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‘O tempera, O magnes!’: A sociological analysis of the discovery of secular magnetic variation in 1634

Published online by Cambridge University Press:  05 January 2009

Stephen Pumfrey
Affiliation:
Department of History, University of Lancaster.

Extract

As sociologists learn more about how scientific knowledge is created, they give historians the opportunity to rework their accounts from a more contextual perspective. It is relatively easy to do so in areas with large theoretical, cosmological or overtly ideological components. It is more difficult, but equally necessary, to open up very empirical accomplishments, and recent sociological analysis of the process of science gives us some interesting insights. This paper employs some of these on the apparently unpromising subject of the ‘discovery of secular magnetic variation’ in 1634 by the Gresham professor Henry Gellibrand.

Type
Research Article
Copyright
Copyright © British Society for the History of Science 1989

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References

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18 See the second part of Section VII below.

19 Seen. 16.

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35 Cardan, J., De Subtilitate Libri XXI, Basle, 1554, p. 215.Google Scholar

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39 Medina, , op. cit. (14)Google Scholar, Arte.

40 Bourne, W., A Regiment for the Sea, LondonGoogle Scholar, 1574, chapter IX. The quotation from the 1576 (2nd) edition is taken from Waters, p. 142.

41 Digges, T., A Perfit Description of the Celestiall Orbs (LondonGoogle Scholar, 1576), signature 04r–v.

42 Quoted from Waters, , p. 146.Google Scholar For Bourne see Taylor, , op. cit. (1), Mathematical Practitioners, p. 33Google Scholar; For Borough see Waters, , p. 96.Google Scholar

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46 Ibid.., p. 205.

47 De Magnete, p. 67.Google Scholar

48 Ibid.., pp. 247–248.

49 Gilbert, , op. cit. (14), De Magnete, p. 241.Google Scholar Interestingly, Gilbert, didGoogle Scholar believe that the earth underwent continuous and major geological changes of the kind that would alter variation. One such was the disappearance of Atlantis. See Gilbert, W., De Mundo nostro Sublunari, Amsterdam, 1651 (reprint edn, Amsterdam, 1965), pp. 282283 and 292293 especially.Google Scholar

50 Gilbert, , op. cit. (14), De Magnete, p. 247.Google Scholar

51 Ibid.., Book 4, chapter IX, pp. 251–254.

52 Ibid.., Book 4, chapter XIII, pp. 265–267.

53 Ibid.., pp. 234–5, 254–5, 269.

54 Zilsel, E., ‘The Origins of William Gilbert's Scientific Method’, Journal for the History of Ideas, 1941, 2, pp. 131CrossRefGoogle Scholar; Bennett, J. A., ‘The Mechanics' Philosophy and the Mechanical Philosophy’, History of Science, (1986), 24, pp. 128.CrossRefGoogle Scholar

55 Gilbert, , op. cit. (14), De Magnete, pp. 14, 181.Google Scholar

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57 See notes 45, 46.

58 Wright, , Certaine Errors (1599), p. Mv; 2nd edn (1610), p. 9.Google Scholar

59 I have used the British Library copy, shelf mark 533.k.9. This is in French and bears the date 1603 on the title page but other parts e.g. Books III and IV are dated 1604. According to Waters, , op. cit. (1), Navigation, p.275Google Scholar, other versions existed dated 1602 and written partly in Scots.

60 Nautonnier, , op. cit. (59), Mécometrie, Definitions 6 and 7, pp. 2136, 3744.Google Scholar

61 Ibid.., pp. 21,37.

62 See Fournier, G., Hydrographie, Paris, 1643, pp. 542, 607Google Scholar; Balmer, H., Beitrage zur geschichte der Erkenntnis des Erdmagnetismus, Zurich, 1956, pp. 461462.Google Scholar

63 By Jean Le Tellier in 1631. See Taylor, , op. cit. (12), Havenfinding Art, p. 220.Google Scholar

64 See Nautonnier, , op. cit. (59)Google Scholar, Mécotnetrie, ‘Au Lecteur’, for his self-proclaimed breadth of reading.

65 ‘… les observations de plus grans Pilotes qui ayent este au monde durant le siècle passé’, ibid.., p. 11.

66 Ibid.., p. 14.

67 Ibid.., Au lecteur, p. 1.

68 Ibid.., pp. 66–68, 95–98.

69 ‘si quelqu'un veut dire, que le defaut de rondeur en la terre, est cause de la variation de l'eymant, je dy que … il est tout certain et indubitablement resolu, que la terre est ronde … la profondeur de la mer et la hauteur des montaignes est si petite, eu esgard a ceste grand machine, que sa rondeur n'en pas difformee.’ Ibid.., pp. 95–6.

70 ‘ne sont presque rien eu esgard au rest d'icelle, ce qui est monstre par Guillaume Gilbert au dernier chapitre du premier livre de l'eymant,’ Ibid.., p. 96.

71 Gilbert, , op. cit. (14), De Magnete, p. 235.Google Scholar

72 Cabeo, N.Philosophia Magnetica, Ferrara, 1629, p. 76.Google Scholar Although Cabeo's description might appear to be a thought experiment, he instructed the reader ‘tum vero caera, aut alia simile re reple cavitates, quas fecisti:

73 Gilbert, op. cit. (14), De Magnete, p. 232.Google Scholar

74 Gilbert, , op. cit. (14), De Magnate, p. xli.Google Scholar

75 An appendix to Blundeville, T., The Theoriques of the Seven Planets, London, 1602.Google Scholar In ‘A short Appendix annexed to the former Treatise by Edward Wright, at the motion of the right Worshipful M. Doctor Gilbert’ Wright wrote ‘that (according to M. Blundeviles earnest request) this table following should be hereunto adjoined, which M. Henry Briggs … calculated.’ See p. 29.

76 London, 1609.

77 Taylor, , op. cit. (1), Mathematical Practitioners, p. 339.Google Scholar

78 Linton, , op. cit. (76), Newes, p. 15.Google Scholar

79 Ibid.., p. 12.

80 Barlow first circulated his Magnetical Advertisments as a manuscript in 1609. Ridley later commented that the Dedicatory Epistle said that Barlow's stimulus had been the desire to refute a French work called ‘Niccometria Magnetica [sic]’ by one Gulielmus Nantonierus [sic].

81 Taylor, , op. cit. (1), Mathematical Practitioners, p. 176.Google Scholar

82 Linton, , op. cit. (76), Neives, p. ii.Google Scholar

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84 Ibid.., signature Ppr.

85 Waters, , op. cit. (1), Navigation, p. 282. See pp. 282–284.Google Scholar

86 Waters, , op. cit. (1) Navigation, pp. 288, 499.Google Scholar

87 See the third part of Section VII below.

88 Carpenter, N., Geography Delineated Forth in Two Bookes. Oxford, 1625, pp. 5963.Google Scholar On p. 63 Carpenter supported Gilbert and considered that pole theorists ‘laboured with more hope than successe,’ echoing Ridley's taunt.

89 Purchas, S., Purchas His Pilgrims, (2nd edn) London, 1625, Book II, pp. 34.Google Scholar On variation ‘most laborious have beene the paines, most probable (perhaps) the reasons of our Countryman Doctor Gilbert.’

90 See the first two parts of Section VII below.

91 For Alleaume (Aleaume) see Mersenne, M., Correspondence du P. Marin Mersenne Religieux Minime ed. de Waard, C. (15 vols, Paris, 19451983), vol. i, p. 315, and p. 617.Google Scholar

92 Paris, 1611.

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97 Mersenne, , op. cit. (95), Verite, p. 911.Google Scholar ‘on donne un pole particulier a l'aymant, vers lequel il dresse tousiours sa pointe, que plusieurs pensent estre à 23 desgrez, et demy du pole arctique, pres du point ou le circle arctique entrecoupe le premier meridian.’

98 ‘Puisque vous mettez de nouveaux pole pour l'aimant, on pourroit ce semble, inventer quelque nouvelle Geographie, …’ ‘Plusieurs ont en cette pensee, car outre l'essieu, les poles et l'equateur de la guidaymant, Castel-franc a voulu, des demi-circles, des paralleles, un cercle d'attouchement, un autre du Nort, et du sudaymant.’ Ibid.., pp. 916–917.

99 Ibid.., pp. 912–915.

100 ‘Or je vous conseille de ne vous assurer pas tellement sur les tables mecometriques que vous n'observiez vous meme quelle declinaison vous trouverez en chaque lieu.’ Ibid.., p. 929.

101 In his notes on Grandami's magnetic position finding scheme, which employed inclination and declination, he remarked that ‘probandum esset 1 has variari secundum variationem locorum et adhuc sensibiliter, quod falsum jam saepe comperimus.’ Grandami's publication meant that ‘error Castel-franci jam dudum cognitus et amandatus vim de novo recipiet et intensum habebit;’ Mersenne, op. cit. (91), Correspondance, vol. xiii, p. 576.Google Scholar

102 La Charlonye, to Mersenne, , 9 09 1634Google Scholar, Mersenne, , op. cit. (91)Google Scholar, Correspondance, vol. iv, p. 358.Google Scholar

103 Ibid.., vol. ix, p. 252.

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107 Gellibrand, , op. cit. (2), Discourse, p. 16.Google Scholar

108 ‘Tum fuimis omnes in ea sententia ut putaremus ab antiquis peccatum hie fuisse.’ Petit, op. cit. (28), Dissertatio, p. 30.Google Scholar

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110 Gellibrand, , op. cit. (2), Discourse, p. 16.Google Scholar

111 Idem.

112 Ibid.., pp. 16–17.

113 Ibid., p. 17.

114 It is clear from Borough's Discourse and Gunter's Description and Use of the Sector that a basic equal altitude method was used, involving just one needle.

115 See the first and third part of Section VII, and Section VIII.

116 For careful definitions of this and other analytical concepts, see Collins, Harry, ‘The Place of the Core Set in Modern Science: Social Contingency with Methodological Propriety in Science,’ History of Science, (1981), 19, pp. 619.CrossRefGoogle Scholar

117 See notes 156, 157.

118 Quoted from Webster, C., The Great Instauration; Science, Medicine and Reform in England, 1626–1660, London, 1975, p. 358.Google Scholar

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121 Norwood, R., The Sea-Mans Practice, London, 1637 (reprint edn Amsterdam), 1985, p. 108.Google Scholar

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129 Ibid., p. 685; vol. ix, p. 59.

130 Ibid., vol. viii, p. 690.

131 Ibid., p. 705; vol. x, pp. 5, 28, 31, 452; vol. ix, p. 337; Petit, , op. cit. (28), Dissertatio, pp. 2930.Google Scholar

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136 Ibid., p. 262

137 Ibid., p. 404.

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154 Grandami, , op. cit. (93), Nova Demonstratio, p. 73.Google Scholar

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161 This tradition culminated in the four-pole theory of Edmund Halley. He described his theory and the poor state of knowledge about the magnetic poles in Philosophical Transactions, 1683, 12, pp. 208221.Google Scholar