This paper was originally written while I was attached to the Unit for History and Social Aspects of Science at the Free University of Amsterdam.

A shorter version of this paper was read at the annual meeting of the History of Science Society in Dallas, Texas, on 30 December 1977. My thanks to Martin J. S. Rudwick for his advice and help, and to Charles C. Gillispie for his thought-provoking criticism.

¹ Ampère, André-Marie, Théorie des phénomènes électro-dynamiques, uniquement déduite de l'expérience, Paris, 11 1826Google Scholar; this was an earlier-published and slightly different separate printing of ‘Mémoire sur la théorie mathématique des phénomènes électro-dynamiques uniquement déduite de l'expérience …’, Mémoires de l'Académie royale des sciences de l'Institut de France, 1823, 6, (published 1827), 175–387Google Scholar, by which name it has become universally known.

² On ‘Laplacian physics’ see the references cited in n. 29, below. Herivel placed Ampère, Laplace, and Poisson together in a mechanico-molecular school in opposition to the analytico-positivists such as Fourier and Comte; see Herivel, John W., ‘Aspects of French theoretical physics in the nineteenth century’, British journal for the history of science, 1966–1967, 3, 109–132CrossRefGoogle Scholar (121). Comte, however, had in 1835 already assimilated Ampère's electrodynamics into the positivist tradition; see Comte, Auguste, Cours de philosophie positive, 2 vols., Paris, 1975, i, leçon XXXIV, p. 548.Google Scholar

³ Tricker, R. A. R., Early electrodynamics: the first law of circulation, Oxford, 1965, pp. 15, 98Google Scholar; Agassi, Joseph, Towards an historiography of science, The Hague, 1963, pp. 22–3Google Scholar; Williams, L. Pearce, ‘Ampère's electrodynamic molecular model’, Contemporary physics, 1962–1963, 4, 113–23 (122)CrossRefGoogle Scholar; idem, The physical sciences in the first half of the nineteenth century: problems and sources', History of science, 1962, 1, 1–15 (6)Google Scholar; idem, Michael Faraday, a biography, London & New York, 1965, pp. 140, 161, 263Google Scholar; and idem, The origins of field theory, New York, 1966, p. 67Google Scholar. By 1970 Williams realized that Ampère's theory of electrodynamics ‘was not immediately and universally accepted’: see his article ‘André-Marie Ampère’, in Gillispie, C. C. (ed.), Dictionary of scientific biography, New York, 1970, i, 139–147 (145).Google Scholar

Brown wrote that ‘The Académe's attitude to Ampère's early papers were mixed, though generally magnanimous. According to Delambre's slightly retrospective summary of the scientific highlights of 1820, the new electrodynamic theory was widely and quickly accepted. He implies that most of the Académie's members immediately adopted Ampère's views and found every recently discovered fact to be in perfect accord with his theory’; see Brown, Theodore M., ‘The electric current in early nineteenth-century French physics’, Historical studies in the physical sciences, 1969, 1, 61–103CrossRefGoogle Scholar (89). Although favourable to Ampère, ‘Delambre's’ report (read on 2 April 1821) gave no indication of the reception of Ampère's work by others; see Delambre, Jean-Baptiste-Joseph, ‘Analyse des travaux de l'Académie royale des sciences, pendant l'année 1820. Partie mathématique’, Mémoires de l'Académie royale des sciences de l'Institut de France, 1819–1820, 4, (published 1824), cxxvii–cciii (cxxxvii–cxlviii)Google Scholar. Moreover, the relevant section of this report was almost certainly written by Ampère himself; see his letter of 25 March 1821 to de La Rive, Gaspard in de Launay, Louis, (ed.), Correspondance du grand Ampère, 3 vols., Paris, 1936–1943, ii, 568Google Scholar, and ‘exposé sommaire des divers mémoires lus par Mr. Ampère á l'Académie royale des sciences de Paris, sur l'action mutuelle de deux courans électriques, et sur celle qui existe entre un courant électrique et le globe terrestre ou un aimant’, Bibliothèque universelle des sciences, belles-lettres et arts, section ‘Sciences et arts’, 1821, 16, 309–19Google Scholar, which is identical to the pages cited from Delambre's report. To be sure, Brown did recognize that ‘Biot did not share in this enthusiastic applause, for … he remained the spokesman for the old electrostatic pile theory. And in Ampère's eyes, Biot's opinions, bound up as they were with Coulomb's theory of magnetism, still carried the day’ (ibid., p. 90). Although proper clarification of the point would exceed the bounds of this paper, Ampère's differences with Biot had virtually nothing to with theories of the pile.

⁴ This was recognized by his contemporaries; see Sainte-Beuve, Charles-Augustin and Littré, Emile, ‘Illustrations scientifiques III. M. Ampère’, Revue des deux mondes (Paris), 1837, 9, 389–422Google Scholar (‘I. Sa jeunesse, ses études diverses, ses idées métaphysiques, etc.’, by Sainte-Beuve) and 422–39 (‘II. Physique’, by Littré) (432); Arago, François, ‘Ampère. Biographie lue par extraits en séance publique de l'Académie des sciences, le 21 août 1839’, in Barral, J. -A. (ed.), Oeuvres complètes de François Arago, 17 vols., Paris, 1854–1862, ii, 1–116Google Scholar (58–9, 68–9). For Ampère's feeling that his work met with stubborn opposition see his Correspondance, op. cit. (3), ii, 571–2, 653, 678, 680Google Scholar; iii, 907, and the ‘Réponse de M. Ampère á la lettre de M. Van Beck [sic], sur une nouvelle expérience électro-magnétique’, Journal de physique, de chimie, d'histoire naturelle et des arts, 1821, 93, 447–67 (447)Google Scholar. This point requires a more extensive discussion than can be given here. Suffice it to say that no evidence for the contrary assertion has ever been adduced (see n. 3, above). My first awareness of this state of affairs came in conjunction with a paper I wrote in June 1969 for Prof. Charles Gillispie's graduate seminar at Princeton University (‘On the reception of Ampère's electromagnetic theory in France’).

⁵ Perhaps the most important such case was Antoine-César Becquerel; see, for example, ‘Du développement de l'électricité par le contact de deux portions d'un même métal, dans un état suffisamment inégal de température; des piles voltaïques construites avec des fils d'un même métal et même avec un seul fil, et de quelques effets électriques qui naissent dans les combinaisons chimiques’, Annales de chimie et de physique, 1823, 23, 135–54Google Scholar (135–6, 146); ‘Des effets électriques qui se développent pendant divers actions chimiques’, ibid., 244–58 (248); and ‘Considérations générales sur les changemens qui s'opèrent dans l'état électrique des corps, par l'action de la chaleur, du contact, du frottement et de diverses actions chimiques, et sur les modifications qui en résultent quelquefois dans l'arrangement de leurs parties constituentes’, ibid., 1831, 46, 265–94, 337–60 (268–9).

⁶ The most famous example of Ampère's ‘public positivism’ is probably the first half-dozen pages of the work cited in n. 1 above. By ‘positivism’ I mean the view that objective knowledge of nature is limited to the formulation of mathematico-descriptive laws of phenomena which warrant no commitment to any ‘underlying’ image of reality. Newtonian action at a distance was the paradigmatic mathematico-descriptive law which said nothing about the physical cause of universal gravitation. The central role Biot played in propagandizing for this dernarcationist ideology, both in his scientific and in his popular writings, remains to be studied.

⁷ Ampère, , letter of 2 07 1824Google Scholar, in Correspondance, op. cit. (3), ii, 658.Google Scholar

⁸ Ampère, undated letter to Faraday, placed by de Launay at the beginning of 1825, ibid., p. 675.

⁹ Ampère, letter of 5 August 1826 to Auguste de La Rive, ibid., p. 686. Ampère, wrote ‘today, 30 August 1826’ in op. cit. (1), 196Google Scholar (or p. 368 of the Mémoires eidition). For an extended account of Ampère's physical picture see the Appendix, above.

¹⁰ I use ‘phenomenological’ to mean ‘limited de facto to the description of experience’, and to imply a less principled ideological stance than ‘positivistic’. The earliest reference I have found to Ampère's conception of the current as a series of decompositions and recompositions of a neutral electric fluid is ‘Extrait d'une lettre de Mr. Ampère au Prof. [Gaspard] De La Rive’, dated 15 May 1821, Bibliothèque universelle des sciences, belles-lettres et arts, section ‘sciences et arts’, 1821, 17, 192–4 (193)Google Scholar. In October 1820 he described the current as consisting of a double stream of oppositely directed positive and negative electric fluids, although from the context it is possible that Ampère was describing what he took to be the generally received notion; see ‘Mémoire présenté á l'Académie royale des sciences, le 2 octobre 1820, où se trouve compris le résumé de ce qui avait été lu á la même Académie les 18 et 25 septembre 1820, sur les effets des Courans électriques’, Annales de chimie et de physique, 1820, 15, 59–76Google Scholar (64, 69, 72). There are several inconsistencies regarding Ampère's views on the electric current during that period. In general it should be borne in mind that his chief interest then lay in distinguishing between the effects of tension and current electricity, and in working out his theory of magnetism.

¹¹ Littré, , op. cit. (4), pp. 427–8Google Scholar; Agassi, , op. cit. (3), pp. 20–3 and 70Google Scholar; Williams, , ‘Ampère's electro-dynamic molecular model’, op. cit. (3), p. 117Google Scholar; Williams, , in DSB, op. cit. (3), p. 143Google Scholar. At this last Williams said ‘it would appear that Oersted's discovery suggested to Ampère that two current-carrying wires might affect one another’, and referred to Bibliothèque universelle, 1821, 17, 23Google Scholar; however that reference—to an account of the Academy meeting of 25 September 1820—supports no such reconstruction. More reliable is Tricker, , op. cit. (3)Google Scholar, though even he has Ampère doing too much ‘realizing’ (cf. p. 27). The most sophisticated and successful account of Ampère's electrodynamics, though somewhat deficient in historical detail, is Merleau-Ponty, Jacques, Leçons sur la genèse des théories physiques: Galilée, Ampère, Einstein, Paris, 1974, pp. 69–112.Google Scholar

¹² With this reservation, Williams's account of Ampère's views on the existence of a real world of noumena behind the phenomena is good; see DSB, op. cit. (3), pp. 441–2.Google Scholar

¹³ Read on 27 March 1815 and published as ‘Demonstration d'un théorème d'où l'on peut déduire toutes les lois de la réfraction ordinaire et extraordinaire’, Mémoires de la Classe des sciences mathématiques et physiques de l'Institut de France, 1813–1815, 14, (published 1818), 235–48Google Scholar. On this paper see also n. 50, below.

¹⁴ Ampère, , ‘Essai d'une classification naturelle pour les corps simples’, Annales de chimie et de physique, 1816, 1, 295–308, 373–94Google Scholar; 1816, 2, 5–32, 105–25. On 24 January 1820 he presented to the Academy a mathematics memoir which had been written during 1818 and separately published in 1819: ‘Mémoire contenant l'application de la théorie exposée dans le XVII^e cahier du Journal de l'Ecole polutechnique, á l'intégration des équations aux différentielles partielles du premier et du second ordre’, Journal de l'École royale polytechnique, XVIII^e cahier, 1820, 11, 1–188Google Scholar; see also Ampère, 's Correspondance, op. cit. (3), ii, 537, 539, 544, 549–551.Google Scholar

¹⁵ Institut de France, Académie des sciences, Procès-verbaux des séances de l'Académie tenues depuis la fondation de l'Institut jusqu'au mois d'août 1835, 10 vols., Hendaye, 1910–1922, ii, 611, 616, 662–3Google Scholar; iii, 28, 88–90, 183, 325–7; v, 362, 398–400, 406, 417–9. Charles Bossut died on 14 January 1814.

¹⁶ On Ampère's attitude toward mathematics see his Correspondance, op. cit. (3), i, 133–5, 225, 275, 281–2, 304–5Google Scholar; ii, 459, 470, 483, 486, 487; iii, 855.

¹⁷ Arago, , op. cit. (4), 34–5Google Scholar. On these connexions see Picavet, François, Les idéologues: essai sur l'histoire des idées et des théories scientifiques, philosophiques, religieuses, etc., en France depuis 1789, Paris, 1891Google Scholar (reprinted Hildesheim & New York, 1972), esp. pp. 467–76. Crosland noted that Ampère was associated with the Société d'Auteuil rather than the Sociéte d'Arcueil; see Crosland, Maurice, The Society of Arcueil: a view of French science at the time of Napoleon I, London, 1967, p. 90CrossRefGoogle Scholar. Herivel noted Ampère's ‘somewhat uncertain reputation’ prior to his work in electrodynamics, but identified only Ampère's interests in mathematics and chemistry; see Herivel, , ‘Ampère: pioneer of electrodynamics’, Endeavour, 1975, 34, 34–7 (35).CrossRefGoogle Scholar

¹⁸ On Ampère's work in chemistry see especially Levere, Trevor H., Affinity and matter: elements of chemical philosophy, 1800–1865, Oxford, 1971, pp. 113–22Google Scholar; Sadoun-Goupil, Michelle, ‘Esquisse de l'oeuvre d'Ampère en chimie’, Revue d'histoire des sciences et des leurs applications, 1977, 30, 125–41CrossRefGoogle Scholar; and Mauskopf, Seymour, ‘The atomic structural theories of Ampère and Gaudin: molecular speculation and Avogadro's hypothesis’, Isis, 1969, 60, 61–74CrossRefGoogle Scholar. Ampère's connexions with Davy need tobe worked out in greater detail. His correspondence with Davy, begun in 1810, was by far his most important from a scientific standpoint before that with Faraday and Auguste de La Rive after 1820, and Ampère drew particular inspiration from his personal contacts with Davy during the latter's stay in Paris during November and December 1813.

¹⁹ Ampère, , ‘Essai’ op. cit. (14), 1, 383–4Google Scholar. Brown recognized the general importance of Ampère's chemical sympathies, but there are serious difficulties with his claim that Ampère was originally a defender of the ‘electrostatic theory’ of the pile and that his main interest gradually shifted from the pile to the ‘reunions’ in the wire; see Brown, , op. cit. (3), pp. 84, 86Google Scholar. Ampère was never particularly interested in the pile.

²⁰ Ampère, , ‘Lettre de M. Ampère á M. le comte Berthollet, sur la détermination des proportions dans lesquelles les corps se combinent d'après le nombre et la disposition respective des molécules dont leurs particules integrantes sont composées’, Annales de chimie, ou recueil de mémoires concernant ta chimie et les arts qui en dépendent, et spécialement la pharmacie, 1814, 90, 43–86Google Scholar; and ‘Démonstration de la relation découverte par Mariotte, entre les volumes des gaz et les pressions qu'ils supportent á une même température’ (read 24 January 1814), ibid., 1815, 94, 145–60.

²¹ Ampère, undated letter to Roux-Bordier, wrongly dated ‘end of February 1806’ by de Launay, , Correspondance, op. cit. (3), 1, 299Google Scholar. Ampère's mention of a certain ‘Morosini’ who magnetized steel needles by exposing them to ultraviolet rays can only have referred to the work of Domenico Morishini, published in France as ‘Mémoire sur la force magnétisante du bord extrême du rayon violet; lu á l'Académie des Lincei á Rome, le 10 septembre 1812’ Journal de physique, de chimie, d'histoire naturelle et des arts, 1813, 76, 208–15Google Scholar, reprinted from Bibliothèque britannique, 1813, 52, 21–35.Google Scholar

²² This point was made by Levere, , op. cit. (18), p. 115.Google Scholar

²³ Arago came back from Geneva with a French translation of Oersted's paper prepared by Marc-Augustine Pictet; only since then had other Parisian scientists received copies directly from Oersted; see Annales de chimie et de physique, 1820, 14, 417Google Scholar. On 1 September 1820 a Danish correspondent of Oersted's who had been in Paris seven weeks wrote that he had not yet been able to find a published account of Oersted's discovery; see Henrik Gerner von Schmidten's letter of that date to Oersted in Ørsted, Mathilde (ed), Breve fra og til Hans Christian Ørsted, 2 vols., Kjøbenhavn, 1870, ii, 8–9.Google Scholar

²⁴ Dulong, Pierre-Louis, letter of 2 10 1820Google Scholar to Berzelius, Jons Jacob, in Söderbaum, H. G. (ed.), Jac. Berzelius bref, 6 vols., + 3 supplements Uppsala, 1912–1961, ii, part I, 18.Google Scholar

²⁵ Ampère, , letter of 21 02 1821Google Scholar to Roux-Bordier, , in Correspondance, op. cit. (3), ii, 566Google Scholar; quoted by Brown, , op. cit. (3), p. 90.Google Scholar

²⁶ Marcet, Alexandre, letter of 15 09 1820Google Scholar to Berzelius, from Geneva, in Berzelius bref, op. cit. (24), i, part III, 210.Google Scholar

²⁷ Ampère, , letter of 25 09 1820Google Scholar to his son, in Correspondance, op. cit. (3), ii, 561–2Google Scholar. For a preliminary attempt to place Ampère's response within a theoretical/typological context, see Caneva, K. L., ‘What should we do with the monster? Electromagnetism and the psychosociology of knowledge’, Sociology of the sciences: a yearbook, 1980, 4, forthcoming.Google Scholar

²⁸ Frankel correctly noted that ‘Ampère's protestations of Newtonianism, which have received much attention in the secondary literature, were largely a response to Biot's criticism’; see Frankel, Eugene, ‘Jean Baptiste Biot: the career of a physicist in nineteenth century France’, Princeton University doctoral dissertation, 1972, p. 345.Google Scholar

²⁹ Characterizations of this programme are given by Crosland, , op. cit. (17), pp. 245–62, 299–308Google Scholar; Fox, Robert, ‘The Laplacian programme for physics’, Boletin de la Academia Nacional de Ciencias de la República Argentina, 1970, 48, 429–37Google Scholar; idem, ‘The rise and fall of Laplacian physics’, Historical studies in the physical sciences, 1974, 4, 89–136Google Scholar (91–2); and Frankel, E., ‘J. B. Biot and the mathematization of experimental physics in Napoleonic France,’Google Scholaribid., 1977, 8, 33–72 (46–7). For a discussion of the methodological positions assumed by Laplace, Biot, Fresnel, Poisson, Fourier, and Ampère, see Caneva, K. L., ‘Conceptual and generational change in German physics: the case of electricity, 1800–1846’, Princeton University doctoral dissertation, 1974Google Scholar; to be published by Arno Press, pp. 331–63. The ‘Newtonianism’ of Laplace and Biot included a belief in the possibility of the non-hypothetical inductive derivation of certain fundamental physical laws—such as that of universal gravitation—directly from the phenomena. See also Hahn, Roger, Laplace as a Newtonian scientist, Los Angeles, 1967.Google Scholar

³⁰ Fox, R., ‘The background to the discovery of Dulong and Petit's law’, British journal for the history of science, 1968–1969, 4, 1–22 (1)CrossRefGoogle Scholar; idem, The caloric theory of gases from Lavoisier to Regnault, Oxford, 1971, pp. 227–80Google Scholar; idem, ‘The rise and fall’, op. cit. (29), pp. 109–10.Google Scholar

³¹ These last five individuals were identified as the chief anti-Laplacians by Fox, , Caloric theory, op. cit. (30), p. 227Google Scholar; idem‘The rise and fall’ op. cit. (30), p. 110Google Scholar; and by Ravetz, Jerome R., Scientific knowledge and its social problems, Oxford, 1971, p. 227Google Scholar. To this group Frankel, E. added Ampère; see ‘Corpuscular optics and the wave theory of light: the science and politics of a revolution in physics’, Social studies of science, 1976, 6, 141–84(172)CrossRefGoogle Scholar. Frankel's work is particularly sensitive to the importance of personal clashes. Fourier certainly experienced the opposition of the Laplacians, but whether or not he shared the physical world view common to the others is an open question.

³² Crosland, , op. cit. (17), pp. 225, 322–3, 331–4Google Scholar. According to Crosland, Arago's ties with the Arcueil group were weaker than those of the others; see ibid., p. 316.

³³ Silliman, Robert H., ‘Augustin-Jean Fresnel’, in DSB, op. cit. (3), v, 165–71 (167)Google Scholar; Frankel, , op. cit. (31), p. 158Google Scholar. Fresnel's first diffraction memoir of 15 October 1815 (see n. 47 below) was presented to the Academy on 23 October and referred to Poinsot and Arago, the latter giving a long and favourable report on 25 March 1816; see Procès-verbaux, op. cit. (15), 5, 562Google Scholar; 6, 40. Arago's repon was first published in de Senarmont, Henri, Verdet, Emile, and Fresnel, Léonor (eds.), Oeuvres complètes d'Augustin Fresnel, 3 vols., Paris, 1866–1870, i, 79–87Google Scholar. Fresnel's polarization memoir of 7 October 1816 was referred to Arago and Ampère, ; see Procès-verbaux, 6, 84Google Scholar. Arago's report, not given until 4 June 1821, was printed in Annales de chimie et de physique, 1821, 17, 80–102Google Scholar, and reprinted in Fresnel, 's Oeuvres, i, 553–68Google Scholar. See also n. 35 below.

³⁴ See the contributions of Fresnel, , Arago, , and Biot, to the Annales de chimie et de physique, 1821, 17, 80–102Google Scholar (Arago), 102–111 (Fresnel), 167–196 (Fresnel), 225–258 (Biot), 258–273 (Arago), 312–315 (Fresnel), and 393–403 (Fresnel). On this feud see Frankel, , op. cit. (31), pp. 165–8Google Scholar, and [Libri, Guillaume], ‘Lettres à un Américan sur l'état des sciences en France. I. L'Institut. II. L'Institut. III. M. Poisson’, Revue des deux mondes (Paris), 1840, 21, 789–818Google Scholar (798–9); 1840, 22, 532–54; 1840, 23, 410–37. Libri noted that Laplace had taken sides against Arago. Schmidten reported that the battle between Biot and Arago during the summer of 1821 had led to the formation of two parties, the ‘Ultra’ and the ‘Libérale’, defending respectively the old and new theories of light, with Laplace belonging to the former; see Schmidten's letter of 21 March 1822 to Oersted from Paris, in Oersted, 's Breve, op. cit. (23), ii, 23.Google Scholar

³⁵ Arago, and Petit, Alexis-Thérèse, ‘Sur les puissances réfractives et dispersives de certaines liquides et des vapeurs qu'ils forment’ (read at the Academy on 11 December 1815), Annales de chimie et de physique, 1816, 1, 1–9Google Scholar. On the relevance of this work to the authors' support of Fresnel's wave theory, see Fox, , Caloric theory, op. cit. (30), pp. 202, 233–4Google Scholar. Fox elsewhere remarked that Dulong and Petit were among Fresnel's earliest converts, though hard evidence for this seems to be wanting (especially for Dulong) other than the probable intended support for Fresnel implied by Arago's and Petit's work; see Fox, , ‘The background’ (30), p. 21Google Scholar. Petit, who died in 1820 at the age of 28, had married Arago's sister in November 1814; see Fox, , Caloric theory, p. 233.Google Scholar

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³⁷ Arago, , op. cit. (4), p. 69Google Scholar. On Laplace's opposition to both Fresnel and Ampère, see an undated letter of Ampere's in his Correspondance, op. cit. (3), ii, 680Google Scholar. Though de Launay said the letter was to Davy, a comparison with letters from Ampère, to Faraday, of 3 07 1825Google Scholar and from Faraday, to Ampère, of 17 11 1825Google Scholar suggests that it was in fact written to Faraday after Ampère's receipt of the second-of these; see Ampère, 's Correspondance, ii, 678–9Google Scholar, and Williams, L. Pearce (ed.), The selected correspondence of Michael Faraday, 2 vols,. Cambridge, 1971, i, 153–4Google Scholar. Frankel suggested that Ampère's belief in an ether further alienated Biot from his theory; see op. cit. (28), p. 341.

³⁸ Biot, Jean-Baptiste, Traité de physique expérimentale et mathématique, 4 vols., Paris, 1816Google Scholar, long sections of which were taken over virtually unchanged into his Précis élémentaire de physique expérimentale, 2 vols., Paris, 1817Google Scholar; 2nd edn., 1821; 3rd edn., 1824. See, for example, his handling of static electricity (Traité, ii, 211Google Scholar; Précis, 3rd edn., i, 466Google Scholar), and magnetism (Précis, 3rd edn., ii, 2Google Scholar); at this last, after running through some of the basic phenomena of magnetism, he asked: ‘What is the nature of the principle which produces these phenomena? We do not know. But whatever it might be we will define it, for the sake of conciseness, by the name of magnetism; it is thus that one calls electricity the unknown principle of the electrical phenomena, and caloric the no less unknown principle of heat’.

³⁹ Mérimée, Léonor, letter of 6 03 1817Google Scholar to Fresnel, , in Fresnel, 's Oeuvres, op. cit. (33), ii, 842.Google Scholar

⁴⁰ Cf. Frankel, , op. cit. (31), pp. 154–68Google Scholar. Arago said that he and Ampère had been friends for thirty years—Ampère died in 1836—and that they had had an intimate correspondence which Ampère had asked him to destroy; see Arago, , op. cit. (4), pp. 92, 100.Google Scholar

⁴¹ Littré, , op. cit. (4), p. 433Google Scholar. Many suggestive leads can be found in Friedman, Robert Marc, ‘The creation of a new science: Joseph Fourier's analytical theory of heat’, Historical studies in the physical sciences, 1977, 8, 73–99.CrossRefGoogle Scholar

⁴² See especially Rosmorduc, Jean, ‘Ampère et l'optique: une intervention dans le débat sur la transversalité de la vibration lumineuse’, Revue d'histoire des sciences et de leurs applications, 1977, 30, 159–67CrossRefGoogle Scholar. Williams noted Ampère's belief in an ether and his friendship with Fresnel, although he missed the role the ether played for Ampère, who did not simply mathematize a physical model; see Williams, , ‘Ampère's electrodynamic molecular model’, op. cit. (3), p. 119Google Scholar, and idem., Michael Faraday, op. cit. (3), pp. 148, 455.Google Scholar

⁴³ Mérimée, Léonor, letter of 5 08 1811Google Scholar to Fresnel, , in Fresnel, 's Oeuvres, op. cit. (33), ii, 811.Google Scholar

⁴⁴ Silliman, , in DSB, op. cit. (33), p. 167Google Scholar; idem, Fresnel and the emergence of physics as a discipline’, Historical studies in the physical sciences, 1974, 4, 137–62Google Scholar (147). These connexions badly need tobe worked out.

⁴⁵ Fresnel, , letter of 5 07 1814Google Scholar to his brother, in Fresnel, 's Oeuvres, op. cit. (33), ii, 820.Google Scholar

⁴⁶ Ibid., pp. 821–2.

⁴⁷ Fresnel, , ‘Premier mémoire sur la diffraction de la lumière, où l'on examine particulièrement le phénomène des franges colorées que présentent les ombres des corps éclairés par un point lumineux’Google Scholar, in Fresnel, ibid., i, 9–33 (12). See also his covering letter to Delambre of 15 October 1815 (ibid., pp. 9–10), and the supplement of 10 November 1815, ‘Complément au mémoire sur la diffraction’, ibid., pp. 41–60 (59), where he again presented heat and light as vibrations of caloric and discussed a few significant chemical reactions.

⁴⁸ Silliman, , in DSB, op. cit. (33), p. 167Google Scholar; see also idem, ‘Fresnel and the emergence’, op. cit. (44), pp. 146–9.Google Scholar

⁴⁹ Fresnel, , letter of 3 11 1814Google Scholar to his brother, in Fresnel, 's Oeuvres, op. cit. (33), ii, 829Google Scholar; Mérimée, Léonor, letter of 20 12 1814Google Scholar to Fresnel, ibid., p. 830.

⁵⁰ Ampère, , letter of 19 05 1816Google Scholar to Ballanche, , in Ampère's Correspondance, op. cit. (3), ii, 511Google Scholar; Fresnel, , letter of 19 07 1816Google Scholar to his brother, in Fresnel, 's Oeuvres, op. cit. (33), ii, 835Google Scholar. Costabel claimed that Ampère had supported the wave theory in his memoir of 27 March 1815 on the laws of refraction; see Costabel, Pierre, ‘L'activité scientifique d'Ampère’, Revue d'histoirt des sciences et de leurs applications, 1977, 30, 105–12CrossRefGoogle Scholar (108). This is not borne out by an examination of the memoir in question (see n. 13 above) and is contradicted by a later statement of Ampère's; see Ampère, , ‘Mémoire sur la détermination de la surface courbe des ondes lumineuses dans un milieu dont l'élasticité est différent suivant les trois directions principales, c'est-à-dire celles où la force produite par l'élasticité a lieu dans la direction même du déplacement des molécules de ce milieu’ (read 26 08 1828), Annales de chimie et de physique, 1828, 39, 113–45(114)Google Scholar, quoted by Rosmorduc, , op. cit. (42), p. 116.Google Scholar

⁵¹ Arago, , op. cit. (4), p. 103Google Scholar. If Arago's remark is correct, it is noteworthy that Ampère valued his theory of magnetism over his mathematical law for the interaction between current elements.

⁵² MS note of 30 August 1816, in Fresnel, 's Oeuvres, op. cit. (33), i, 394.Google Scholar

⁵³ Mérimée, Léonor, letter of 6 03 1817Google Scholar to Fresnel, in ibid., ii, 841–2. On 15 September 1820 Alexandre Marcet wrote to Berzelius that ‘Arago also demonstrated in Geneva a curious experiment on light which is considered to be a great triumph for Messieurs les ondulateurs at the expense of the poor émissionaires who are loosing ground every day’; see Berzelius bref, op. cit. (24), i, 211.Google Scholar

⁵⁴ Ampère, , letter of 25 09 1820Google Scholar to his son, in Ampère, 's Correspondance op. cit. (3), ii, 562Google Scholar. On 6 November 1820 Ampère deposited a sealed note for Fresnel with the secretary of the Academy, then asked for it to be opened and read; see Procès-verbaux, op. cit. (15), 7, 100Google Scholar. Fresnel, 's ‘Note sur des Essais ayant pour but de décomposer l'eau avec un aimant’ was published in Annales de chimie et de physique, 1820, 15, 219–22Google Scholar, reprinted in Fresnel, 's Oeuvres op. cit. (33), ii, 673–6.Google Scholar

⁵⁵ Ampère, , ‘Exposé sommaire des nouvelles expériences électro-magnétiques faites par differens physiciens, depuis le mois de mars 1821, lu dans la séance publique de l'Académie royale des sciences, de 8 avril 1822’Google Scholar, and ‘Notes sur cet exposé des nouvelles expériences relatives aux phénomènes produits par l'action électro-dynamique, faites depuis le mois de mars 1821’, in Ampère, , Recueil d'observations électro-dynamiques, contenant divers mémoires, notices, extraits de lettres ou d'ouvrages périodiques sur les sciences, relatifs à l'action mutuelle de deux courans électriques, à celle qui existe entre un courant électrique et un aimant ou le globe terrestre, et à celle de deux aimons l'un sur l'autre, Paris, 1822 [–3], 199–206, 207–36Google Scholar (214–15). This ‘Exposé’ was originally published as ‘Notice sur les nouvelles expériences électro-magnétiques faites par différens physiciens, depuis le mois de mars 1821, lue dans la séance publique de l'Académie royale des sciences, le 8 avril 1822’, Journal de physique, de chimie, d'histoire naturelle et des arts, 1822, 94, 61–6Google Scholar. Three pages of the ‘Notes’ are translated in my Appendix, above. They probably date from July or August 1822.

⁵⁶ See two autograph notes by Fresnel found among Ampère, 's papers, ‘Comparaison de la supposition des courants autour de l'axe avec celle des courants autour de chaque molécule’Google Scholar, and ‘Deuxième note sur l'hypothèse des courants particulaires’, in Collection de mémoires relatifs à la physique, publiés par la Société française de physique, vols, ii–iiiGoogle Scholar: ‘Mémoires sur l'électrodynamique’, Paris, 1885–1887, ii, 141–3, 144–7Google Scholar. The second of these bore no due in MS, but was dated 5 June 1821. See also the editor's footnote, ibid., p. 140, and the ‘Note sur deux memoires lus par M. Ampère à l'Académie royale des sciences, le premier dans la séance du 26 décembre 1820; le second dans les séances des 8 et 15 janvier‘, Journal de physique, de chimie, d'histoire naturelle et des arts, 1821, 92, 160–5Google Scholar (163). Ampère's first public discussion of molecular currents was on 15 January 1821.

⁵⁷ Fresnel, , ‘Considérations mécaniques sur la polarization de la lumière’, Annales de chimie et de physique, 1821, 17, 179–96Google Scholar (179; cahier of June); reprinted in Fresnel, 's Oeuvres, op. cit. (33), i, 629–45Google Scholar (629–30); quoted by Rosmorduc, , op. cit. (42), 166–7.Google Scholar

⁵⁸ Ampère, , letter of 12 02 1812Google Scholar to Bredin, in Ampère, 's Correspondance op. cit. (3), ii, 398.Google Scholar

⁵⁹ Ampère, , letter of 26 08 1812Google Scholar to Davy, in ibid., p. 417.

⁶⁰ Dulong, , letter of 5 08 1816Google Scholar to Ampère, quoted in English translation in Pierre Lemay and Oesper, Ralph E., ‘Pierre Louis Dulong, his life and work’, Chymia: annual studies in the history of chemistry, 1948, 1, 171–90 (175–6).Google Scholar

⁶¹ Ibid., p. 177.

⁶² Dulong, , letter of 15 01 1820Google Scholar to Berzelius, , in Berzelius Bref, op. cit. (24), ii, 12Google Scholar. Substantial portions of this letter are quoted in Fox, , ‘The background’ op. cit (30), pp. 13, 181Google Scholar, and in idem, Caloric theory, op. cit. (30), p. 244.Google Scholar

⁶³ Ibid., pp. 13–14; also quoted by Fox.

⁶⁴ Oersted, , ‘Sur la propagation de l'électricité’ Journal de physique, de chimie, d'histoire naturelle et des arts, 1806, 62, 369–75 (371, 372).Google Scholar

⁶⁵ Oersted, , Recherches sur l'identité des forces chimiques et électriques, Paris, 1813Google Scholar. This was a translation by Serres, Marcel de of Ansicht der chemischen Naturgesetze, durch die neueren Entdeckungen gewonnen, Berlin, 1812Google Scholar; reprinted in Oersted, , Naturvidenskabelige Skrifter, ed. by Meyer, Kirstine, 3 vols., København, 1920, ii, 35–169Google Scholar. On the book's purpose see also the notice (by Oersted?), ‘Ansicht der chemischen Naturgesete [sic], durch die neuern Entdeckungen gewonnen,… c'est-à-dire, considérations sur les lois chimiques de la nature, fondées sur les nouvelles découvertes’, Journal de physique, de chimie, d'histoire naturelle et des arts, 1813, 76, 233–7 (233; cahier of March).Google Scholar

⁶⁶ Oersted, , Recherches, op. cit. (65), p. 130Google Scholar; this portion was reprinted in the extract made by Jean-Claude Delamétherie, ‘Des forces électriques considérées comme des forces chimiques’, Journal de physique, de chimie, d'histoire naturelle et des arts, 1814, 78, 338–74Google Scholar (341). See also the notice in the Journal de physique cited in n. 65, above, p. 234.

⁶⁷ Oersted, , Recherches, op. cit. (65), pp. 209–11Google Scholar. For an extensive discussion of Oersted's conception of light see Mayer, Kirstine, ‘The scientific life and works of H. C. Ørsted’Google Scholar, in Oersted, 's Skrifter, op. cit. (65), i, pp. xi–clxvi (liv–lxi).Google Scholar

⁶⁸ See n. 10, and the Appendix, above. Cf. Ampère's letter to Albert van Beek, written between 12 January and 27 March 1822: ‘M. Oersted has regarded the composition and decomposition of electricity, which I have designated by the name of electric currents, as the unique cause of heat and light, that is of the vibrations of the fluid diffused through all space and which, according to the hypothesis generally adopted of two electric fluids, one cannot but consider as the combination of these two fluids in die proportion where they mutually saturate each other. This opinion of the great physicist, to whom we owe the first experiments on the mutual action of conducting wires and magnets, accords perfectly with the totality of the phenomena…’; ‘Réponse’, op. cit. (4), pp. 449–50.Google Scholar

⁶⁹ Cf. Oersted, , Recherches, op. cit. (65), pp. 78–9, 107–10, 130Google Scholar with Oersted, , Ansicht, op. cit. (65), pp. 81, 112–15, 140, 254–6Google Scholar. The French translation eliminated all talk of the Kantian construction of matter out of space-filling attractive and repulsive forces. In any event, Ampère's interest in Kant would have made Oersted's way of thinking more accessible to him than it apparently was to most of his French contemporaries, who would have nothing that smacked of German mystification.

⁷⁰ Missing from the German original, for example, was the claim that the dynamical theory of heat is ‘based on a law drawn from experience’; see Oersted, , Recherches, op. cit. (65), p. 200Google Scholar, compared with Oersted, , Ansicht, op. cit. (65), p. 211Google Scholar; the former is quoted in the extract published in the Journal de physique, op. cit. (66), p. 374Google Scholar. See also the entire preface added to the French edition.

⁷¹ See n. 66, above. Another possible source of Ampère's acquaintance with Oersted's views is the French translation of Davy's Elements of chemical philosophy, which included a précis of Oersted's Ansicht der chemischen Naturegesetze which stressed the unity of forces and mentioned the undulatory propagation of electricity; see Davy, Homfrede, Elémens de philosophie chimique, trans, by Van Mons, Jean-Baptiste, 2 vols., Paris & Amsterdam, 1813, i, 211–18Google Scholar. On Ampère's connexions with Davy, see n. 18, above.

⁷² de Blainville, Henri-Marie-Ducrotay, letter of 3 11 1820Google Scholar to Oersted, , in Harding, Marius Christian (ed.), Correspondance de H. C. Örsted avec divers savants, 2 vols., Copenhague, 1920, ii, 271.Google Scholar

⁷³ Ampère asserted that Oersted had nowhere announced the identity of the magnetic and galvanic fluids ‘dans tout ce que nous avons de lui’; see his letter of 14 November 1820 to Jean-Hachette, Nicolas-Pierre, in Ampère's Correspondance, op. cit. (3), iii, 906Google Scholar. Ampère seems to have supplied Hachette with some of the information contained in the latter's note, ‘Sur les expériences électromagnétiques de MM. Oersted et Ampère’, Journal de physique, de chimie, d'histoire naturelle et des arts, 1820, 91, 161–6Google Scholar, which was received by the Academy on 27 November 1820; see Procès-verbaux, op. cit. (15), 7, 103Google Scholar. On p. 163 Hachette says that de Serres’ translation of Oersted's book appeared in 1807; this was probably the source of François-Pierre-Nicholas Gillet de Laumont's similar error in [de Laumont, Gillet and Ampère, ], ‘Note sur les expériences électro-magnétiques de MM. Oersted, Ampère et Arago, relatives à l'identitè de l'aimant avec l'électricité’, Annales des mines, 1820, 5, 535–58Google Scholar (535). This published misinformation may have contributed to Ampère's own confusion, as when he referred in 1821 to Oersted's book as having appeared ‘more than 15 years ago’; see his letter of 21 February 1821 to Roux-Bordier, , in Ampère's Correspondance, ii, 567Google Scholar. Perhaps he was also confused by the date of Oersted, 's 1806 paper, op. cit. (64)Google Scholar. This mistake of Ampère's presents a problem for my argument that he was personally acquainted with Oersted's book, but the evidence for that point still seems to me strong.

⁷⁴ See n. 72, above. Oersted reported during his third trip to Paris diat Chevreul was one of Arago's best friends; see Oersted, 's letter of 12 02 1823Google Scholar to his wife, in Oersted, 's Breve op. cit. (23), ii, 48Google Scholar. Crosland said that Chevreul ‘had crossed swords with the Arcueil group’, and noted that when Davy visited Paris in 1813 ‘he received most attention not from the Arcueil group but from men on the fringe of French science such as Ampère, Clément and Chevreul’; Crosland, , op. cit. (17), pp. 168, 323Google Scholar. A paper of Chevreul's on the relationship between mind and muscular movement was written in the form of a letter to Ampère, and attests to their long-term common interest in this and other questions of philosophical import; see Chevreul, Michel-Eugène, ‘Lettre à M. Ampère sur une classe particulière de mouvemens musculaires’, Revue des deux mondes (Paris), 1833, 2, 258–66.Google Scholar

⁷⁵ Oersted, , letter of 25 02 1813Google Scholar to his brother, in Oersted, 's Breve, op. cit (23), i, 312Google Scholar. Chevreul mentioned the book in a letter of 13 January 1819 to Oersted; see Oersted, 's Correspondance, op. cit. (72), ii, 294Google Scholar. In 1818 Chevreul gave an extensive and very favourable discussion of Oersted's and Ampère's systems of chemical classification in the article ‘Corps. (Chim.)’ in Cuvier, Frédéric-Georges (éd.), Dictionnaire des sciences naturelles, 61 vols., Strasbourg & Paris, 1816–1845, x, 511–39Google Scholar (530–2, 532–8, respectively).

⁷⁶ Referring explicitly to Arago and Ampère, Schmidten recorded his impression from Paris that those who best appreciated Oersted's ideas were those who sought unity in the phenomena of chemistry, electricity, light, and heat; see Schmidten's letter of 21 March 1822 to Oersted, in Oersted, 's Breve, op. cit. (23), ii, 23–4.Google Scholar

⁷⁷ Agassi, for example, explicitly rejected the possibility that Ampère had anything to do with Oersted's speculative belief in the unity of forces; see Agassi, , op. cit. (3), pp. 21–2.Google Scholar

⁷⁸ Ampère, , ‘Notes’, op. cit. (55), pp. 213–16.Google Scholar