Catalogue Entry: ALCH00094

'Praxis' (certainly after 1689, probably c. 1696): an alchemical treatise, with notes and an earlier draft.

Author: Isaac Newton

Source: Ms. 420, The Babson College Grace K. Babson Collection of the Works of Sir Isaac Newton, Huntington Library, San Marino, California, USA

Custodial History

Bought at the Sotheby sale by Maggs Brothers for £34. Maggs informed Keynes on 30 July 1936 that it had been sold (but not to whom); subsequent history unclear. In 2006, following the closure of the Dibner Institute, the holdings of the Babson Collection were transferred on permanent loan to the Hungtington Library, San Marino, California.

Sotheby Lot



pp. 1-2 Latin notes on the derivation of the names of and symbols for the metals from Egyptian gods, planets, etc., apparently unrelated to the rest of the document.

p. 3 Main heading: 'Praxis'.

'Cap. 1. De Materijs Spermaticis.'

'Chap. 2/ De materia prima'

p. 8 'Cap. 3/ De Sulphure Ph[ilosoph]orum.'

p. 10 'Cap. 4/ De agente primo.'

pp. 12-20 'Chap. 5. Praxis'

pp. 11a-18a: Earlier partial drafts of chapters 4 and 5, in a separate booklet. The page numbers (introduced by the Babson College Archives) indicate the section of the main treatise to which they correspond.

An elaborate discussion of both the theoretical and practical aspects of alchemy. Though the text is densely packed with precise references to the whole range of Newton's vast reading on the subject, 'the conceptualization and organization of the work are certainly Newton's own', as Dobbs puts it (Janus Faces, 293), and she considers it 'Newton's climactic composition in alchemy' (ibid., 295).


SL420 is described in the Sotheby catalogue as only 26 pp. plus a cover, but the cover has since been designated pp. 1-2, and the other page numbers added, by the Babson College Archives. Dobbs's notes include a detailed account of the rather complex physical make-up of the document.

pp. 1-2 discussed, with a facsimile of p. 2, in Dobbs, Janus Faces, 161-3. The main treatise (pp. 3-20) printed with notes in ibid., 293-305. See also Keynes Mss. 21, 23 and 53, and Westfall, Never at Rest, 529 on the genesis of the work.

© 2019 The Newton Project

Professor Rob Iliffe
Director, AHRC Newton Papers Project

Scott Mandelbrote,
Fellow & Perne librarian, Peterhouse, Cambridge

Faculty of History, George Street, Oxford, OX1 2RL -

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