. Silberstein, ‘The Propagation of Light in Rotating Systems’, Journal of the Optical Society of America, 5 (1921), 291–307. This experiment was already proposed by Michelson in A. A. Michelson, ‘Relative Motion of Earth and Ether’, Philosophical Magazine, 8 (1904), 717–19. It was realized by Michelson and Henry G. Gale of the University of Chicago in 1925. The result was in accord with the amount of a full Sagnac effect; see A. A. Michelson and H. G. Gale, ‘The Effect of the Earth's Rotation on the Velocity of Light’, Nature, 115 (1925), 566; and Michelson and Gale, ‘The Effect of the Earth's Rotation on the Velocity of Light’, The Astrophysical Journal, 61 (1925), 140–45. For a historical description of Sagnac-type experiments, see E. J. Post, ‘Sagnac Effect’, Reviews of Modern Physics, 39 (1967), 475–93.

³⁹The hypothesis of Silberstein's influence on Miller's research would be confirmed by a letter of Hale to Larmor, 21 December 1921, AIP, HP, roll 22.

⁴⁰Hale to Merritt, 29 November 1920; telegram Miller to Hale, 24 January 1921; Miller to Hale, 19 February 1921, AIP, HP, roll 93.

⁴¹Telegram Miller to Hale, 22 April 1921, AIP, HP, roll 92.

⁴²This sentence became famous when Pais used it as the title of his scientific biography of Albert Einstein, see Pais (note 28). The episode is quoted in several biographies. See, e.g., ibid., 113; and A. Fölsing, Albert Einstein: Eine Biographie (Frankfurt, 1993) [trans. Albert Einstein: A Biography (New York, 1997), 503].

⁴³‘Hope Soon to Prove if Einstein is Right’, The New York Times, 13 May 1921, 7; repr. in J. Illy, Albert Meets America: How Journalists Treated Genius during Einstein's 1921 Travels (Baltimore, 2006), 199–202.

⁴⁴Miller to Thomas C. Mendenhall, 2 June 1921, Worcester Polytechnic Institute (WPI), University Archives and Special Collections, G. C. Gordon Library, Thomas Corwin Mendenhall Papers, box 10, fol. 8; quoted also in Holton (note 8), 367. Miller repeated his opinion of Einstein's visit in a letter to Larmor, 9 June 1921, Royal Society Archives, Joseph Larmor Papers.

⁴⁵Shankland et al. (note 14), 167–68.

⁴⁶Swenson (note 1), 195.

⁴⁷Miller to Hale, 30 June 1921, AIP, HP, roll 93.

⁴⁸See Crelinsten (note 13).

⁴⁹Hale to Miller, 28 July 1921; and Miller to Lorentz, 22 August 1921, AIP, HP, roll 93. Unfortunately, I have not found Lorentz's answer, but he probably suggested that Miller repeat the experiments in other seasons. There is some evidence that Lorentz was really interested in Miller's ether-drift experiments as Einstein said to Shankland in R. S. Shankland, ‘Conversation with Albert Einstein’, American Journal of Physics, 31 (1963), 47–57.

⁵⁰Miller to Hale, 26 August 1921, AIP, HP, roll 93. Miller wrote in his diary (research notebook, 11 December 1921): ‘all effects are probably due to the instrument. This is the end!’; quoted in Shankland et al. (note 14), 168.

⁵¹Hale wrote: ‘Professor Dayton Miller […] has just repeated the Michelson-Morley experiment on Mount Wilson with negative result […] displacements of the fringes […] were finally proved to be of instrumental origin and almost wholly eliminated’, in Hale to Larmor, (note 39).

⁵²D. C. Miller, ‘Ether-drift Experiments at Mount Wilson Solar Observatory’, Physical Review, 19 (1922), 407–8 (407). Quoted also in Swenson (note 1), 200.

⁵³D. C. Miller, ‘The Significance of the Ether-Drift Experiments of 1925 at Mt. Wilson’, Science, 63 (1926), 433–43 (436). Miller repeated the same sentences in Miller (note 1), 219–20.

⁵⁴‘Bulletin of the American Physical Society’, vols. I and II; and ‘List of Members of the American Physical Society of July 1920’, Records of the American Physical Society in Niels Bohr Library and Archives, AIP. In 1902 there were 144 APS members. By 1920, there were more than 1,100. For a thorough analysis of the US physics community in the twentieth century, see D. J. Kevles, The Physicists: The History of a Scientific Community in Modern America (Cambridge, MA, 1987).

⁵⁵J. Lankford, American Astronomy: Community, Careers and Power, 1859–1940 (Chicago, 1997), 250. This treatise examines the history of the US astronomical community. For biographies of Miller, see R. S. Shankland, ‘Dayton C. Miller: Physics Across Fifty Years’, American Journal of Physics, 9 (1941), 273–83; and W. Fickinger, Miller's Waves: An Informal Scientific Biography (Cleveland, 2011).

⁵⁶Telegram Hale to Merriam, 29 November 1921, Washington D. C., Library of Congress, Manuscript Division, John Campbell Merriam Papers (MP), box 87, folder Hale/2; telegram Merriam to Hale, 29 November 1921; and Hale to Merriam, 30 November 1921, AIP, HP, roll 93.

⁵⁷The power of Hale, and after him Adams, as director of one of the biggest and most influential ‘great factory observatories’ in the USA as well as the role of competition in ‘the search for funds to support large-scale research institutions’ is described in Lankford (note 55), 185–235. Lankford argues that the directors of a few large institutions, such as the MWO, indisputably shaped the research programmes of US astronomy.

⁵⁸Augustus Trowbridge to Gano S. Dunn, 24 October 1922; and ‘Vote of the committee’, in NAS-NRC Archives: Building Records Group: P&E: Real Estate: Buildings: NAS-NRC: Construction: Materials: Acoustical Tiles: Akoustolith: 1907–1925. The committee formally thanked Miller and asked him for other suggestions about the acoustics the following year: Paul Brockett to Miller, 28 December 1922; Dunn to Miller, 7 May 1923; Dunn to Miller, 2 October 1923; and Miller to Dunn, 5 October 1923, in NAS-NRC Archives: Building Records Group: P&E: Real Estate: Buildings: NAS-NRC: Construction: Materials: Acoustical Tiles: Akoustolith: 1907–1925.

⁵⁹Even though Einstein never accepted Miller's interpretations of his data, he stressed that it was important to test Miller's findings because he was an ‘excellent experimenter’. Shankland (note 49), 51.

⁶⁰Miller to Hale, 15 June 1922; and Miller to Dunn, 6 December 1922, San Marino, CA, Huntington Library, Walter S. Adams Papers (WAP), fol. 46.802. Apart from his work on the acoustics of the NRC building, Miller did other work for scientific societies that left him no time for research. In 1922 Miller was the secretary of the APS. In addition, he was a leading member of the NRC committee for acoustics. In November 1922, this committee published ‘Certain Problem in Acoustics’, Bulletin of the National Research Council 4 (1922), 1–30.

⁶¹Miller to Dunn (note 60); and telegram Miller to Adams, 3 January 1923, Huntington Library, WAP, fol. 46.802.

⁶²Shankland et al. (note 14), 168. This hypothesis is unlikely because of the delay between Lorentz's visit and Miller's involvement in new trials.

⁶³Charles L. Poor, Gravitation Versus Relativity: A Non-Technical Explanation of the Fundamental Principles of Gravitational Astronomy and a Critical Examination of the Astronomical Evidence Cited as a Proof of the Generalized Theory of Relativity (New York/London, 1922). Poor quotes Miller's results on page 264.

⁶⁴Miller wrote: ‘I agree with everything that [Poor] says and feel that he has stated the situation regarding the Relativity Theory better than any one else’. Miller to Dunn (note 60).

⁶⁵Crelinsten used this title to frame the works of those scientists who challenged the acceptance of relativity in the USA; see Crelinsten (note 13), 243.

⁶⁶Crelinsten used this title to frame the works of those scientists who challenged the acceptance of relativity in the USA; see Crelinsten (note 13), for a thorough analysis of St. John's conversion, see K. Hentschel, ‘The Conversion of St. John: A Case Study on the Interplay of Theory and Experiment’, Studies in Context, 6 (1993), 137–94.

⁶⁷In the USA, merit was given also to the fact that the verifications came from US authorities in astronomy who had no prejudices in favour of Einstein's theories. Many of the principal US crusaders of general relativity theory in the early 1920s were not experts in its mathematical aspects, but only in its experimental verifications, e.g. Hale, Campbell, St. John and Adams; see Crelinsten (note 13) and Lankford (note 55).

⁷¹Miller to Reuterdahl, 13 December 1923 (note 69); Miller was probably referring to A. Reuterdahl, ‘The Origin of Einsteinism’, New York Times, 12 August 1923.

⁶⁸The hostility Reuterdahl felt towards Einstein himself rather than towards his theory is evident in some published papers, e.g. A. Reuterdahl, ‘Einsteinism: his fallacies and frauds’, University of St. Thomas Special Collection, O'Shaughnessy-Frey Library, Arvid Reuterdahl Papers (ARP), published online in http://content.clic.edu/u?/reuterdahl,257 (accessed 20 September 2010). See also A. Moatti, Einstein, un siècle contre lui (Paris, 2007).

⁶⁹Miller wrote that he had worked on the elimination of all the disturbing factors and felt that he had ‘made the apparatus proof against temperature effect’, in Miller to Reuterda Huntingon Library, 13 December 1923, O'Shaughnessy-Frey Library, ARP, box 4, fol. 33; see also Miller to Reuterdahl, 14 January 1924, O'Shaughnessy-Frey Library, ARP, box 4, fol. 33.

⁷⁰M. Wazeck, ‘Einstein's Sceptics: Who Were the Relativity Deniers?’, New Scientist, 2786 (2010), 48–51 (49). Several members of the Academy of Nations were critical of Einstein and his theories. Among them were the US astronomers Poor and Thomas J. J. See, the US engineer Charles F. Brush, and the German physicist Ernst J. L. Gehrcke. For a record of the anti-Einstein campaign in Germany and his relationship with Reuterdahl's Academy of Nations, see M. Wazeck, Einsteins Gegner (Frankfurt/New York, 2009). Even though Miller personally corresponded with several of its members, he does not seem to have joined the Academy of Nations.

⁷²Birkhoff said to Miller: ‘[I] cannot help hoping, out of a mere desire that a serious theoretical dilemma be avoided, that these results (of the future Ether-Drift experiments) shall be completely confirmatory of those originally obtained by Michelson and Morley (a null result)’. Birkhoff's statement was quoted by Miller in the letter: Miller to Reuterdahl, 14 January 1924 (note 69), [round brackets in the original]. Birkhoff's position could be an example of the attitude of US mathematicians towards special relativity theory. It is also representative because Birkhoff had no personal sympathy towards Einstein, but he understood that relativist physics was a tool of the scientific community that had no alternative theory. See M. Rothenberg, History of Science in United States: An Encyclopedia, (New York/London, 2001), 83. Birkhoff also wrote one of the first books that explained relativity in simple terms. G. D. Birkhoff, Relativity and Modern Physics (Cambridge, MA, 1923).

⁷³Miller to Adams, 21 May 1924, Huntington Library, WAP, fol. 46.802; and Miller to Reuterdahl, 11 June 1924, O'Shaughnessy-Frey Library, ARP, box 4, fol. 33.

⁷⁴Miller (note 1), 221.

⁷⁵Miller (note 1).

⁷⁶Miller to Adams, 8 December 1924, Huntington Library, WAP, fol. 46.802.

⁷⁷Miller (note 1), 221.

⁷⁸Miller (note 1), 222.

⁷⁹D. C. Miller, ‘Ether-drift Experiments at Mount Wilson’, Science, 61 (1925), 617–621 (621).

⁸⁰D. C. Miller, ‘Ether-drift Experiments at Mount Wilson’, Science, 620.

⁸¹See Darwin (note 5). Charles G. Darwin's description of the incredulity of the scientific community is limited to the reaction to Miller's announcement in this meeting.

⁸²‘Scientists Debate Recent Tests Made of Einstein Theory’, Washington Post, 29 April 1925. See also ‘Strikes A Blow Against Relativity’, New York Times, 29 April 1925; W. S. Buel, ‘Clevelander Bombs Einstein Theory’, Cleveland Plain Dealer, 29 April 1925; ‘Local Man Proves Ether Drifts, Refuting Einstein’, Cleveland Times, 6 May 1925, CWRU Archives, Papers of Dayton C. Miller 19IM2 (PDM), box 4, fol. 1.

⁸³L Silberstein, ‘D. C. Miller's Recent Experiments, and the Relativity Theory’, Nature, 115 (1925), 798–99 (798).

⁸⁴The press campaign increased the confusion by issuing paradoxical reports of the Michelson-Gale result. ‘Michelson Proves Einstein Theory’, New York Times, 9 January 1925, 2; quoted also in Swenson (note 1), 208.

⁸⁵Miller published two papers about the April 1924 MWO experiments in June and July 1925. Miller (note 79); and D. C. Miller, ‘Ether Drift Experiments at Mount Wilson’, Nature, 116 (1925), 49–50.

⁸⁶A. S. Eddington, ‘Ether-drift and the Relativity Theory’, Nature, 115 (1925), 870.

⁸⁷Slosson to Einstein (note 9).

⁸⁸For accounts of the role of Eddington in the diffusion and reception of Einstein's theories in the English-speaking world, see L. R. Graham, ‘The Reception of Einstein's Ideas: Two Examples from Contrasting Political Cultures’, in G. Holton and Y. Elkana (eds.), Albert Einstein: Historical and Cultural Perspectives (Princeton, 1982), 107–36; and P. A. M. Dirac, “The Early Years of Relativity”, in ibid., 79–90.

⁸⁹L. Silberstein, ‘Ether Drift and the Relativity Theory’, Nature, 116 (1925), 98.

⁹⁰For example, the Italian engineer Giovanni Giorgi tried to defend Silberstein's dragged-ether theory from Eddington's criticisms. G. Giorgi, ‘Ether Drift and Relativity’, Nature, 116 (1925), 132. On the other hand, several scientists sceptical of Miller's results quoted Eddington's criticisms.

⁹¹Slosson to Einstein (note 9).

⁹²Slosson to Einstein (note 9).

⁹³E. E. Slosson, ‘The Relativity Theory and the Ether Drift’, Science News, 62 (1925), viii; quoted also in Hentschel (note 15), 606.

⁹⁴Miller himself wrote a note in which he quoted Einstein's sentence to ‘show the consideration which is being given to the ether-drift experiments’. See Miller's undated manuscript in CWRU Archives, PDM, box 1, fol. 1; the French physicist André Metz wrote that there was some noise from the anti-relativists because of Einstein's declarations according to which the confirmation of Miller's results would invalidate the theories of relativity. Metz to Einstein, 8 January 1926, in A. Einstein, Oeuvres Choisies 4 - Correspondances Français : Lettres Choisies et présentées par Michel Biezunski (Paris, 1989), 212.

⁹⁵Slosson (note 93).

⁹⁶Einstein to Ehrenfest, 18 August 1925, AEA 10-109; Einstein to Millikan, 13 July 1925; and Einstein to Millikan, 1 September 1925, Pasadena, CA, Caltech Archives, Papers of Robert Andrews Millikan (PRM), fol. 39.7.

⁹⁷See Hentschel (note 15).

⁹⁸Einstein to Ehrenfest, 18 September 1925, AEA 10–112. The influence of temperature on this kind of experiment was clearly stated since the first MMT experiment, as Michelson made a similar calculation in his first paper about the ether-drift experiments. However, Michelson was referring to another temperature influence, namely the temperature expansion of the interferometer arms. A. A. Michelson, ‘The Relative Motion of the Earth and the Luminiferous Ether’, American Journal of Science, 22 (1881), 120–29.

⁹⁹This letter was lost, but Einstein's suggestion is reported in the response that Miller sent several months later, in May 1926, after the completion of his observations and the subsequent calculations. Miller to Einstein, 20 May 1926, AEA 17–274. Einstein's secretary Helen Dukas and Shankland tried to find Einstein's letter in the 1960s, but they were unsuccessful. Dukas to Shankland, 6 March 1963, AEA 17–275; Shankland to Dukas, 12 March 1963, AEA 17–276; and Shankland to Dukas, 22 May 1963, AEA 17–277.

¹⁰⁰Miller, Nature (note 85), 50.

¹⁰¹Ehrenfest informed Einstein of Lorentz's criticism in the letter Ehrenfest to Einstein, 16 October 1925, AEA 10–110. Thirring wrote a very detailed paper in German about his criticisms at the end of 1925. H. Thirring, ‘Kritische Bemerkungen zur Wiederholung des Michelson-Versuchs auf dem Mt. Wilson’, Zeitschrift für Physik, 35 (1926), 723–31.

¹⁰²W. F. G. Swann, ‘The Relation of the Restricted to the General Theory of Relativity and the Significance of the Michelson-Morley Experiment’, Science, 62 (1925), 145–49. Before him, this hypothesis was proposed by Dutch mathematician David van Dantzig. D. van Dantzig, ‘The Miller Effect and Relativity’, Nature, 116 (1925), 465.

¹⁰³W. F. G. Swann, ‘The Stokes-Planck Theory and the Michelson-Morley Experiment’, Nature, 116 (1925), 785.

¹⁰⁴Poor and Heber D. Curtis were the only scientists that publicly interpreted Miller's findings as a refutation of Einstein's theories, but they were linked to other US astronomers with anti-relativistic leanings, such as Thomas J. J. See and John A. Miller; see Crelinsten (note 13), 277.

¹⁰⁵Poor to Miller, 7 May 1925, Baltimore, Johns Hopkins University, Sheridan Library, Charles L. Poor Papers (CPP), folder D. C. Miller.

¹⁰⁶Adams to Miller, 5 June 1925, Huntingon Library, WAP, fol. 46.802.

¹⁰⁷Miller to Adams, 21 May 1925, Huntingon Library, WAP, fol. 46.802.

¹⁰⁸Miller to Adams, 9 July 1925, Huntingon Library, WAP, fol. 46.802.

¹⁰⁹Miller to Adams, 19 December 1925, Huntingon Library, WAP, fol. 46.802.

¹¹⁰He first had written the numerical value for the ether-drift as 12½ km/s, which he replaced with 8 km/s.

¹¹¹Telegram Miller to Adams, 27 December 1925, Huntington Library, WAP, fol. 46.802.

¹¹²This is demonstrated by the fact that Miller gave him $200 of the AAAS prize. Miller also wrote to Nassau that ‘I am fully conscious of my deep obligation to you for assistance in solving the Ether-Drift problem. It would be impossible for me to have presented a report at Kansas City if you had not come to the rescue in the splendid way you did in the last few days, including the work of Christmas Day’. Miller to Nassau, 5 January 1926; and Miller to Nassau, 23 February 1926, CWRU Archives, Jason John Nassau Papers 19IN2 (JNP), box 7, fol. 1.

¹¹³This address was published in April 1926, in Miller (note 53).

¹¹⁴This address was published in April 1926, in Miller (note 53), 438.

¹¹⁵Epstein to Einstein, 19 September 1925, Caltech Archives, Papers of Paul Sophus Epstein (PPE), fol. 3.34.

¹¹⁶Miller, (note 53), 437.

¹¹⁷Swenson (note 1), 212. According to Swenson, the prize was given by experts in the development of physical theories; in fact, the physicist Karl T. Compton was on the Award Committee.

¹²³D. Dietz, ‘U.S. Scientist after 6 Years Tells of Work’, Citizens Cairo Illinois, 29 December 1925, CWRU Archives, PDM, box 4, fol. 1 and D. Dietz, ‘Theory Pushed by Einstein is Given Setback’, the newspaper is unknown, but probably is Cleveland Plain Dealer, Miller's press reviews, CWRU Archives, PDM, box 4, fol. 1.

¹¹⁸Dietz wrote: ‘President Miller American Physical Society announces discovery of ether drift says quote my work annuls second postulate Einstein theory stop please cable collect two hundred work [sic] opinion press rates’. telegram Dietz to Einstein, 25 December 1925, AEA 17-266, courtesy Hebrew University of Jerusalem.

¹¹⁹Dietz published several articles about Miller's ether-drift as an anti-relativistic discovery. See Miller's press reviews in CWRU Archives, PDM, box 4. Einstein did not directly respond to Dietz's question, but he soon wrote a letter to his friend Michele Besso, in which he repeated that Miller's results were a consequence of temperature variations and that he never took them seriously. Einstein to Besso, 25 December 1925, in A. Einstein and M. Besso, Correspondance 1903–1955 (Paris, 1979), 127–28. The episode is analysed in Holton (note 8), 334–35.

¹²⁰‘Einstein Theory born on Heights’, Cleveland Plain Dealer, 24 December 1924; ‘Case School Scientific Discovery’, Jefferson Ohio Gazette, 19 December 1925; and ‘Earth's Flight through the Ether’, Cleveland News, 1 December 1925, CWRU Archives, PDM, box 4, fol. 1.

¹²¹Miller to Trautman, 7 December 1925, CWRU Archives, PDM, box 4, fol. 1.

¹²²D. Dietz, ‘U.S. Scientist after 6 Years Tells of Work’, Citizens Cairo Illinois, 29 December 1925, CWRU Archives, PDM, box 4, fol. 1.

¹²⁴Hentschel has shown that sensational reports also appeared in newspapers in other countries, citing German articles. Hentschel (note 15), 604. It seems, however, that Miller's own publicity and relationship with US journalists made the US press campaign of greater consequence to scientific activities.

¹²⁵‘Finds Our Universe Speeding to Dragon’, New York Times, 30 December 1925, 6.

¹²⁶O. Lodge, ‘Scientific Worthies: XLIV. – Albert Abraham Michelson’, Nature, 117 (1926), 1–6 (6).

¹²⁷O. Lodge, ‘On Prof. Miller's Ether Drift Experiment’, Nature, 117 (1926), 854.

¹²⁸V. Bush, ‘The Force between Moving Charges’, Journal of Mathematics and Physics, 5 (1926), 129–57 (133), quoted also in A. Grünbaum, ‘Logical and Philosophical Foundations of Special Relativity Theory’, American Journal of Physics, 23 (1955), 450–64 (459).

¹²⁹G. Strömberg, ‘Miller's Ether Drift Experiment and Stellar Motions’, Nature, 117 (1926), 482–83 (483).

¹³⁰H. Thirring, ‘Prof. Miller's Ether Drift Experiments’, Nature, 118 (1926), 81–2.

¹³¹The Trouton-Noble experiment was performed in 1903. It was the first electromagnetic ether-drift test and it confirmed the null result of the MM experiment. The result was published in F. T. Trouton and H. R. Noble, ‘The mechanical forces acting on a charged electric condenser moving through space’, Philosophical Transactions of the Royal Society A, 202 (1903), 165–81. For an analysis of the relativistic interpretations of this experiment, see M. Janssen, ‘A Comparison between Lorentz's Ether Theory and Special Relativity in the Light of the experiments of Trouton and Noble’ (Ph.D. thesis, Pittsburgh, 1995).

¹³²R. Tomaschek, ‘Über Versuche zur Auffindung elektrodynamischer Wirkungen der Erdbewegung in groben Höhen I’, Annalen der Physik, 76 (1925) 743–56.

¹³³A. Einstein, ‘Meine Theorie und Millers Versuche’, Vossiche Zeitung, 19 January 1926. This article was discovered by Hentschel; see Hentschel (note 15).

¹³⁴Epstein to Einstein (note 115).

¹³⁵Hentschel has already pointed out how peculiar it was that Einstein referred, not to Tomaschek's MMT experiment with fixed starlight, but instead to his repetition of the Trouton-Noble experiment; see Hentschel (note 15), 607. The reason is that Einstein was comparing an altitude ether-drift experiment with another altitude ether-drift experiment, since he was still convinced that Miller was explaining the MWO data with an ether-drift dependent on altitude.

¹³⁶C. Tolichus, ‘Einstein is ready to bet on his theory’, newspaper unknown, 16 January 1926; and ‘Einstein Bets Miller is Wrong’, Cleveland Plain Dealer, 16 January 1926, CWRU Archives, PDM, box 4, fol. 1.

¹³⁷C. Tolichus, ‘Einstein is ready to bet on his theory’, newspaper unknown, 16 January 1926; and ‘Einstein Bets Miller is Wrong’, Cleveland Plain Dealer,.

¹³⁸A few days later, an article reported Miller's statements: ‘The trouble with Prof. Einstein is that he knows nothing about my results […]. He has been saying for thirty years that the interferometer experiments in Cleveland showed negative results. We never said they gave negative results, and they did not in fact give negative results. He ought to give me credit for knowing that temperature differences would affect the results […]. I am not so simple as to make no allowance for temperature’, in ‘Goes to Disprove Einstein Wrong’, Cleveland Plain Dealer, 27 January 1926.

¹³⁹Draft of the letter Einstein to Tolichus, 11 January 1926, AEA 17-268/1.

¹⁴⁰This concern is also indicated by Metz to Einstein, 8 January 1926 (note 94). It is possible that Metz's letter reached Einstein while he was writing the letter to Tolichus, leading Einstein to state that he did not believe in an ether-drift explanation of Miller's results.

¹⁴¹Einstein to Millikan (note 96); and Einstein to Lorentz, 22 June 1926, AEA 16-608. Lorentz publicly expressed his interest in Miller's findings in H. A. Lorentz, ‘Physics in the New and the Old World’, in P. Zeeman and A. D. Fokker (eds.) Collected Papers, 9 vols. ('s-Gravenhage, 1935–1939), VIII, 404–17 (415); quoted by Hentschel (note 15), 604.

¹⁴²Einstein to Lorentz (note 141); Ehrenfest to Einstein (note 101); Metz to Einstein (note 94); Epstein to Einstein, 25 July 1925, Caltech Archives, PPE, fol. 3.34; Cohn to Einstein, 11 September 1925, AEA 17-263; the wife of M. Born wrote to Einstein that Born doubted the reliability of Miller's instrument after his visit to Mount Wilson in Hedi Born to Einstein, 11 April 1926, in A. Einstein, H. Born and M. Born, Scienza e vita, lettere 1916–1955 (Torino, 1973), 107.

¹⁴³H. T. Hufford, ‘Is the Experimental Evidence Conclusive?’, in R. Carmichael et al., A Debate on the Theory of Relativity (Chicago/London, 1927), 64–89 (75).

¹⁴⁴H. T. Davis, ‘The Experimental Verification of Relativity’, in ibid., 90–116.

¹⁴⁵This way of considering the special theory of relativity was expressed by Robert A. Millikan in ‘Albert Einstein on His Seventieth Birthday’, Reviews of Modern Physics, 21 (1949), 343–45. Holton later indicated that this view was widely accepted; see Holton (note 8), 272–98.

¹⁴⁶For the empirical approach of the US scientific community towards relativity, see Goldberg (note 12), 241–319; see also Crelinsten (note 13), 321–25. Goldberg also pointed out that the first US textbooks and monographs about relativity emphasized empirical results and described special relativity theory as an inductive generalization of the null result of the MM experiment.

¹⁴⁷Holton writes that ‘the Nobel award to Michelson had for American science some of the same significance in terms of increased national self-esteem as did Yukawa's Nobel prize in physics for Japanese science’, in Holton (note 8), 356.

¹⁴⁸It is important to note that most English-language papers on Miller's experiments were published by Science and Nature, that is, comprehensive scientific journals. In particular, Science was the official journal of the AAAS.

¹⁴⁹Epstein to Einstein (note 115).

¹⁵⁰Piccard to Einstein, 21 September 1925, AEA 19-211.

¹⁵¹Piccard to Einstein, 20 November 1925, AEA 19-214; Piccard to Einstein, 14 October 1925, AEA 19-212; Piccard to Einstein, 21 October 1925, AEA 19-213.

¹⁵²Piccard to Einstein, 7 March 1926, AEA 19-215; Einstein to Piccard, 14 March 1926, AEA 19-216.

¹⁵³Piccard to Einstein, 30 July 1926, AEA 19-220; Einstein to Millikan, 8 January 1927, Caltech Archives, PRM, fol. 39.7. The experiments were performed at an altitude of 2500 m and 4500 m above sea level.

¹⁵⁴A. Piccard and E. Stahel, ‘L'expérience de Michelson, réalisée en ballon libre’, Comptes Rendus, 183 (1926), 420–21.

¹⁵⁷Kennedy to Adams, 25 July 1924, Huntington Library, WAP, fol. 38.650.

¹⁵⁵R. Kennedy, ‘Another Ether-Drift Experiment’, Physical Review, 20 (1922), 26–33.

¹⁵⁶Kennedy to Hale, 2 May 1924, Huntington Library, WAP, fol. 38.650.

¹⁵⁸Adams to Kennedy, 31 July 1924, Huntington Library, WAP, fol. 38.650.

¹⁵⁹R. J. Kennedy, ‘A Refinement of the Michelson-Morley Experiment’, Publications of the National Academy of Sciences, 12 (1926), 621–29 (628).

¹⁶⁰K. K. Illingworth, ‘A Repetition of the Michelson-Morley Experiment Using Kennedy's Refinement’, Physical Review, 30 (1927), 692–96.

¹⁶¹Contemporary anti-relativists do not agree with the null ether-drift interpretation of Illingworth's data; see Munera (note 2). Commenting on the anti-relativistic analyses of the MMT experiments is beyond the scope of this paper. However, it suffices to say that these analyses have no significant presence in the contemporary scientific community.

¹⁶²See, for example, F. A. Jenkins and H. E. White, Fundamentals of Optics (2^nd ed., New York/Toronto/London, 1950), 398; F. W. Van Name, Modern Physics: Developments of the Twentieth Century (New York, 1952), 84; and F. K. Richtmeyer, Introduction to Modern Physics (2^nd ed., New York, 1934), 715. Sometimes, Miller's experiments were even quoted as experiments that confirmed the null result; see H. M. Schwartz, Introduction to Special Relativity (New York, 1968), 35.

¹⁶³There are several accounts of the relation between Michelson and his ‘beloved ether’, as well as of his discomfort over the relevant role the MM experiment played in the acceptance of the special relativity theory, e.g. Holton (note 8), 285.

¹⁶⁴The historian of science Richard Staley has recently shown that Michelson was interested more in the different technological uses of his interferometer than in the null result of his experiment. R. Staley, Einstein's Generation: The Origins of the Relativity Revolution (Chicago/London, 2008).

¹⁶⁵A. A. Michelson, ‘The Relative Motion of Earth and Ether’, The American Journal of Science, 3 (1897), 475–78.

¹⁶⁶Hale to Miller (note 32).

¹⁶⁷Michelson made the earlier measurements at the MWO in 1921, see Hale to Miller, 26 July 1921, AIP, HP, roll 93; but he did not publish the final results until April 1925, after having changed the location from Mount Wilson to Clearing, IL.

¹⁶⁸Epstein to Einstein (note 115); Einstein to Millikan (note 96).

¹⁶⁹See Michelson's correspondence in Annapolis, MD, US Naval Academy (USNA), Nimitz Library Special Collection and Archives Division, Albert A. Michelson Papers MS 347 (AMP), box 1.

¹⁷⁰Undated handwritten note in Huntington Library, WAP, box 46, fol. Michelson 1925.

¹⁷¹Adams to Michelson, 24 November 1926, USNA, AMP, box 1 [emphasis in the original].

¹⁷²A. A. Michelson et al., ‘Conference on the Michelson-Morley Experiment: Held at the Mount Wilson Observatory Pasadena California, February 4 and 5, 1927’, Astrophysical Journal, 63 (1928), 341–402 (345).

¹⁷³Lankford (note 55), 188.

¹⁷⁴It is of interest that Merriam's positive response with respect to the CIW economical support for the Michelson-Pease-Pearson experiment arrived only a few days before Adams wrote his communication to Michelson. Merriam to Adams, 15 November 1926, Huntington Library, WAP, box 41, fol. Merriam 1926 July–December. The fact that Adams' request to the CIW executive committee preceded Kennedy's communication to the NAS also requires further attention. Adams to Merriam, 20 September 1926; and Adams to Merriam, 27 September 1926, Huntington Library, WAP, box 41, fol. Merriam 1926 July–December.

¹⁷⁵Pease to Mathews, 12 July 1926; and Pease to Mathews, 18 October 1926, Huntington Library, Francis G. Pease Papers (FPP), box 3, fol. misc. corr. II.

¹⁷⁶Michelson et al. (note 172), 345.

¹⁷⁷C. T. Chase, ‘A repetition of the Trouton-Noble Ether-Drift Experiment’, Physics Review, 28 (1926), 378–83.

¹⁷⁸A. Piccard and E. Stahel, ‘L'absence du vent d’éther au Rigi’, Comptes Rendus, 185 (1927), 1198–200.

¹⁷⁹C. T. Chase, ‘The Trouton-Noble Ether-Drift Experiment’, Physics Review, 30 (1927), 516–19.

¹⁸²Michelson to Pease, 23 March 1928, USNA, AMP, box 1 [emphasis mine].

¹⁸⁰See Pease's correspondence with Mathews of Crucible Steel of America about Invar, Huntington Library, FPP, box 3, fol. misc. corr. II. This correspondence ended when Pease made the last order in Pease to Mathews, 15 August 1927. For Pease's observations, see Notebook of ether-drift Data, Huntington Library, FPP, box 5. The technical problems are well described in Swenson (note 1).

¹⁸¹Adams to Michelson, 27 December 1927, USNA, AMP, box 1.

¹⁸³Adams to Gale, 16 January 1930, USNA, AMP, box 2.

¹⁸⁴A. A. Michelson, F. G. Pease and F. Pearson, ‘Repetition of the Michelson-Morley Experiment’, Nature, 123 (1929), 88; and A. A. Michelson, F. G. Pease and F. Pearson, ‘Repetition of the Michelson-Morley Experiment’, Journal of the Optical Society of America, 18 (1929), 181–82 (182).

¹⁸⁵‘Holds Light Test Supports Einstein’, New York Times, 3 November 1928, 21.

¹⁸⁶Telegram Adams to Michelson, 24 November 1928, USNA, AMP, box 1; telegram Seares to Michelson, 23 November 1928, Huntington Library, Frederick Hanley Seares Papers (FSP), box 12, fol. Michelson.

¹⁸⁷Seares to Michelson, 28 November 1928, Huntington Library, FSP, box 12, fol. Michelson.

¹⁸⁸Seares to Michelson, 28 November 1928, Huntington Library, FSP, box 12.

¹⁸⁹Miller continued to perform experiments in Cleveland and to publish reports confirming ether-drift and solar motion; see D. C. Miller, ‘Ether Drift Experiments in 1929 and other Evidence of Solar Motion’, Journal of the Royal Astronomical Society of Canada, 24 (1930), 82–84. For quotations in newspapers, see ‘Miller Challenges Einstein: Explains Ether Drift Research and Function of the Interferometer’, The Case Alumnus, December 1929, 10–12; and ‘Dr. D. C. Miller Declares Ether Drift Found; Reports Experiments Contradicting Einstein’, New York Times, 24 October 1929.

¹⁹⁰Adams to Gale, 3 January 1930, USNA, AMP, box 2.

¹⁹¹Gale to Adams, 9 January 1930, USNA, AMP, box 2.

¹⁹²Gale to Adams, 21 January 1930, Huntington Library, WAP, box 46, fol. Michelson 1930–32; and Adams to Gale, 16 January 1930, USNA, AMP, box 2.

¹⁹³Adams to Michelson, 27 January 1930, Huntington Library, WAP, box 46, fol. Michelson 1930–32. Unfortunately, I could not locate the response to this letter and it is unclear whether Michelson ever wrote one.

¹⁹⁴An extended version of this address was published two years later in C. St. John, ‘Observational Basis of General Relativity’, Publications of the Astronomical Society of the Pacific, 44 (1932), 277–95.

¹⁹⁵Michelson to Adams, 5 April 1930, Huntington Library, WAP, box 46, fol. Michelson 1930–32. Adams requested for this report in Adams to Michelson, 26 March 1930, Huntington Library, WAP, box 46, fol. Michelson 1930–32.

¹⁹⁶St. John to Adams, 23 April 1930, Huntington Library, WAP, fol. 59.132.

¹⁹⁷St. John's role was emphasized in newspapers, e.g. ‘Say Tests Upset Ether-Drift Theory’, New York Times, 20 April 1930.

¹⁹⁸Crelinsten (note 13), 310.

¹⁹⁹St. John to Campbell, 2 May 1930, quoted in ibid., 311. A similar sentence is in St. John to Adams, 6 May 1930, Huntington Library, WAP, fol. 59.132. The list of the ‘men who count’ reflects some perceptions about the role of authority in the US scientific community: George Burgess (Head of the Bureau of Standards), Ernest W. Brown, Swann (director of the Bartol Research Foundation of the Franklin Institute), Franck Schlesinger (director of the Yale University Observatory), Oswald Veblen, George Birkhoff, Karl T. Compton (president of the Massachusetts Institute of Technology), and his brother, Arthur H. Compton (Nobel Prize winner in Physics). St. John's list included astronomers, mathematicians, and physicists, all of them authorities in their respective disciplines. Moreover, some had institutional roles and determined the research programmes for their institutions.

²⁰⁰Joos (note 6).

²⁰¹St. John (note 194), 281.

²⁰²Miller (note 1).

²⁰³Galison (note 11), 2.

²⁰⁴G. Joos, ‘Note on the Repetition of the Michelson-Morley Experiment’, Nature, 45 (1934), 114.

²⁰⁵D. C. Miller, ‘Comments on Dr. Georg Joos's Criticism on the Ether-Drift Experiment’, Nature, 45 (1934), 114.

²⁰⁷Adams to Gale, 19 January 1934, Huntington Library, WAP, fol. 25.447.

²⁰⁶Gale to Adams, 15 January 1934, Huntington Library, WAP, fol. 25.447.

²⁰⁸St. John to Adams, 23 April 1930, Huntington Library, WAP, fol. 59.132.

²⁰⁹The most influential book to spotlight Miller's work was R. B. Lindsay and H. Margenau, Foundations of Physics (New York, 1936). As an exception, the 2^nd edition was written after Shankland's work, but the sentences about Miller's work remain unchanged: Miller's experiments are quoted as indicating ‘a genuine positive result’. The authors considered that the entire question of the motion of the earth through the ether was ‘still an open [question]’ and affirmed that further work on it was necessary. Ibid. (2nd ed., New York, 1957), 326.

²¹⁰Poor accused the scientific editors who did not accept his anti-relativistic papers; see the correspondence between Poor and James McKeen Cattel, editor of Science, Sheridan Library, CPP, fol. Cattel.

²¹¹Miller wrote, ‘My interest in you and your work is very real and is supported by full confidence in your character, in your intelligence, and in your good judgment. No one could be better qualified to carry on work which has been the interest of my whole life’, Miller to Shankland, 17 September 1939, CWRU Archives, A11-016, box 1. When I made my archival research in Cleveland (may 2010) all the documents now filed in the CWRU Archives with the accession number A11-016 were under Prof. Fickinger's custody in his office. I am indebted to Prof. Fickinger for calling my attention to these documents, and for the permission to study them when they were not filed in the CWRU Archives.

²¹²The influence of Shankland’ s interviews was increased by their use in Holton (note 8).

²¹³Interview with R. S. Shankland, ‘Memories of Dayton Miller’, 15 December 1981, 3, CRWU Archives, RSP, 7PI, box 115; see also ‘Oral history interview of Robert S. Shankland by L. S. Swenson Jr., on August 20 and 21 1974, OH451, Niels Bohr Library & Archives, AIP, College Park, MD, USA, www.aip.org/history/ohilist/4886_1.html’.

²¹⁴Miller to G. S. Fulcher, 12 February 1938, AIP, Papers of Gordon Scott Fulcher; Miller to Shankland, 23 January 1935, CWRU Archives, RSP, A11-016, box 1; and Miller to Poor, 12 February 1938, Sheridan Library, CPP, folder D. C. Miller.

²¹⁵Miller to Shankland, 13 March 1935, CRWU Archives, RSP, A 08-019, fol. 1.

²¹⁶Davisson to Miller, 29 May 1936, CWRU Archives, PDM, box 1, fol. 8. In 1936, he retired after 46 years of service. The president of Case, William Wickenden, held a ceremony in his honour and bestowed on him the position of Honorary Professor of Physics. The scientific world responded by writing many letters about his work, but very few letters cited esteem for his work on the ether-drift experiments. For some, Miller's persistence in claiming an ether-drift signal remained a stain on his scientific reputation.

²¹⁷Shankland's first historical account of Michelson's work at Case was published in 1949. R. S. Shankland, ‘Michelson at Case’, American Journal of Physics, 17 (1949), 487–90.

²¹⁸Attachment to the letter Shankland to Einstein, 27 October 1952, CWRU Archives, RSP, A11-016, box 1. These sentences appeared unchanged in Shankland (note 49), 55.

²²⁰This letter was analysed by Holton (note 8), 303. Einstein wrote in German. According to Fickinger, the English translation was made by Einstein's secretary Helen Dukas. Einstein's entire statement was published in R. S. Shankland, ‘The Michelson Morley Experiment’, American Journal of Physics, 31 (1964), 16–35 (35), courtesy Princeton University Press.

²¹⁹Einstein wrote: ‘Your resume does not correspond exactly with the thoughts I was endeavouring to express’, Einstein to Shankland, 29 October 1952, CWRU Archives, RSP, A11-016, box 1, courtesy Princeton University Press.

²²¹Shankland to Stachel, 11 January 1978, CWRU Archives, RSP, A11-016, box 1.

²²²See P. Langevin, ‘Sur la théorie de relativité et l'expérience de M. Sagnac’, Comptes Rendus, 205 (1921), 831–34; this is one of the first relativistic derivations of the Sagnac Effect. For a historical analysis of this derivation in the local context of French scientific community, see R. Lalli, ‘Effetto Sagnac (1913): Storia di un mancato dibattito nella Francia degli anni '20’, Quaderni di Storia della Fisica, 17 (2011), 47–81.

²²³Einstein to Shankland, 17 September 1953, CWRU Archives, RSP, A11-016, box 1.

²²⁴Foldy to Shankland, 3 August 1953, CWRU Archives, RSP, A 08-19, box 1, fol. 1. In the CWRU Archives there are some pages of Shankland's paper concerning the relativistic derivation of the Michelson-Gale experiment. Foldy wrote the letter after having read this paper, and expressed his regrets to Shankland that the majority of the paper could be misunderstood, since Shankland's did not mention the fact that the effect could have non-relativistic explanations.

²²⁵Shankland (note 49), 51.

²²⁶Shankland (note 49), 51. [round brackets in the original].

²²⁷Later, Shankland expressed the importance of his meetings with Einstein and described in several publications Einstein's encouragement of his plan to explain Miller's data; see Shankland to Dukas, 3 January 1972, AEA 20-317.

²²⁸Gardner's theory and its application to the MMT experiment were published in G. H. F. Gardner, ‘Rigid-Body Motions in Special Relativity’, Nature, 170 (1952), 243; and J. L. Synge, ‘Gardner's Hypothesis and the Michelson-Morley Experiment’, Nature, 170 (1952), 243–44.

²²⁹Synge to Nassau, 15 October 1951; Shankland to Synge, 29 October 1951; Synge to Shankland, 3 November 1951; Shankland to Synge, 8 January 1952; Synge to Shankland, 11 January 1952; Shankland to Synge, 21 January 1952; Synge to Shankland, 5 February 1952; Shankland to Synge, 28 February 1952; Synge to Shankland, 8 March 1952; and Shankland to Synge, 21 March 1952, CWRU Archives, RSP, A 08-19, box 1, fol. 1.

²³⁰Shankland (note 49), 53.

²³¹R. W. Ditchburn and O. S. Heavens, ‘Relativistic Theory of a Rigid Body: Letter to the Editor’, Nature, 170 (1952), 705.

²³²Pike to Shankland, 9 January 1952, CWRU Archives, RSP, A 08-19, box 1, fol. 3.

²³³R. L. Stearns, ‘A Statistical Analysis of Interferometer Data’ (MS Thesis, Case Institute of Technology, Physics Dept., 1952).

²³⁴Foldy was interested in more contemporary theoretical subjects and performed some research far from Cleveland, whereas Shrader was involved in experiments with the Case betatron; see W. Fickinger, Physics at a Research University: Case Western Reserve 1830–1990 (Cleveland, 2006), 71–74 and 112–20.

²³⁵Shankland to Foldy, 8 January 1954, CWRU Archives, RSP, A 08-19, box 1, fol. 1. Foldy was working in the Institute for Theoretical Physics in Copenhagen during the year 1954, so he could only help his Case colleagues by mail.

²³⁶This sentence appears in the first draft as well as in the final report. However, it does not appear in all drafts. R. S. Shankland, S. W. McCuskey and F. C. Leone, 1^st Draft of ‘New analysis of the Interferometer Observations of Dayton C. Miller’, 6, CWRU Archives, RSP, A11-016, box 1.

²³⁷Elrod calculated the same value twice before the shipment of the first draft. Notes of 9 February 1952 and 26 February 1952, CWRU Archives, RSP, A11-016, box 1.

²³⁸Shankland et al. (note 236), 16.

²³⁹L. L. Foldy, ‘Critical remarks apropos “A New Analysis of the Interferometer Observations of Dayton C. Miller”’, CWRU Archives, RSP, A11-016, box 1, attached to the letter Foldy to Shankland, 2 March 1954, CWRU Archives, RSP, A 08-19, box 1, fol. 1.

²⁴⁰R. S. Shankland, S. W. McCuskey and F. C. Leone, 2^nd Draft of ‘New analysis of the Interferometer Observations of Dayton C. Miller’, 14, CWRU Archives, RSP, A11-016, box 1.

²⁴¹Shankland to Foldy, 25 March 1954, CWRU Archives, RSP, A 08-19, box 1, fol. 1. The second draft of the paper was sent to Foldy with this letter.

²⁴²The temperature difference inside an arm as a function of the temperature difference between a wall and the average room temperature was 0.00005Tw. The difference between the two arms had to be 0.001° C. So 0.001° C = 0.00005Tw. This implied that Tw = 20° C.

²⁴³L. L. Foldy, ‘Remarks concerning “A New Analysis of the Interferometer Observations of Dayton C. Miller-2nd draft”’, 2 June 1954, CWRU Archives, RSP, A11-016, box 1 [emphasis in the original].

²⁴⁴Comments of M. J. Klein on Shankland et al. (note 240), courtesy of Prof. W. Fickinger. For an account of Klein's work at Case, see Fickinger (note 234), 121–22.

²⁴⁵Shankland to R. M. Bozorth, 15 April 1954; Bozorth to Shankland, 21 April 1954; Shankland to Bozorth, 5 May 1954; and Joos to Kuerti, 17 May 1954, CWRU Archives, RSP, A11-016, box 1. In these letters the magnetostriction was still considered a possible cause of the effect.

²⁴⁶This draft, dated 7 July 1954, was the fourth; the third draft of 2 July 1954 had only some differences in the order in which the arguments were presented.

²⁴⁷The authors confirmed, ‘It is impossible to carry through calculations which would accurately predict the overall behaviour of the interferometer due to temperature anomalies’. R. S. Shankland, S. W. McCuskey and F. C. Leone, 3^rd Draft of ‘New analysis of the Interferometer Observations of Dayton C. Miller’, 23, CWRU Archives, RSP, A11-016, box 1.

²⁴⁹Einstein to Shankland, 31 August 1954, CWRU Archives, RSP, A11-016, box 1, courtesy of Princeton University Press.

²⁴⁸It is not possible to list all the positive responses Shankland received. The most significant were: Panofsky to Shankland, 15 November 1954; R. Birge to Shankland, 3 August 1954; E. Kemble to Shankland, 28 October 1954; M. Born to Shankland, 18 August 1964; and Margenau to Shankland, 16 September 1954, CWRU Archives, RSP, A11-016, box 1. For Dyson's role in the development of theoretical physics, see S. Schweber, QED and the Men Who Made It: Dyson, Feynman, Schwinger and Tomonaga (Princeton, 1994).

²⁵⁰Dyson to Shankland, 12 October 1954, CWRU Archives, RSP, A11-016, box 1.

²⁵¹Shankland to Dyson, 23 November 1954, CWRU Archives, RSP, A11-016, box 1.

²⁵²Shankland to Goudsmit, 4 December 1954, CWRU Archives, RSP, A11-016, box 1.

²⁵³See, e.g., Maurice Allais to Shankland, 10 October 1955, CWRU Archives, RSP, A11-016, box 1.

²⁵⁴D. Dietz, ‘Dayton C. Miller and the Popularization of Science’, Science, 93 (1941), 319–20.

²⁵⁵Eckart to Shankland, 3 August 1954; and Panofsky to Shankland, 15 September 1954, CWRU Archives, RSP, A11-016, box 1.

²⁵⁶Panofsky to Shankland, (note 255).

²⁵⁷Eckart to Shankland, (note 255). It is easy to see in these ‘lesser men’ all the scientists who belligerently fought against relativity without reasonable discussion or because of racial prejudice. Without going into this issue, it is possible to affirm that Miller, according to Shankland, did not agree with German racial politics against the Jews. In fact, he loved Germany and its music, but he stopped visiting Germany after Hitler became the Chancellor (Reichskanzler) in 1933; see Shankland (note 213).

²⁵⁸Synge to Shankland, 12 August 1954, CWRU Archives, RSP, A11-016, box 1, courtesy Prof. Cathleen Synge Morawetz.