This presidential address was delivered at the summer meeting of the British Society for the History of Science at the University of Leeds on 3 July 1974.

I am indebted to the Trustees of the Wedgwood Museum, Barlaston, for permission to reproduce photographs in their collections (Figures 2 and 4); also to the Delegacy of King's College, London, and to the Director of the Science Museum, London, for permission to reproduce a photograph of Wedgwood's pyrometer (Figure 3). I am grateful to Mr Bruce Tattersall, Curator of the Wedgwood Museum, Barlaston, and to Mr Ian H. C. Fraser, Archivist at Keele University Library, for supplying information about documents in the Wedgwood arcnives.

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⁴ Ibid., p. 280.

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⁶ Located in the Wedgwood Museum at Josiah Wedgwood & Sons Ltd., Barlaston, Stoke-on-Trent, Staffordshire ST12 9ES, England.

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¹⁵ Ibid., ff. 81–2.

¹⁶ Ibid., ff. 19–20.

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¹⁹ Wedgwood, Josiah, Catalogue of cameos, intaglios, medals … and other ornamental and useful articles (6th edn., Etruria, 1787), pp. 69–71.Google Scholar This edition was reprinted with a different pagination as Wedgwood's catalogue of cameos, intaglios … useful articles, ed. Meteyard, Eliza (London, 1873)Google Scholar; the relevant entry is on pp. 103–5.

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