The Airy Papers of the Royal Greenwich Observatory Archives are cited courtesy of the Syndics of Cambridge University Library and of the Director of the Royal Greenwich Observatory. The Herschel Letters and other papers from the Royal Society Archives are cited courtesy of the Royal Society.

A portion of this research was done in preparation for an M.Phil, thesis at Cambridge University in 1988; subsequent work was done in 1991. I would like to thank Adam Perkins, curator of the Royal Greenwich Observatory Archives, for his assistance with the Airy Papers, Jim Bennett and Michael Dettelbach for their helpful comments, and especially Simon Schaffer, for his advice and encouragement.

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⁵ The first stellar spectrum was photographed by Henry Draper in 1872.

⁶ Owing to lack of enthusiasm in many of the twenty-one observatories involved, the project was never finished. The factual information in this paragraph can be found in either of the two most comprehensive accounts of the history of astronomical photography: de Vaucouleurs, Gérard, Astronomical photography, London, 1961Google Scholar; and Norman, Daniel, ‘The development of astronomical photography’, Osiris 1938, 5, 560–94.CrossRefGoogle Scholar

⁷ Gelatine was first added to collodion by Dr Richard Leach Maddox; the principle of his formula is still used today. See Lemagny, Jean-Claude and Rouillé, André (eds.), A History of Photography: Social and Cultural Perspectives (tr. Lloyd, Janet), Cambridge, 1986, 270.Google Scholar

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¹⁰ See for instance Sontag, Susan, On Photography, Middlesex, 1978Google Scholar; Barthes, Roland, Camera Lucida: Reflections on Photography (tr. Howard, Richard), London, 1982Google Scholar; and Szarkowski, John, The Photographer's Eye, London, 1980Google Scholar. Also Freund, Gisele, Photography and Society, London, 1980.Google Scholar

¹¹ A recent collection of essays by John Tagg does mention some earlier examples of the social effects of photography, discussing its use in relation to the police, psychiatry and slum clearance projects: The Burden of Representation: Essays on Photographies and Histories, London, 1988.Google Scholar

¹² The best general histories of photography are: Helmut, and Gernsheim, Alison, History of Photography, London, 1969Google Scholar; Newhall, Beaumont, The History of Photography, London, 1982Google Scholar; and Lemagny, and Rouillé, , op. cit. (7).Google Scholar

¹³ There are numerous accounts of the ‘spurious’ use of photography for such purposes as the diagnosis of insanity. The subject appears in most histories and theories of photography, probably because of the obvious social commentary involved. See Tagg, , op. cit. (11)Google Scholar, Lemagny, and Rouillé, , op. cit. (7).Google Scholar

¹⁴ Some exceptions: Crowe, Michael J. gives a valuable discussion of visual and photographic controversy surrounding the canals of Mars in The Extraterrestrial Life Debate 1750–1900: The Idea of a Plurality of Worlds from Kant to Lowell, Cambridge, 1986, see pp. 480–546Google Scholar; and Rudwick, Martin presents an excellent examination of the visual language of geology in ‘The emergence of a visual language for geological science, 1760–1840’, History of Science (1976), 14, 149–95CrossRefGoogle Scholar. Hetherington, Norriss, in Science and Objectivity: Episodes in the History of Astronomy, Ames, 1988Google Scholar, and Sheehan, William, in Planets and Perception, Tucson, 1988Google Scholar, also discuss the problematic nature of astronomical observation, with some discussion of the role of the photograph.

¹⁵ Darius, Jon, Beyond Vision, Oxford, 1984, 19Google Scholar. See Shapin, Steven, ‘The politics of observation: cerebral anatomy and social interests in the Edinburgh phrenology disputes’, in On the Margins of Science: The Social Construction of Rejected Knowledge (ed. Wallis, Roy), Keele, Staffs., 1979, 139–78Google Scholar, for an excellent discussion of the way in which interests influence observation.

¹⁶ Lynch, Michael, ‘Discipline and the material form of images: an analysis of scientific visibility’, Social Studies of Science 1985, 15, 37–66.CrossRefGoogle Scholar Lynch says: ‘By “material” I mean sensible, analyzable, measurable, examinable, manipulatable and “intelligible”’ (p. 43).Google Scholar

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²¹ ‘Notice’, Monthly Notices of the Royal Astronomical Society (1850–1951), 11, 165Google Scholar. The daguerrotypes by Bond and Whipple were taken with the 15 inch equatorial refractor at Harvard, and the images of the moon obtained were 5 inches in diameter. Vaucouleurs, , op. cit. (6), 19–20.Google Scholar

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⁶² Norman Lockyer, P. J. C. Janssen and William Muggins almost simultaneously introduced a method for spectroscopically viewing the prominences without an eclipse in 1868, but it was not until the twentieth century that a method for observing the corona was developed. See Meadows, A. J., Science and Controversy: A Biography of Sir Norman Lockyer, London, 1972, 51–8.Google Scholar

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⁶⁵ The Kew Observatory originally had been a government observatory, but the government ceased maintenance of it in 1841. It was offered to the Royal Society, who refused it. The observatory was taken up instead by the British Association and transformed into a centre for magnetic and meteorological measurements. Sabine was an instrumental figure in this transfer, and served on the Kew Committee for many years. See Meadows, , op. cit. (62), 123.Google Scholar

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¹⁰⁹ The first series of papers, written between 1865 and 1868, was concerned with specific determinations of the characteristics of sunspots. While De la Rue co-authored the papers with Bernard Loewy, hired in 1864 to help with the reduction and measurement of the sunspot photographs, and Balfour Stewart, the director of the Kew Observatory, he did the writing himself.

As a result of these papers, the Kew observers became embroiled in a controversy with the French astronomer Faye over the structure of sunspots. This controversy, and the various theories about sunspots and the solar constitution that were proposed in the 1860s are beyond the scope of this paper. See Meadows, op. cit. (62).Google Scholar

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