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Observation, working images and procedure: the ‘Great Spiral’ in Lord Rosse's astronomical record books and beyond

Published online by Cambridge University Press:  17 March 2010

OMAR W. NASIM
Affiliation:
Senior Research Fellow at the Chair for Science Studies (ETH-Zurich) and Member of the NCCR Eikones Group (Univ. Basel), ETH Zentrum RAC G 14, Raemi-strasse 36, Zurich, 8092, Switzerland. Email: omar.nasim@wiss.gess.ethz.ch.

Abstract

This paper examines the interrelations between astronomical images of nebulae and their observation. In particular, using the case of the ‘Great Spiral’ (M51), we follow this nebula beginning with its discovery and first sketch made by the third Earl of Rosse in 1845, to giving an account, using archival sources, of exactly how other images of the same object were produced over the years and stabilized within the record books of the Rosse project. It will be found that a particular ‘procedure’ was employed using ‘working images’ that interacted with descriptions, other images and the telescopic object itself. This stabilized not only some set of standard images of the object, but also a very potent conception of spirality as well, i.e. as a ‘normal form’. Finally, two cases will be contrasted, one being George Bond's application of this spiral conception to the nebula in Orion, and the other Wilhelm Tempel's rejection of the spiral form in M51.

Type
Research Article
Copyright
Copyright © British Society for the History of Science 2010

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References

1 See Figure 2. ‘Spiral nebulae’ is how these objects were labelled before many of them were properly recognized as being extragalactic. On the relevant history of the development of extragalactic astronomy see Smith, Robert W., ‘Beyond the galaxy: the development of extragalactic astronomy 1885–1965, part 1’, Journal for the History of Astronomy (2008) 39, pp. 91119.CrossRefGoogle Scholar An admirable reference work has recently been published in German, especially important for the who, where and when of nineteenth-century nebular research, and for its excellent bibliography: Wolfgang Steinicke, Nebel und Sternhaufen: Geschichte ihrer Entdeckung, Beobachtung und Katalogisierung – von Herschel bis zu Dreyers ‘New General Catalogue’, Norderstedt, 2009.

2 Simon Schaffer, ‘The Leviathan of Parsonstown: literary technology and scientific representation’, in Timothy Lenoir (ed.), Inscribing Science: Scientific Texts and the Materiality of Communication, Stanford: Stanford University Press, 1998, pp. 182–222, pp. 203, 207, 221.

3 John Ruskin, Ariandne Florentina: Six Lectures on Wood and Metal Engraving, London: George Allen, 1876, pp. vii, 27–28, original emphasis. For a good account of reproduction methods see Susan Lambert, The Image Multiplied: Five Centuries of Printed Reproductions of Painting and Drawing, London: Trefoil, 1987.

4 Galison, Peter, ‘The suppressed drawing: Paul Dirac's hidden geometry’, Representations (2000) 72, pp. 145166, p. 150. Also see Daston, Lorraine, ‘On scientific observation’, Isis (2008), 99, pp. 97110CrossRefGoogle Scholar, for some relevant aspects.

5 For a detailed look at these aspects within the record books of the Rosse project see Omar W. Nasim, ‘Beobachtungen mit der Hand: Astronomische Nebelskizzen im 19. Jahrhundert’, in Christoph Hoffmann (ed.), Daten sichern: Schreiben und Zeichnen als Verfahren der Aufzeichnung, vol. 1, Zurich and Berlin, 2008. An English version was published as Omar W. Nasim, ‘Observations, descriptions, and drawings of nebulae: a sketch,’ Max Planck Institute for the History of Science Pre-print Series, no. 345, Berlin, 2008.

6 Pang, Alex Soojung-Kim, ‘Visual representation and post-constructivist history of science’, Historical Studies in the Physical and Biological Sciences (1997) 28, pp. 139171CrossRefGoogle ScholarPubMed, p. 160. For an excellent and directly relevant paper see de Rijcke, Sarah, ‘Drawing into abstraction: practices of observation and visualisation in the work of Santiago Ramon y Cajal’, Interdisciplinary Science Review (2008) 33, pp. 287311.CrossRefGoogle Scholar Also Lopes, Dominic McIvor, ‘Drawing in a social science: lithic illustration’, Perspectives on Science (2009) 17, pp. 525.CrossRefGoogle Scholar

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8 Michael Hoskin, William Herschel and the Construction of the Heavens, New York: W.W. Norton & Co., 1964, p. 129.

9 Schaffer, Simon, ‘Herschel in Bedlam: natural history and stellar astronomy’, BJHS (1980), 13, pp. 211239CrossRefGoogle Scholar. Also see William Herschel (1791), ‘On Nebulous Stars, properly so called’, in Hoskin, op. cit. (8), pp. 118–129, especially p. 119.

10 Much to Sir John Herschel's chagrin, his father's hypothesis and Laplace's speculations were conflated in what came to be known as the ‘nebular hypothesis’. A survey on the ideas related to the nebular hypothesis can be found in Stephen G. Brush, Nebulous Earth: The Origin of the Solar System and the Core of the Earth from Laplace to Jeffreys, Cambridge: Cambridge University Press, 1996. On the nebular hypothesis and the politics of development see Simon Schaffer, ‘The nebular hypothesis and the science of progress’, in James R. Moore (ed.), History, Humanity and Evolution, Cambridge: Cambridge University Press, 1989, pp. 131–164.

11 John Herschel, ‘Humboldt's Kosmos’, in idem, Essays from the Edinburgh and Quarterly Reviews, with Addresses and Other Pieces, London: Longman, Brown, Green, Longmans and Roberts, 1857, pp. 257–364, p. 287.

12 See John Herschel, Results of Astronomical Observations Made during the Years 1834, 5, 6, 7, 8, at the Cape of Good Hope: Being the Completion of a Telescopic Survey of the Whole Surface of the Visible Heavens, Commenced in 1825, London: Smith, Elder, 1847, pp. 8–11. For more, generally, on Herschel's graphical methods see Thomas Hankins, L., ‘A “large and graceful sinuosity”: John Herschel's graphical method’, Isis (2006), 97, pp. 605633CrossRefGoogle ScholarPubMed. Also see Omar W. Nasim, ‘The “landmark” and “groundwork” of stars: John Herschel, photography and the drawings of Nebulae’, forthcoming 2010.

13 Cf. Charles Piazzi Smyth, ‘On astronomical drawings’, reprinted in P. Klaus Hentschel and Axel D. Wittmann (eds.), The Role of Visual Representations in Astronomy: History and Research Practice, Thun: Verlag H. Deutsch, 2000, pp. 66–78, p. 73.

14 Airy, George Biddell, ‘History of Nebulae and clusters of stars’, presidential address, Monthly Notices of the Royal Astronomical Society (1836) 3, pp. 167174.Google Scholar, p. 173. This sentiment is also expressed in Smyth, op. cit. (13); and in a review, Rev. Russell, C.W., ‘The Monster Telescopes, erected by the Earl of Rosse …’, Dublin Review (March 1845) 18, pp. 143Google Scholar, p. 3.

15 Thomas R. Robinson to Rosse, 7 April 1876, Birr Castle Archives, Birr (hereafter BCA), K.5.49.

16 Quoted in Agnes Clerke, The Herschels and Modern Astronomy, New York: Cassell & Co., 1895, p. 153. Contrast this to what he declared publicly a year later in Herschel, John, ‘Account of some observations made with a 20-feet reflecting telescope’, Memoirs of the Astronomical Society of London (1826) 2, pp. 459497Google Scholar, p. 470.

17 John Herschel, op. cit. (12), p. 22.

18 For more on Lord Rosse see Patrick Moore, The Astronomy of Birr Castle, London: Mitchell Beazley, 1971; and Hoskin, Michael, ‘The Leviathan of Parsonstown: ambitions and achievements’, Journal for the History of Astronomy (2002) 33, pp. 5770.CrossRefGoogle Scholar

19 Rosse, , ‘Observations on the Nebulae’, Philosophical Transactions of the Royal Society of London (1850) 140, pp. 449514Google Scholar, p. 499.

20 See Hoskin, Michael, ‘Rosse, Robinson, and the resolution of the nebulae’, Journal for the History of Astronomy (1990) 22, pp. 331344CrossRefGoogle Scholar; for a detailed look at the different ways a nebular hypothesis might be used see also Schaffer, op. cit. (10).

21 This is how J.L.E. Dreyer referred to this discovery in a retrospective article he wrote, as ‘the last survivor’ of the Rosse team, in his ‘Rosse's six-foot reflector’, Observatory (1914) 37, pp. 399–402, p. 399.

22 Herschel, John, ‘Observations of nebulae and clusters of stars, made at Slough, with a twenty-feet reflector, between the Years 1825 and 1833’, Philosophical Transactions of the Royal Society of London (1833), 123, pp. 359505CrossRefGoogle Scholar, pp. 496–497.

23 The caption reads: ‘Fig 25 Herschell [sic] 51 Messier, sketched April 1845, carefully compared with original on different nights, but no micrometer employed. Handed round the Section at the Cambridge meeting.’ Also see Hoskin, Michael, ‘The first drawing of a spiral nebula’, Journal for the History of Astronomy (1982), 13, pp. 97101CrossRefGoogle Scholar.

24 Quoted in ‘The Leviathan Telescope and its revelations’, Fraser's Magazine (December 1850) 42, pp. 591–601, p. 598.

25 ‘Notes and abstracts of communication’, Report of the Fifteenth Meeting of the British Association for the Advancement of Science Held at Cambridge in June 1845, London, 1846, p. 4.

26 Kessler introduces a possible ‘initial sketch’ prior to the 1845 image shown here in Figjure 2. However, the image she suggests (her Figure 2) is actually taken from an observing book that contains observations beginning in 1848 (Birr Castle Archives, L/2/6). It is therefore not the ‘initial sketch’ towards the more detailed original image shown at the meeting, as Kessler claims it is. See Kessler, Elizabeth, ‘Resolving the nebulae: the science and art of representing M51’, Studies in History and Philosophy of Science (2007), 38, pp. 477491CrossRefGoogle Scholar, especially p. 481.

27 It seems that no records were kept of the discovery; see fourth Earl of Rosse, Observations of Nebulae and Clusters of Stars Made with the Six-Foot and Three-Foot Reflectors by Birr Castle, from the Year 1848 up to the Year 1878, Dublin: Royal Dublin Society, 1880, Series II, 2, pp. 1–178, p. 127.

28 Bailey, M.E., Butler, C.J. and McFarland, J., ‘Unwinding the discovery of spiral nebulae’, Astronomy & Geophysics (2005) 46, pp. 2.262.28CrossRefGoogle Scholar, p. 2.27, original emphasis.

29 See Earl of Rosse, , ‘Observations on some of the nebulae’, Philosophical Transactions of the Royal Society of London (1844) 134, pp. 321324CrossRefGoogle Scholar.

30 Alexander von Humboldt, Cosmos: A Sketch of a Physical Description of the Universe, vol. 6, London, 1852, pp. 334–335.

31 John Le Conte (1816–1887), an Edinburgh artist, and a stipple and line engraver, produced this mezzotint of M51.

32 Although it must be noted that Rosse would occasionally privately circulate positively printed images of nebulae, mostly mezzotint engravings, to other nebular researchers; see quotation by d'Arrest in Edward S. Holden, Monograph of the Central Parts of the Nebula of Orion, Washington Astronomical Observations for 1878 – Appendix I, Washington: Government Printing Office, 1882, p. 102 n.

33 Letter from G.J. Stoney to Rosse, 17 June 1862, BCA, K.13.1.

34 John Herschel, in a letter to Rosse from 1862, also agrees with Stoney, and says, ‘The effect of the figures … on blank ground is exceedingly successful and very far in advance to any previous pictorial attempt to exhibit these objects’. J. Herschel to Rosse, 23 June 1862, BCA, K.2.28 (1).

35 Letter from Rev. Rambaut to Rosse, 9 March 1878, BCA, L/5–1, original emphasis.

36 This information is taken from the Armagh Observatory website, which contains a list describing some of the drawings made by Rambaut using dark paper (grey or black) and chalk, while using Rosse's telescopes. see http://www.arm.ac.uk/history/archives.html#Sect16.

37 Letter from G. Stokes to Lord Oxmantown, 31 August 1867, BCA, K.15.6.

38 And earlier; see for instance W. Herschel, ‘Astronomical Observations relating to the Construction of the Heavens … ’ (1811), in Hoskin, op. cit. (8), pp. 133–150.

39 See remarks to this effect made in Rosse, op. cit. (19), 509. Also see Pang, op. cit. (6), esp. pp. 160 and 161.

40 See Airy, op. cit. (14), pp. 173–174.

41 T.W.B, , ‘Rosse on the Nebulae’, Astronomical Register (April 1863) 1, pp. 4951Google Scholar, p. 51.

42 Smyth, op. cit. (13), p. 73.

43 The reverse of nature in both the printed reproductions and the initial sketches is thus immediately connected to issues of ‘representational realism’. See Michael Lynch and S.Y. Edgerton Jr. ‘Aesthetics and digital image processing: representational craft in contemporary astronomy’, in G. Fyfe and J. Law (eds.), Picturing Power: Visual Depiction and Social Relations, London: Routledge, 1988, pp. 184–220, esp. p. 212.

44 John Pringle Nichol, Thoughts on Some Important Points Relating to the System of the World, Edinburgh, 1846, pp. 18, 21, 24, 25. Note that ‘development’ still plays a role here in Nichol's thought. For more on this see Schaffer, op. cit. (9); also see idem, op. cit. (2), p. 215.

45 In the ninth edition of the Architecture of the Heavens, Nichol continued to advance the ‘brother-system’ view and included in this edition of the work a reproduction of Rosse's Great Spiral: John Pringle Nichol, The Architecture of the Heavens, 9th edn, London, 1851.

46 For more on this see Nasim, ‘Beobachtungen’, op. cit. (5).

47 The size of a page in one of these observing books is estimated to be about 20.3 cm×13 cm. The books were bought from J. Tallon, Jun., Stationer & Account Book Manufacturer, 95 Grafton Street, Dublin. Cf. BCA, L/1/1.

48 Rosse briefly describes the procedure: ‘The original observations are in books, in which they were entered each night: from time to time they were copied into a folio [Ledger 1] in the order of right ascension; and of that folio a copy was made for ordinary use in the Observatory [Ledger 2]’, Rosse, , ‘On the construction of specula of six-feet aperture; and a selection from the observations of nebulae made with them’, Philosophical Transactions of the Royal Society of London (1861) 151, pp. 681745CrossRefGoogle Scholar, p. 705.

49 Rosse, op. cit. (19), pp. 505, 509.

50 The ledger pictured here (BCA, L/2/1), in Figure 6, I believe, is the one used in the office, and thus the one into which material from the observing books was first copied by the observers, in this case Stoney. I will refer to this, then, as Ledger 1.

51 Rosse, op. cit. (19), p. 508.

52 Letter from G.J. Stoney to Rosse, 22 November 1850, BCA, K.17.34 (2), original emphasis.

53 Compare Lynch and Edgerton, op. cit. (43), especially pp. 202–203.

54 Entry in ledger for 28 April 1848, BCA, L/1/1.

55 Entry for 17 March 1855, BCA, L/2/1.

56 See Nasim, ‘Beobachtungen’, op. cit. (5).

57 Rosse, op. cit. (48), p. 728.

58 From Hunter's Observing Book, Birr Castle Archives, L–1/4. For Rosse's remark about Hunter see Lord Oxmantown [to be the fourth Earl of Rosse], ‘An account of the observations on the Great Nebula in Orion, made at Birr Castle, with the 3-Feet and 6-Feet telescopes, between 1848 and 1867, with a drawing of the Nebula’, Philosophical Transactions of the Royal Society of London (1868) 158, pp. 57–73, esp. p. 66 n.

59 Joseph Meder, The Mastery of Drawing (tr. and revised by Winslow Ames, in two volumes), vol. 1, New York: Abaris, 1978, p. 118.

60 Observing Book, entry for 30 April 1863, BCA, L/1/4.

61 To be sure, there is another illustration that is included alongside the descriptions and records (fourth Earl of Rosse, op. cit. (32), p. 130), made by one of the later assistants, Copeland. The sketch is a composite and was not to be considered a ‘standard’ image.

62 The four standard finished images are: the first 1845 drawing (Figure 2), the 1850 (Figure 5), Hunter's image of 1864 (Figure 10) and finally Bindon Blood Stoney's unpublished finished drawing of M51 (also on its way to being very faint).

63 Consider Rosse's statement: ‘and as observations have accumulated the subject has become, to my mind at least, more mysterious and more inapproachable’; Rosse, op. cit. (19), p. 503.

64 Rosse believed, as early as 1850, ‘that such a system should exist, without internal movement, seems to be in the highest degree improbable … we cannot regard such a system in any way as a case of mere statical equilibrium’. Rosse, op. cit. (19), p. 504, and also p. 503. The internal movement was not actually seen in ‘the object in space’, in other words, but the strong impression of its dynamic was given in the sketches. On the determination of internal motion in spiral nebulae, see the important work of Hetherington, Norriss S., ‘Edwin Hubble's examination of internal motions of spiral nebulae’, Quarterly Journal of the Royal Astronomical Society (1974), 15, pp. 392418Google Scholar.

65 Rosse, op. cit. (48), p. 702, my italics.

66 Rosse, op. cit. (29), p. 505.

67 On the importance on forming habits within scientific practice, and its relation to ontology and epistemology, see Daston, op. cit. (4), p. 100.

68 Rosse, op. cit. (48), p. 703; there were exceptions, the most important being the nebula in Orion.

69 Rosse [30 November 1853], ‘Address delivered before the Royal Society,’ Abstracts of the Papers Communicated to the Royal Society of London (1850–1854) 6, pp. 343–372, pp. 347–48; my italics.

70 There is a chance that this ‘visitor’ might have been Charles Piazzi Smyth, whose signature may be found in the Guest Book of the Observatory for the year 1852.

71 A sheet pasted to the back of the ledger, BCA, L/2/1.

72 Lorraine Daston and Peter Galison, Objectivity, New York: Zone, 2007, especially p. 82. In our case, instead of being faced with some ‘transphenomenal’ type we are presented with an instance, in Rosse's figures. I stress this because it differs from earlier Romantic schemes. Cf. Bernhard Kleeberg, ‘Ideal (geometrical) types and epistemologies of morphology’, in Erna Fiorentini (ed.), Observing Nature – Representing Experience: The Osmotic Dynamics of Romanticism, 1800–1850, Berlin: Reimer, 2007, pp. 187–204.

73 Rosse, op. cit. (69), p. 348; also see Omar W. Nasim, ‘On seeing an image of a spiral nebula: from Whewell to Flammarion’, Nuncius (2010), forthcoming.

74 Dewhirst and Hoskin list fifty-seven spiral or suspected spirals in Rosse's 1861 catalogue; see Table 2 in Dewhirst, David W. and Hoskin, Michael, ‘The Rosse Spirals’, Journal for the History of Astronomy (1991) 22, pp. 257266CrossRefGoogle Scholar, p. 261.

75 For a nice comparison and collection of the drawings of M51 see William Tobin and J.Holberg, B., ‘A newly-discovered accurate early drawing of M51, the Whirlpool Nebula’, Journal of Astronomical History and Heritage (2008), 11, pp. 107115Google Scholar, especially p. 111. For some further details on ‘the idea in observation’, especially in the late eighteenth to the early nineteenth centuries, see Daston and Galison, op. cit. (72), pp. 69–82.

76 Hoskin, to be sure, even calls it an ‘experimentum crucis of resolvability’, in Hoskin, op. cit. (20), p. 341. Also see Schaffer, op. cit. (2), pp. 199–200.

77 For more on the supposed resolvability of the nebula in Orion to help justify the immense costs of the new telescope at the Harvard College Observatory see Schaffer, op. cit. (2), p. 218.

78 George Bond, P., ‘On the spiral structure of the Great Nebula of Orion’, Monthly Notices of the Royal Astronomical Society (1861), 21, pp. 203207CrossRefGoogle Scholar, pp. 204, 205.

79 Bond, op. cit. (78), pp. 204, 205, 206; my italics.

80 Bond, op. cit. (78), p. 206, my italics.

81 Lord Oxmantown, op. cit. (58), p. 63; and Lassell, William, ‘Miscellaneous observations with the four-foot equatoreal at Malta, article II’, Memoirs of the Royal Astronomical Society (1867), 37, pp. 3351Google Scholar, p. 33.

82 Holden translated a section of Secchi's publication of 1868 in Holden, op. cit. (32), pp. 91–98, quotation taken from p. 97. For Secchi's original see his ‘Sulla grande nebulosa di Theta Orione’, Mem. Ital. Soc. Firenze (1868), 1, no. 4.

83 Holden, op. cit. (32), pp. 82, 121.

84 One typically finds in the records of the nebular researchers such techniques as this used by Lassell: ‘Surveyed this star for some time, without any impression of a nebula about it. At length I began to conceive that the glare around it, which I had attributed to the splendour of the star, might be really nebulous; and on further looking attentively at the stars, I could fancy they were on a black ground in the midst of the nebulae; but, without the suggestion of Rosse's drawing, I think the appearance would have escaped me.’ Lassell, William, ‘Observations of the Nebula of Orion, made at Valletta, with the twenty-foot equatoreal’, Monthly Notices of the Royal Astronomical Society (1854), 14, pp. 7476CrossRefGoogle Scholar, p. 76, my italics.

85 Editor, ‘Notes’, Observatory (1878) 1, pp. 292–94.

86 Wilhelm Tempel, ‘Schreiben des Herrn Tempel, Astronomen der Koenigl. Sternwarte zu Arcetri an den Herausgeber’, Astronomische Nachrichten (1877) 90, no. 2139, pp. 33–42, p. 38.

87 Dreyer, Johan, ‘Spiral form of nebulae’, Observatory (1878), 2, pp. 370371Google Scholar; Tempel, Wilhelm, ‘Spiral form of nebulae’, Observatory (1878), 2, pp. 403405Google Scholar; and Dreyer, Johan, ‘Spiral form of nebulae II’, Observatory (1878), 2, pp. 2223Google Scholar.

88 Dreyer, op. cit. (87), ‘Spiral form of nebulae’, pp. 370–71.

89 Wilhelm Tempel, ‘Osservazioni e disegni di alcune nebule’, 1879, MS, Library of the Arcetri Astrophysical Observatory, Florence, Tavola XXI, p. 1; underlining in the original. My translation.

90 Tempel, op. cit. (87), p. 405.

91 Tempel, Wilhelm, ‘Note on the nebula near Merope’, Monthly Notices of the Royal Astronomical Society (1879), 40, pp. 622623CrossRefGoogle Scholar, p. 622. It ought to be noted, however, that the Rosse team had some experience in just such techniques, especially in the case of the Dumb-Bell Nebula. See Rosse, op. cit. (19), p. 507.

92 Also see, for instance, Tempel, op. cit. (86), pp. 35–36.

93 Tempel, op. cit. (87), p. 404, original emphasis.

94 Tempel, op. cit. (89), Tavola XXI.

95 Tempel, op. cit. (87), p. 404. Also see idem, Ueber Nebelflecken: Nach Beobachtungen Angestellt in den Jahren 1876–79 mit dem Reflector von Amici, Prague: Verlag der Königl. böhm. Gesellschaft der Wissenschaften, 1885. In the latter Tempel provides some of the details of his drawing techniques and his procedure; see n. 8, pp. 24–25.

96 Tempel, op. cit. (87), p. 404.

97 Cf. Daston and Galison, op. cit. (72), Chapter 3.

98 Tempel, op. cit. (89), Tavola XXI, p. 2.

99 Roberts, Isaac, ‘Photograph of the nebula M 51 Canum Venaticorum’, Monthly Notices of the Royal Astronomical Society (1889), 49, pp. 389390CrossRefGoogle Scholar; Sir Robert Ball, Great Astronomers, London: Pitman, 1907, p. 286.

100 Margaret Huggins, L., ‘Astronomical drawing’, Observatory (1882), 5, pp. 358362Google Scholar, pp. 359, 360. Moreover, those carving out a particular space for astrophotography exploited the differences in the drawings made of one and the same nebula. See, for instance, Common, Andrew Ainslie, ‘Astronomical photography’, Nineteenth Century: A Monthly Review (February 1887) 120, pp. 227237Google Scholar, p. 236.

101 See, for instance, Tempel, op. cit. (95), 11–12. Also see Alex Soojung-Pang, Kim, ‘“Stars should henceforth register themselves”: astrophotography at the early Lick Observatory’, BJHS (1997), 30, pp. 177202CrossRefGoogle Scholar. Pang provides an important corrective to my simplistic and incomplete picture, given here, which seems to take for granted two separate fields, one for photography and another for the stylus. Pang shows that each of these fields would often coincide as when skilled hands contributed to a composite, or to corrections required for the success of a photographic plate, or its printing.

102 Rosse seemed to have presciently warned against both these directions, here represented by Tempel and Bond, in Rosse, op. cit. (19), pp. 503–504.