John Herschel's Cosmology

1. The principal biography of Herschel John is The shadow of the telescope by Buttmann Günther (New York, 1970; first published in German in 1965); this has an extènsive bibliography. Important manuscript material is now available in print in Evans D. S., et al. (eds), Herschel at the Cape: Diaries and correspondence, 1834–1838 (Austin, Texas, 1969), and Warner Brian and Warner Nancy, Maclear and Herschel: Letters and diaries at the Cape of Good Hope 1834–1838 (Rotterdam, 1984). Biographical essays are of course to be found in Dictionary of national biography (by Agnes M. Clerke) and Dictionary of scientific biography (by David S. Evans).

2. “Your highly prized letter of the 13th May having been addressed to me in ‘London’ without any more particular locale, lost some time in reaching me…”, Herschel John to Steinheil K. A., 16 June 1842 (photocopy in present writer's possession).

3. Buttmann, The shadow (ref. 1), 102–3.

4. Ibid., 56, quoting Herschel John to Brougham Lord, summer or autumn 1827, copy in possession of Royal Society.

5. The same point is made by his younger contemporary and great admirer, Richard A. Proctor, who in an obituary essay writes: “The literary merits of his writing are certainly not exceptionally great. His style is often ponderous, and not unfrequently far from clear. Nor can it be said that he has successfully expounded the difficulties dealt with in his treatises” (Proctor R. A., “Sir John Herschel”, English mechanic for 19 May 1871, reprinted in his Essays on astronomy (London, 1872), 1–7, pp. 6–7).

6. Occasional sheets, marked for destruction, survive among the Herschel MSS in the possession of the Royal Astronomical Society.

7. Herschel John to Baily Francis, 12 February 1828 (copy in possession of Royal Society; cited by Buttmann, The shadow, 49).

8. “Of the reverence with which the younger Herschel regarded the noble labours and the grand conceptions of his father it is perhaps needless to speak. He has, indeed, been blamed, by those who misunderstood his disposition, for carrying that reverence to excess, insomuch that one writer has not scrupled to speak of the manner in which Sir John Herschel regarded the instruments his father had employed as approaching in its nature to idolatry. Altogether denying the justice of such views as these, we must yet recognise the fact that if any theories could have so far found favour in Herschel's sight as to cause him to forget the rules which he had laid down for his own guidance, and to seek rather for evidence confirming those theories than for experiments by which their value might be tested, it would have been to his father's theories respecting the constitution of the universe that he would have been disposed to extend this indulgence” (Proctor Richard A., “Sir John Herschel as a theorist in astronomy”, The St Paul's magazine for June 1871, reprinted in Essays in astronomy (ref. 5), 8–28, pp. 16–17).

9. Herschel William, “Account of some observations tending to investigate the construction of the heavens”, Philosophical transactions, lxxxiv (1784), 437–51.

10. Herschel John, Outlines of astronomy (London, 1849, and numerous later editions; hereafter: Outlines (1st edn unless otherwise specified)), articles 785–6; reprinted from the same typesetting in later editions, including the posthumous edition of 1881. Herschel only slightly modifies the wording of the account given earlier in his A treatise on astronomy (London, 1833; 2nd edn, London, 1851; hereafter: Treatise (1st edn unless otherwise specified)), articles 585–6.

11. Herschel John, Results of observations made during the years 1834, 5, 6, 7, 8 at the Cape of Good Hope; being a completion of a telescopic survey of the whole surface of the visible heavens, commenced in 1825 (London, 1847; hereafter: Cape Observations).

12. See ref. 10 above.

13. Ibid.

14. Including Russian, Chinese and Arabic.

15. For an account of this, see Hoskin Michael, William Herschel and the construction of the heavens (London, 1963), chap. 2: “Double stars and the motion of the Sun”.

16. Herschel John and South James, “Observations of the apparent distances and positions of 380 double and triple stars…”, Philosophical transactions, cxiv (1824), pt 3, 1–412.

17. In Philosophical transactions, lxxvi (1786), 457–99; lxxix (1789), 212–55; and xcii (1802), 477–528.

18. Quoted in Herschel JohnMrs, Memoir and correspondence of Caroline Herschel (London, 1876), 259.

19. Herschel John, “Observations of nebulae and Clusters, made at Slough, with a 20-feet reflector, between the years 1825–1833”, Philosophical transactions, cxxiii (1833), 359–506.

20. Herschel J., Outlines, art 1. Cf. Herschel John, A preliminary discourse on the study of natural philosophy (London, 1830), art. 68.

21. Most notably in the second paragraph of his paper “On the construction of the heavens”, Philosophical transactions, lxxv (1785), 213–66: “…if we add observation to observation, without attempting to draw not only certain conclusions, but also conjectural views from them, we offend against the very end for which only observations ought to be made.”

22. Herschel J., Treatise, art. 584.

23. Ibid., 585.

24. Herschel John, “Account of some observations made with a 20-feet reflecting telescope”, Memoirs of the [Royal] Astronomical Society of London, ii (1826), 459–97: Section 3, “An account of the actual state of the Great Nebula in Orion, compared with those of former astronomers”, 487–95.

25. Herschel William, “Astronomical observations relating to the construction of the heavens, arranged for the purpose of a critical examination”, Philosophical transactions, ci (1811), 269–336, p. 271.

26. Herschel J., op. cit. (ref. 24), 488.

27. Ibid.

28. Herschel John, “Observations with a 20-feet reflecting telescope: Third series”, Memoirs of the [Royal] Astronomical Society of London, iii (1829), 177–213, p. 188.

29. Ibid., 189.

30. In the possession of the Royal Astronomical Society: John Herschel MSS, ½ and 1/3.

31. Herschel William, “Account of some observations tending to investigate the construction of the heavens”, Philosophical transactions, lxxiv (1784), 437–51, and “On the construction of the heavens”, ibid., lxxv (1785), 213–66.

32. On this see Hoskin Michael, Stellar astronomy: Historical studies (Chalfont St Giles, Bucks, 1982), Section B.

33. In his 1785 paper cited in ref. 31.

34. Herschel William, “Astronomical observations and experiments, selected for the purpose of ascertaining the relative distances of clusters of stars…”, Philosophical transactions, cviii (1818), 429–70, p. 463: “…when our gages will no longer resolve the milky way into stars, it is not because its nature is ambiguous, but because it is fathomless.” Idem, “Astronomical observations and experiments tending to investigate the local arrangement of the celestial bodies in space…”, Philosophical transactions, cvii (1817), 302–31, art. IX: “…I have now to remark that, although a greater number of stars in the field of view is generally an indication of their greater distance from us, these gages, in fact, relate more immediately to the scattering of stars, of which they give us valuable information….”

35. Quoted from William Herschel's MS observing books in Dreyer J. L. E. (ed.), The scientific papers of Sir William Herschel (2 vols, London, 1912), ii, 657.

36. Herschel J., op. cit. (ref. 19), 497: “But it is evident that all idea of symmetry caused by rotation on an axis must be relinquished, when we consider that the elliptic form of the inner subdivided portion indicates with extreme probability an elevation of that portion above the plane of the rest, so that the real form must be that of a ring split through half its circumference, and having the split portions set asunder at an angle of about 45° each to the plane of the other.”

37. Herschel J., Treatise, art. 624.

38. Cited in ref. 36 above.

39. Herschel J., op. cit. (ref. 19), 496–7.

40. Sweep 184, 4 October 1828.

41. Herschel J., Treatise, articles 585–6.

42. Ibid., art. 624.

43. Herschel J., Treatise, art. 625: “That by far the larger share of them consist of stars there can be little doubt.” Cf. the notes to his 1833 Catalogue, where he remarks: “If a nebula be nothing more than a cluster of discrete stars, (as we have every reason to believe, at least in the generality of cases,)…” (op. cit. (ref. 19), 501).

44. Herschel J., Treatise, art. 617.

45. Ibid., art. 618.

46. Ibid., art. 619.

47. Ibid., art. 619. He had expressed similar views in 1826: Little wisps in the Huygenian region “present, however, no appearance of being composed of small stars, and their aspect is altogether different from that of resolvable nebulae. In the latter we fancy by glimpses that we see stars, or that, could we strain our sight a little more, we should see them. But the former suggests no idea of stars, but rather of something quite distinct from them” (op. cit. (ref. 24), 491).

48. Herschel J., Treatise, art. 620. Similarly, in 1826 he declared: “Its nebulosity is of the most perfectly milky absolutely irresolvable kind, without the slightest tendency to that separation into flocculi above described in the nebula of Orion, nor is there any sort of appearance of the smallest star in the centre of the nipple” (op. cit. (ref. 24): Section 4, “Observations of the nebula in the Girdle of Andromeda”, 495–7, p. 496). In “Observations of Biela's comet”, Memoirs of the Royal Astronomical Society, vi (1833), 99–109, he remarks: “It [the central point] had not, however, the appearance of a star, but seemed more analogous to the central point in some nebulae, such as that in Andromeda, which is probably only nebula much more Condensed than the rest” (p. 107).

49. Herschel J., Treatise, art. 621.

50. Ibid., art. 621.

51. Ibid., art. 621.

52. Ibid., art. 622.

53. Ibid., art. 623.

54. Ibid., art. 616.

55. Ibid., art. 582.

56. Ibid., art. 625.

57. Ibid.

58. Herschel J., op. cit. (ref. 19), 499.

59. Herschel John, “Remarks on a fifth catalogue of double stars”, Memoirs of the Royal Astronomical Society, vi (1833), 74–82, pp. 78–79 (communicated 7 June 1832).

60. Airy G. B., “Address on presenting the honorary medal to Sir J. F. W. Herschel”, Memoirs of the Royal Astronomical Society, ix (1836), 303–12, pp. 304–5.

61. Ibid., 305.

62. Ibid., 305.

63. Ibid., 305.

64. Ibid., 309.

65. On Herschel's period at the Cape, see the works cited in ref. 1. On Caroline's comet-sweeper, see Hoskin M. and Warner B., “Caroline Herschel's comet sweepers”, Journal for the history of astronomy, xii (1981), 27–34.

66. This important letter was publicly read fifteen months later, on 24 August 1836 at the BAAS meeting in Bristol, and quickly published in The Athenaeum ((1836), 627–8). It is reprinted in Hoskin Michael, “Astronomical correspondence of William Rowan Hamilton”, Journal for the history of astronomy, xv (1984), 69–73. Herschel expressed the same opinion of the structure of the Galaxy and the position of the Sun in it in a letter from the Cape to the Italian astronomer G. Plana (see Mossotti O. F., Scritti (Pisa, 1942), i, 294–5; I owe this reference to M. Turchetta and G. Gavazzi).

67. Herschel J., Cape Observations, art. 131.

68. Ibid., art. 109.

69. Ibid., art. 109.

70. Ibid., art. 109.

71. Ibid., art. 111.

72. Ibid., art. 112.

73. Ibid., art. 44: “…at least nine-tenths of the whole nebulous contents of the heavens will be found to belong to this class….”

74. Ibid., art. 121.

75. Ibid., art. 124.

76. Herschel W., op. cit. (ref. 17).

77. Herschel J., Cape Observations, art. 107.

78. Herschel J., Treatise, art. 616.

79. Herschel W., op. cit. (ref. 9), 450. See Plate 2 and the comment by Dewhirst D. W. in Hoskin, op. cit. (ref. 15), 81.

80. Herschel J., Cape Observations, articles 97, 98.

81. Ibid., art. 106.

82. Ibid., art. 106.

83. Ibid., art. 105.

84. See, for example, Shapley Harlow, “Star Clusters and the structure of the universe”, Scientia, xxvi (1919), 269–76, 353–61, and xxvii (1920), 93–101, 185–93.

85. Herschel J., Cape Observations, articles 106–7.

86. Ibid., art. 107.

87. For a discussion of the problem of the Zone of Avoidance, see Hoskin Michael, Stellar astronomy (ref. 32), section C, chap. 3.

88. Cited above, from Herschel's letter of June 1835 (ref. 66).

89. Herschel J., Treatise, art. 624.

90. Cited above, from Herschel's letter of June 1835 (ref. 66).

91. Herschel J., Cape Observations, chap. 4.1: “Of the statistical distribution of stars”.

92. Ibid., art. 314.

93. Ibid., art. 315.

94. Herschel J., Treatise, art. 585.

95. Herschel J., Outlines, art. 785.

96. Herschel J., Cape Observations, art. 321. For the implications of this “subordinate sheet or stratum”, see the draft article published in our Appendix.

97. Ibid., art. 326.

98. Herschel J., Outlines, art. 798.

99. Herschel J., Cape Observations, art. 335.

100. Ibid., art. 336.

101. Herschel J., Outlines, art. 788.

102. Ibid., art. 797, emphasis in original.

103. Ibid., art. 797, emphasis in original.

104. Ibid., art. 797.

105. Ibid., art. 798, emphasis in original.

106. Struve F. G. W., Études d'astronomie Stellaire (St Petersburg, 1847), 67 seq.

107. Herschel J., Outlines, art. 796.

108. Herschel John to Sykes W. H., 12 April 1839, cited by Buttmann, The shadow (ref. 1), 119.

109. A large-scale reproduction of this drawing is in Hoskin Michael, “The first drawing of a spiral nebula”, Journal for the history of astronomy, xiii (1982), 97–101.

110. Herschel John, “An address to the British Association for the Advancement of Science at the opening of their meeting at Cambridge, June 19th, 1845”, reprinted in Herschel John, Essays from the Edinburgh and Quarterly Reviews, with addresses and other pieces (London, 1857), 634–82, pp. 659–60.

111. Ibid., 660–3, emphasis in original.

112. Robinson T. R., “On Lord Rosse's telescope”, Proceedings of the Royal Irish Academy, iv (1848), 119–28: “About fifty nebulae, selected from Sir John Herschel's catalogue, without any limitation of choice but their brightness, were all resolved without exception [emphasis in original]. From this he conceives himself authorized to ask, is there any evidence that nebulous matter has real existence?” (p. 119).

113. Rosse's letter to J. P. Nichol announcing the ‘resolution’ is reprinted by Nichol in his Architecture of the heavens, 10th edn (London, 1850), 112–14.

114. Bond W. C. to Everett Edward, President of Harvard University, 22 September 1847: You Will rejoice with me that the great nebula in Orion has yielded to the powers of our incomparable telescope! This morning, the atmosphere being in a favorable condition, at about 3 o'clock the Telescope was set upon the Trapezium in the great nebula in Orion. Under a power of 200 the 5th star was immediately conspicuous; but our attention was very soon absorbed with the splendid revelations made in its immediate vicinity. This part of the nebula was resolved into bright points of light. The number of stars was too great to attempt counting them;—many however were readily located and mapped. The remarkable character of the star θ in the Trapezium was readily recognized with a power of 600. The companion, “Struve's sixth star,” was distinctly separated from its primary, and certain of the stars composing the nebula were seen as double stars under this power. It should be borne in mind, that this nebula and that of Andromeda have been the last strong-holds of the nebular theory; that is, the idea first suggested by the elder Herschel of masses of nebulous matter in process of condensation into systems. The nebula in Orion yielded not to the unrivalled skill of both the Herschels, armed with their excellent reflectors. It even defied the powers of Lord Rosse's three-foot mirror, giving “not the slightest trace of resolvability”: By which term is understood the discerning singly a number of sparkling points. (Cited in Jones B. Z. and Boyd L. G., The Harvard College Observatory (Cambridge, Mass., 1971), 67–68.)

115. Herschel J., Essays (ref. 110), 257–364.

116. Ibid., 287, emphasis in original.

117. Herschel J., Outlines, art. 894, emphasis in original.

118. Herschel J., Essays (ref. 110), 288.

119. Herschel J., Outlines, articles 883–4.

120. Herschel J., “Catalogue of nebulae and Clusters of stars”, Philosophical transactions, cliv (1864), 1–137.

121. Herschel J., Outlines, art. 877.

122. Herschel J., Outlines, 5th edn (London, 1858), art. 877.

123. Herschel J., Outlines, 10th edn (London, 1869), Preface.

124. Herschel John to Proctor R. A., 1 August 1869, reprinted in Proctor, op. cit. (ref. 8), 23; emphasis in original. The complete correspondence is reprinted by Proctor in his Other suns than ours (London, 1887), Appendix (pp. 393–419). The last letter from Herschel is dated 7 February 1871, three months before his death.