Digby, Kenelm

(b. Gayhurst, Buckinghamshire, England, 11 July 1603; d. London, England, 11 June 1665),

natural philosophy, occult science.

The son of Sir Everard Digby, executed in 1606 for complicity in the Gunpowder Plot, and of Mary Mulsho of Gayhurst, Digby was brought up a Catholic. In 1617 he accompanied his uncle John Digby (later the first earl of Bristol) on a diplomatic mission to Spain. He was at Oxford, mainly under Thomas Allen, mathematician and astronomer, from 1618 to 1620, after which he set off on a tour of Europe, to France (where he attracted the attention of Marie de’ Medici), Italy, and Spain. On his return in 1623 Digby was knighted, presumably for his share, while in Spain, in entertaining Prince Charles and the duke of Buckingham.

In 1625 Digby secretly married the beautiful Venetia Stanley; five children were born, the marriage being made public after the birth of the second in 1627. In this year Digby set off on a privateering mission to the Mediterranean that involved a dramatic but scandalous attack on Venetian shipping off Scanderoon (Alexandretta; now Iskenderun); this won him considerable fame and financial rewards. Probably in the hope of preferment he was converted to Anglicanism in 1630 but returned to Catholicism on the death of his wife in 1633. His wife’s death led Digby to give up his gay public life for study. He had already interested himself in literature, alchemy, and religion; and now he turned to writing seriously upon these subjects. He had settled in France, where he met Hobbes and Mersenne, corresponded with Descartes (whom he visited in Holland), and was in close touch with other English Catholics in semiexile. Digby frequently visited England and, aside from a brief imprisonment in 1642, was free to come and go, in spite of his overt royalism. He became chancellor to the widow of Charles I, Queen Henrietta Maria, and undertook a diplomatic mission to the pope on her behalf; he also twice (1648, 1654–1655) tried to negotiate with Cromwell for toleration of Catholics. In the intervals he wrote on natural philosophy (the Two Treatises), religion, and literature; collected books and manuscripts; and collected medical, chemical, and household recipes, which he exchanged with others (such as his young relation by marriage, Robert Boyle).

In 1657 his increasingly poor health led Digby to take the waters at Montpellier, where he gave his famous account of the “powder of sympathy,” which cured wounds by being rubbed on the weapon that inflicted them. It was a strong solution of vitriol (copper sulfate) in rainwater, which could be improved by drying in the sun and by mixture with gum tragacanth. It worked by a combination of occult and natural powers, that is, by attraction and by the small material particles given off by all objects.

In the same year Digby corresponded with the mathematicians Fermat, Wallis, and Brouncker, serving as intermediary in a dispute concerning Anglo French priority rather than mathematical fact. After this Digby undertook a long journey through Germany and Scandinavia and thence, at the Restoration, home to England. He was one of those suggested as a member of the new philosophical society that soon became the Royal Society; his Discourse Concerning the Vegetation of Plants was read to them on 23 January 1661; he was named to the council in the charters of 1662 and 1663; and his name appears often in the records of their early meetings. In the Discourse Digby discusses germination, nutrition, and growth of plants in chemical and mechanical terms; he finds that saltpeter nourishes plants and concludes that, as “the Cosmopolite” (Alexander Seton, a late sixteenthcentury alchemist) had said, there is in air a food of life (saltpeter or niter) and an attractive power for this salt in the plant.

Digby was enormously admired in his own day for the fascination of his personality, the flamboyance of his early life, the romance of his love for Venetia, his position in society, and his undoubted intellectual powers. He was at once a lover of the occult and one who appreciated the new trends in natural philosophy. He never completely emancipated himself from traditional Aristotelianism, influenced, perhaps, by his conscious Catholicism and friendship for the English priest and writer Thomas White; yet he read and praised Descartes, Gassendi, and Galileo and could write as scornfully of the “Schoolmen” as they did.

Digby’s most important piece of work is the first of the Two Treatises, “Of Bodies.” Here he displays a clarity and logic of approach that show his appreciation of Descartes. In this work, which deals with both inanimate and animate bodies, he begins with basic definitions. The fundamental properties of bodies are quantity, density, and rarity; and from them motion arises. He discusses motion extensively but qualitatively, although with many admiring references to Galileo’s Two New Sciences (1638), which not many had read in 1644; he includes Galileo’s statement of the law of falling bodies but criticizes Galileo for taking too narrow and strictly functional a view (as Descartes also criticized him). Light is material and in motion; it is in fact fire and can exert pressure, so that when it strikes a body, small particles are carried off with it. Digby’s particles, which he sometimes calls atoms, are not fully characterized; they seem neither Epicurean nor Cartesian but certainly are mechanical. The weakness of the work is the lack of precision and definition; this is a general view of natural philosophy, and an interesting one, but Digby had not the ability to explore his subject deeply. Hence, although his book was widely read, it appealed to the virtuoso rather than to the scientist. As a virtuoso himself, Digby may well have intended this, especially in view of the second of Two Treatises, “Of Man’s Soul.”

BIBLIOGRAPHY

I. Original Works. Digby’s writings may be divided into scientific, theological, and personal.

Digby’s earliest scientific work is also his most important, Two Treatises, in One of which, the Nature of Bodies; in the Other, the Nature of Mans Soule, is looked into: in way of discovery, of the Immortality of Reasonable Soules (Paris, 1644; London, 1645, 1658, 1665, 1669). Best-known is his Discours fait en une célèbre assemblée, par le Chevalier Digby.... touchant la guérison des playes par la poudre de sympathie (Paris, 1658; repr. 1660, 1666, 1669, 1673), English ed., A late Discourse Made in a Solemne Assembly... touching the Cure of Wounds by the Powder of Sympathy (London, 1658; repr. 1658, 1660, 1664, 1669), and numerous eds. in German, Dutch, and Latin, often appended to other works. His third real scientific work, A Discourse Concerning the Vegetation of Plants, read before the nascent Royal Society on 23 January 1661, was first printed at London in 1661 (twice) and, as an appendix to the Two Treatises, in 1669; a French trans. was printed at Paris in 1667 and Latin eds. at Amsterdam in 1663, 1669, and 1678. Recipes purporting to come from his MSS were posthumously published in Choice and Experimented Receipts in Physick and Chirurgery... Collected by the Honourable and truly Learned Sir Kenelm Digby (London, 1668; repr. 1675); these were often selected for inclusion in collections of recipes in other languages. There is also A Choice Collection of Rare Chymical Secrets and Experiments in Philosophy, G. Hartman, ed. (London, 1682, 1685). Some of his letters on scientific subjects were printed in John Wallis, Commercium epistolicum (Oxford, 1658).

Digby’s earliest religious work is A Conference with a Lady about Choyce of Religion (Paris, 1638). There followed Observations upon Religio Medici (London, 1643; many times repr.); the Two Treatises (see above), the theological portion published as Demonstratio immortalis animae rationalis (Paris, 1651, 1655; Frankfurt, 1664); Letters... Concerning Religion (London, 1651); and A Discourse, Concerning Infallibility in Religion (Paris, 1652).

The highly miscellaneous personal works include Articles of Agreement Made Betweene the French King and those of Rochell... Also a Relation of a brave and resolute Sea Fight, made by Sr. Kenelam Digby (London, 1628); Sr. Kenelme Digbyes Honour Maintained (London, 1641); and Observations on the 22. Stanza in the 9th Canto of the 2d. Book of Spencers Faery Queen (London, 1643). There are also many posthumously published works, especially The Closet of the Eminently Learned Sir Kenelme Digbie Kt. Opened (London, 1669, 1671, 1677, 1910), on food and drink; Private Memoirs, Sir N. H. Nicolas, ed. (London, 1827); and Poems (London, 1877).

II. Secondary Literature Most important are E. W. Bligh, Sir Kenelm Digby and His Venetia (London, 1932), Which contains passages not printed in the Private Memoirs; and R. T. Petersson, Sir Kenelm Digby, the Ornament of England 1603–1665 (London, 1956).

Marie Boas Hall