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Sloane, Sir Hans


(b. Killyleagh, County Down, Northern Ireland, 16 April 1660; d. Chelsea, London, England, 11 January 1753)

medicine, natural history.

Sloane was the youngest of seven sons born to Alexander Sloane and Sarah Hickes, daughter of the chaplain to Archbishop Laud. The Sloane family emigrated to Ireland from Scotland during the reign of James I (VI), and the name was originally written Slowman or Slowan. Hans Sloane’s first name was a compliment to the Hamiltons, earls of Clanbrassill, a family in which it was common.

After the Restoration, Sloane’s father, receiver-general of taxes from County Down for the earl of Clanbrassill, became one of the commissioners of array. In a census of the previous year he is shown as having twenty two people on his land, so he must have been a man of standing and property. He died in 1666.

In his youth Sloane turned his interest toward natural history: “I had from my youth been very much pleas’d with the Study of Plants, and other Parts of Nature, and had seen most of those Kinds of Curiosities, which are to be found either in the Fields, or in the Gardens or Cabinets of the Curious in these Parts.” Killyleagh was a center of learning and had a school of philosophy, founded by the Hamilton family; and County Down, with Strangford Lough, presented many opportunities for the study of natural history. Sloane visited Copeland Island and saw “how the sea-mews laid their eggs on the ground, so thick that he had difficulty in passing along without treading on them” and he was much intrigued with the seaweed on the shore, which the Irish were accustomed to chew in order to cure scurvy. These experiences, involving natural history and medicine, were the basis of his career.

At the age of sixteen, Sloane was taken with Spasms of spitting blood and probably suffered from an attack of tuberculosis: but “by temperance, and abstaining from wine, and other fermented liquors, and the prudent management of himself in all other respects, he avoided the consequences of a disorder which must otherwise have proved fatal to him.” Three years later, in 1679, he was well enough to go to London to study medicine. He lodged in Water Lane, next to the laboratory of the Worshipful Society of Apothecaries, where he studied chemistry under Nicolaus Staphorst and botany at the Apothecaries’ Physick Garden at Chelsea. He attended lectures on anatomy and medicine, but most important at this period of his life were his friendships with two of the greatest English men of science of the day, John Ray and Robert Boyle.

In 1683 Sloane started on his grand tour of Europe. On his way to Paris he met Nicolas Lemery; in Paris he frequented the Charité hospital and heard botany lectures by Duverney. It was impossible for a Protestant to take a degree in France, but at that time the town of Orange in Provence was still under the House of Orange. Its university gave examinations and conferred degrees but provided no instruction in medicine. Sloane graduated Doctor of Physick there on 28 July 1683, then went to Montpellier to complete his studies, working under the physicians Charles Barbeyrac, Pierre Chirac, and Pierre Magnol.

The persecution of Protestants in France was starting in 1684, when Sloane returned to London with the intention of practicing medicine. For the contributions that he had already made to botany, he was elected Fellow of the Royal Society on 21 January 1685. Robert Boyle recommended Sloane as a skillful anatomist and good botanist to the surgeon Thomas Sydenham. The latter exclaimed “That is all moghty [sic] fine, but it won’t do:... no, young man, all this is Stuff: you must go to the bedside, it is there alone that you can learn disease.” The secret of Sydenham’s fame lay in his systematic approach to the symptoms observed in his patients, and this method fitted perfectly into Stoane’s systematic study of botany; diagnosis of disease became a part of natural history. Sloane was admitted a fellow of the Royal College of Physicians of London on 12 April 1687.

Christopher Monck, second duke of Albemarle, was at that time appointed governor of Jamaica; and Sloane accompanied him as physician, sailing on 12 September 1687. The expedition was of great value to Sloane, not only giving him firsthand experience of the flora and fauna of a relatively little-known island but also enabling him to search for new drugs; it was not long since the bark of Cinchona vera had been brought to Europe and used as a febrifuge. The description of the voyage and the observations on the inhabitants, diseases, plants, animals (some of which he brought back alive), and meteorology of the West Indies make Sloane’s book on the natural history of Jamaica indispensable even today. On his return to England In 1689, Sloane found James II fled and William III on the throne.

On II May 1695, Sloane married Elizabeth, daughter of John Langley and widow of Fulk Rose, formerly of Jamaica: they lived in a house that is now 4 Bloomsbury Place. Sloane was now launched not only in the highest and scientifically the most distinguished society—his—friends included Ray, Boyle. John Locke, Samuel Pepys, Edmond Halley, and Sir Isaac Newton—but also in his profession of medicine, which became very lucrative. One guinea an hour was the value of his time, although he treated the poor for nothing. His fees, his investments in quinine bark and in sugar, and his wife’s fortune—derived from her first husband’s estates in Jamaica—made Sloane a rich man.

Sloane had four children, of whom two daughters survived infancy. The elder, Sarah, married George Stanley of Paultons, from whom the family of Sloane Stanley is descended; the younger. Elizabeth, married Colonel Charles Cadogan of Oakley, afterwards second Lord Cadogan, and ancestor of the Earls Cadogan.

Appointed physician to Queen Anne in 1712. Sloane played a small but vital (although unrecognized) part in the history of England. On 27 July 1714, a political battle was fought in the Privy Council between Henry St. John. Viscount Bolingbroke, and Robert Harley, earl of Oxford. The latter lost and was dismissed; and nothing seemed to stand in the way of the succession of the Jacobites upon the queen’s death, which appeared imminent because she had fainted at the Privy Council meeting. Rumors circulated constantly that the queen was dead (on which government stocks rose 3 percent) or that she was still alive. Sloane urged that she be bled, which was done; and she recovered sufficiently to preside over another meeting of the Privy Council, at which she had just strength enough to hand the treasurer’s staff of office to Charles Talbot, duke of Shrewsbury. The Protestant succession of George, elector of Hanover, in accordance with the Act of Settlement, was then assured, it was her certified death, after so much uncertainty, that gave rise to the expression “as dead as Queen Anne.”

On 3 April 1716, George I conferred a baronetcy on Sloane, and on 30 September 1719 he was elected president of the Royal College of Physicians of London. In that post he inspired the petition to Parliament drawing attention to the evils of alcoholism that resulted in the Gin Acts, at a time when dissolute crowds thronged the streets of London shouting “No gin, no King,” Another event of his presidency was the publication of the fourth London Pharmacopoeia, which reflected Sloane’s efforts to rationalize medical prescriptions, get rid of the disgusting ingredients that had hitherto disgraced them, discard the fetishes of superstition, and include a catalog of medicinal herbs with clear definitions of their properties and the methods by which they could be identified. When he bought his property in Chelsea, including Physick Garden, he conveyed it to the Society Apothecaries for £5 a year, on condition that every year for forty years, fifty specimens of plants of different species, grown in the garden, be supplied to the Royal Society.

It may be claimed that Sloane introduced the scientific method into medicine. In a volume of the Philosophical Transacitions of the Royal Society edited by him, he was at pains to emphasize the difference between “Matters of Fact, Experiment, or Observation, and what is called Hypothesis,” in which latter category he included the old notion of “humours.” The humoral theory could not explain the fact, made evident by experiment, that quinine reduced fever. “A poor Indian who first taught cure of an Ague, of which the Lady of the Count of Cinchon was sick, overthrew with one simple medicine, without any Preparation, all the Hypotheses and Theories of Agues, which were supported by some Scores not to say Hundreds of Volumes.”

A great believer in the importance of diet, Sloane, who became familiar with chocolate in Jamaica, found it to be more digestible when mixed with milk. The resulting product was known as “Sir Hans Sloane’s Milk Chocolate,” a recipe used by Messrs. Cadbury until 1885. He was consulted by the British government on the preservation of the health of ships’ crews in the Royal Navy and on the precautions to be taken against the threat of the plague of Marseilles of 1720. He also played an important part in establishing the practice of inoculation for smallpox, brought to England by Lady Mary Wortley Montagu in 1718.

In 1739 Sloane was associated with Thomas Coram in the foundation of the Foundling Hospital, and in the same year his godson, Sir Richard Manningham, founded the first Lying-in Ward in the parochial hospital of St James’s, Westminster. Sloane’s secretary, Cromwell Mortimer, started a health insurance scheme, offering to treat patients “for a certain salary, by the year.” Since he followed the principle that “Sobriety, temperance and moderation, are the best and most powerful preservatives that Nature has granted to Mankind,” it is not surprising that at a time when most remedies were useless if not injurious, Sloane’s reputation as a physician was so deservedly high.

Sloane was elected one of the two secretaries of the Royal Society in 1693. In 1727 the president, Sir Isaac Newton, died: Sloane was elected to succeed him, a post he occupied until 1741.

In 1712 Sloane felt it desirable to acquire a country house and bought the manor house at Chelsea from Lord Cheyne; but he did not move into it until 1742. Throughout his life he amassed collections. The first were botanical specimens collected in France and the West Indies: and they formed the material for his catalog of plants. His herbarium fills 337 folio volumes in the British Museum (Natural History). Sloane soon bought and added other collections of plants, animals, insects, fossils, minerals, precious stones, and ethnographical specimens: he also branched out into Egyptian, Assyrian, Etruscan, Roman, Oriental, American Indian, and Peruvian antiquities. To these were added works of art by Albrecht Dürer, Hans Holbein, and Wenzel Hollar, and a rich collection of coins and medals. Sloane’s library contained over 50,000 books and 3,500 bound volumes of manuscripts.

Such treasures demanded careful provisions in a will. Sloane might have left them to his family, but there would then have been no guarantee of their preservation intact. Eventually, in a will made in 1739, to which codicils were added in 1749 and 1751, “desiring very much that these things, tending many ways to the Glory of God, the confutation of Atheism and its consequences, the use and improvement of Physic, and other Arts and Sciences, and Benefit of Mankind, may remain together, and not be separated, and that chiefly in and about the City of London ... where they may by the great confluence of people be of most use,” he offered them to the British nation, provided the sum of £20,000 was paid to his daughters.

After Sloane’s death in 1753, the trustees whom he had appointed met; the matter was brought before Parliament, which on 7 June 1753 received the royal assent for the act enabling purchase of the museum or collection of Sir Hans Sloane. To this were added the Harleian collection of manuscripts and the Cotton Library, and the British Museum was founded. It was installed in Montague House, Great Russell Street, and was opened to the public in 1759. The natural history departments, which had been the original kernel of Sloane’s collections, were moved to the British Museum (Natural History) in South Kensington, which was opened to the public in 1881.

The names of Sloane and of his sons-in-law are dotted all over his former property in Chelsea: Sloane Street, Hans Crescent, Paultons Square, Cadogan Gardens, Oakley Street; and the Physick Garden, where Sloane worked and its curator Philip Miller established the part played by insects in pollination, still continues to serve botany.

Sloane was a fellow of the Royal Society for all but twenty-one days in sixty-eight years, the longest fellowship. When he was young, Thomas Hobbes, born at the time of the Armada, was alive; when he was old, he knew Thomas Martyn, a botanist who died after the birth of Queen Victoria.


I. Original Works. Sloane’s writings include Catalogus plantarum quae in Jamaica sponte proveniunt (London, 1696); and Voyage to Madeira, Barbadoes, and Jamaica; With the Natural History of Jamaica. 2 vols. (London. 1707–1725).

II. Secondary Literature. See Gavin de Beer, Sir Hafts Sloane and the British Museum (London, 1953), which contains bibliographical references to all the chief MSS and printed sources of information on the life and work of Sloane; William Eric St. John Brooks, Sir Hans Sloane. The Great Collector and His Circle (London, 1954); and The Sloane Herbarium. An Annotated List of the Horti Sicci Composing It; With Biographical Accounts of the Principal Contributors, based on records compiled by James Britten and with an intro. by Spencer Savage, revised and edited by J. E. Dandy (London, 1954).

Gavin de Beer

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