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Hales, Stephenlocked

  • D. G. C. Allan

Stephen Hales (1677–1761)

studio of Thomas Hudson?, c. 1759

Hales, Stephen (1677–1761), natural philosopher, was born on 17 September 1677 at Beakesbourne in Kent, the tenth child and sixth son of Thomas Hales (1641–1692) and grandson of Sir Robert Hales, first baronet, a descendant of Sir John Hales, baron of the exchequer under Henry VIII. His mother, Mary (1648–1687), was the daughter of Richard Wood of Abbots Langley, Hertfordshire. Following the death of his mother in 1687, father in 1692, and grandfather in 1693, at the age of fifteen Hales became the responsibility of his elder brothers Sir Thomas Hales, second baronet, and Robert Hales, future clerk to the privy council. Having first been taught by a Mr St Clare in Kensington (c.1689–93) and then by the Revd Richard Johnson at Orpington (c.1693), Hales was placed as pupil to the Revd Mark Hildesley, newly inducted vicar of Murston, a parish to the north of Beakesbourne (1694). Hildesley, as his son the bishop records, soon discovered his 'too improveable genius especially in the philosophical way to be confined to a country parson's institutions', and he was sent to Cambridge (Mann, 713).

Introduction to science

Hales enrolled at Corpus Christi College, Cambridge, in the Easter term of 1696, and commenced residence in the following Michaelmas term. The college had been attended both by his grandfather and by the family chaplain, Thomas Ventris. Hales evidently found it congenial since he remained in residence for twelve years. He received his BA degree in the Lent term of 1700, was pre-elected a fellow of Corpus in April 1702, became a fellow in February 1703, and qualified as an MA in the following Easter term. The years of Hales's fellowship, as distinct from his time as an undergraduate, saw considerable scientific activity in the university and college; Hales together with his young friend William Stukeley participated in this. Hales designed a machine, which Stukeley drew, to represent the motion of the planets according to Newton's system. The two perambulated Cambridgeshire in search of Ray's plants; conducted chemical experiments, dissections, and electrical demonstrations; and studied optics, astronomy, and the use of telescopes and microscopes. By the time Hales left Cambridge to begin his career as a parish priest in 1709, his enduring interest in scientific matters was firmly established.

Ecclesiastical career

A family connection secured Hales's presentation to the perpetual curacy of Teddington in Middlesex, a ministry that he held until his death. He was much involved in local affairs, such as the rebuilding of the parish church and the provision of an adequate water supply for the village. He vacated his fellowship of Corpus in 1718 when he accepted the living of Porlock in Somerset, which he exchanged for that of Farringdon, Hampshire, in 1723. He found time to pay at least one visit to Porlock, and Farringdon became his summer home for many years. On 26 March 1720 he married Mary Newce, daughter of a wealthy Sussex clergyman. She died childless in 1721 and was buried at Teddington. Hales's niece Sarah Margaretta, daughter of Robert Hales, later kept house for him at Teddington and inherited the dwelling and garden, which he purchased in 1739. Hales provided his parishioners with bibles, prayer books, catechisms, and copies of the Whole Duty of Man. He imposed public penance at both Teddington and Farringdon for moral lapses. His sermons appear to have been popular, and two were published.

Hales was created a doctor of divinity by Oxford University in 1733, and the peak of his ecclesiastical career was reached with his appointment as chaplain to the princess dowager of Wales in 1751. He is supposed to have declined a canonry at Windsor when this additional honour was offered to him by George II. He was elected proctor by the diocese of Winchester for the convocation of 1754.

Physiology and other experiments

Hales was elected a fellow of the Royal Society in 1718. His experiments, which he had carried on since his Cambridge years, first came to public notice in the following year, when he read a paper to the society on the effect of the sun's rays on the sap of plants. His book on the same subject, the Vegetable Staticks (by 'staticks' he meant functional equilibrium, the measured balance of input and output), was published in 1727, and the results of similar investigations into the arterial systems of animals appeared in 1733 under the title Haemastaticks. By this date Hales's interests had become increasingly centred on the practical consequences of scientific research. He undertook experiments on food preservation and ventilation, and published Philosophical Experiments (1739), A Description of Ventilators (1743), and A Treatise on Ventilators (1758), besides numerous shorter works and monographs on related subjects.

Hales's ventilator, designed to draw fresh air into confined spaces, was publicized in the Gentleman's Magazine and was described in lectures given in the provinces by Thomas Yeoman, the engineer that made the machine. It was fitted, with successful results, on men-of-war and slave ships, in the House of Commons, the court of king's bench, Drury Lane Theatre, and Newgate prison, and in hospitals, workhouses, and gaols throughout the country. French prisoners of war held in England and English prisoners of war held in France benefited from the invention, which led Hales to say that he hoped none would accuse him of corresponding with the enemy. Showers of fresh air, he demonstrated, could be used in the distillation of sea water and to improve the taste of milk. He contributed to the mid-century debate on the causes of earthquake, in a paper read before the Royal Society in 1750 and reprinted several times.

Philanthropy and other interests

Hales received the Royal Society's Copley medal for his investigations of the complaint known as ‘the stone’ in 1739, and in the same year he was appointed by parliament as one of the trustees to examine the remedy proposed by Joanna Stephens. He was a lifelong opponent of the excessive consumption of alcohol, an insistent and fearless publicist of the evils of gin-drinking. Here his scientific work impinged on his public and religious concerns. For the Society for Promoting Christian Knowledge, of which he had been an active corresponding member since 1722, he wrote A Friendly Admonition to the Drinkers of Brandy and other Distilled Spirituous Liquors (1734), and sent copies for distribution throughout North America, in particular to the newly established proprietary colony of Georgia, of which he was trustee and common council member from 1732 to 1752 [see Trustees for establishing the colony of Georgia in America]. Other organizations that attracted his interest were the Bray Associates, a missionary and educational trust for which he worked during his years of service for the Georgia Trust, and the Society for the Propagation of the Gospel, which he remembered in his will. In 1753 he was elected a foreign associate of the Académie Royale des Sciences, and in the same year he introduced William Shipley, the founder of the Society for the Encouragement of Arts, Manufactures, and Commerce, to lords Folkestone and Romney, two influential peers whose support was essential for its success. Hales became a founding member (1754) and a vice-president (1755) of the society, and was concerned with its affairs to within a year of his death [see Founders of the Society of Arts, Manufactures, and Commerce].

Though not formally appointed preceptor to the young prince of Wales as had been rumoured in 1752, Hales guided the botanical studies of the princess, and of her children and Lord Bute. A shrub found in Carolina by Alexander Garden was given the name 'Halesia', and Hales gave drawings of it to Bute and to one of the royal children. In 1758 he helped the princess in planning a hot greenhouse, 120 feet long, to be built in the gardens at Kew.

From his likeness in the National Portrait Gallery (studio of Thomas Hudson, 1759), Hales appears a commanding figure with handsome features, certainly benevolent but clearly a man used to wielding authority over his parishioners and indifferent to those who mocked his scientific observations. In old age he had become a national figure. His work for the colony of Georgia brought him into contact with eminent politicians, religious zealots, sea captains, and American Indians. In his campaign for ventilation he was obliged to argue with hospital governors and naval officers. Yet this varied experience did nothing to alter what Peter Collinson called his 'native innocence and simplicity of manners', or to awaken in him ambition either for honours or preferment (Collinson, 273–8). He received £200 a year for his work as the princess's chaplain, a substantial increase to his income, which was useful to him for such purposes as the enlargement of the church at Teddington but otherwise, it seems, hardly welcomed. He had sufficient means to live simply and comfortably. For health's sake he always began dinner with plain pudding and yet enjoyed the delicacies produced by his syllabub machine, as well as wine, 'Nature's Cordial', preserved in cool cellars. To the young Charles Wesley he seemed, in spite of his position as a common councillor of Georgia, 'a truly pious, humble Christian' (The Journal of the Revd Charles Wesley, ed. T. Jackson, 1849, 1.56).

Alexander Pope, who was Hales's friend and neighbour in Middlesex, criticized him for his experiments on animals, but likened him to Mahmet, the king's devoted body servant:

From Peer or Bishop 'tis no easy thingTo draw the man who loves his God, or King:Alas! I copy (or my draught would fail)From honest Mah'met or Plain Parson Hale.

The Works of Alexander Pope, ed. J. Wharton, 1797, 3.222Gilbert White noted that 'His whole mind seemed replete with experiment which of course gave a tincture and turn to his conversation often somewhat peculiar, but always interesting'. He listed a series of anecdotes to support this view, among which were Hales's concern with the incrustation of ladies' tea-kettles, his advising the use of showers of water to test the salubrity of wells, his directing air-holes to be let in the outer walls of rooms, his imploring young people not to drink their tea scalding hot, his ad hoc advice to ferrymen on how to maintain the bottoms of their boats, and his teaching housewives to place inverted teacups in their pies to prevent the syrup from boiling over. 'The last act of benevolence' White saw was in a street in Farringdon, where Hales was busy painting white 'the tops of the foot-path posts, that his neighbours might not be injured by running against them in the dark' (Correspondence, 52–4).

Hales died at Teddington on 4 January 1761, after what was called a slight illness, having reached the age of eighty-three. He was buried according to his own request under the church tower at St Mary's, Teddington. 'Minister of this parish fifty one years' ran the lettering on his tomb, and there can be little doubt that he left behind him many affectionate memories among his parishioners. A monument in Westminster Abbey, carved by Wilton and paid for by the princess, shows the figures of Religion and Botanical Science supporting a medallion portrait of the dead philosopher, and a Latin inscription links him to Newton.

A reputation revived

It was the special achievement of Stephen Hales to have combined eminence in science with dedicated service as a parish priest in the Church of England. In three subjects, pneumatic chemistry, vegetable physiology, and animal physiology, Hales devised research techniques, designed experiments, and made discoveries that inspired scientists for nearly a century. By the early 1900s his scientific work was largely forgotten by scientists themselves, though in the emerging discipline of the history of science, notably in the writings of Henry Guerlac, its significance was soon to be re-established. Hales came to be regarded as a major figure in eighteenth-century science, and it was noted that in Britain his reputation was second only to that of Newton, and that every significant figure in pneumatic chemistry acknowledged his work, from Joseph Black, Henry Cavendish, and Joseph Priestley, to Antoine Lavoisier and Humphry Davy. The leading plant physiologists, from Duhamel du Monceau, through Buffon, and thence to von Sachs, had admitted the work of Hales into their considerations. And, for a hundred years, animal physiologists had come to terms with the studies of Hales before proceeding with their own work. It was a record of which any professional scientist of later times would be proud. For an eighteenth-century amateur such as Stephen Hales, incidentally trained in science and devoting major portions of his time to religion, public duties, and public service, it was considered a phenomenal achievement (Allan and Schofield, 139–40).


  • D. G. C. Allan and R. E. Schofield, Stephen Hales: scientist and philanthropist (1980)
  • A. E. Clark-Kennedy, Stephen Hales, D.D., F.R.S.: an eighteenth century biography (1929)
  • P. Collinson, ‘Memoir of Stephen Hales’, GM, 1st ser., 34 (1764), 273–8
  • GM, 1st ser., 69 (1799), 267–8
  • M. S. Mann, GM, 1st ser., 71 (1801), 712–13
  • ‘The correspondence of Robert Marsham … and Revd Gilbert White … 1790–1793’, ed. H. P. Marsham and Dr Bell, Transactions of the Norfolk and Norwich Naturalists' Society, 2 (1874–9), 133–93
  • H. Guerlac, ‘The continental reputation of Stephen Hales’, Archives Internationales d'Histoire des Sciences, 4 (1951), 393–404
  • I. B. Smith, ‘The impact of Stephen Hales on medicine’, Journal of the Royal Society of Medicine, 86 (1993), 349–52
  • J. Harrison, ‘“The ingenious Mr Yeoman” and some associates’, RSA Journal, 145 (June 1997), 53–68
  • C. H. Wilkie, The parish register of St Peter's Beakesbourne (1896)
  • N&Q, 2nd ser., 4 (1857), 407
  • J. W. Clay, ed., The registers of St Paul's Cathedral, Harleian Society, register section, 26 (1899)
  • parish register, Teddington, St Mary's, A1/14
  • W. Butler, Memoirs of Mark Hildesley (1799), 373


  • BL, observations on bills of mortality and parish registers
  • CCC Cam., MSS
  • LPL, letters
  • RCP Lond., letters
  • RS, papers
  • RSA, guard books
  • Sci. Mus., papers relating to ventilators
  • Society for Promoting Christian Knowledge, London, abstract letter-books
  • Trinity Cam.
  • United Society for the Propagation of the Gospel, London, Bray Associates MSS
  • Berks. RO, Hartley MSS
  • BL, letters to Thomas Birch
  • Bodl. Oxf., Bradley MSS
  • Cleveland Medical Library Association, Ohio, letters to William Lee
  • Linn. Soc., letters to John Ellis
  • Norfolk RO, letters to Henry Lee-Warner
  • U. Edin. L., Alston MSS


  • W. Verelst, group portrait, oils, 1734 (The Georgia Council), H. F. du Pont Winterthur Museum, Winterthur, Delaware
  • J. Macardell, mezzotint, 1759 (after T. Hudson), BM, NPG
  • studio of T. Hudson?, oils, 1759, NPG [see illus.]
  • J. Wilton, medallion on marble monument, 1762, Westminster Abbey, London
  • etching, 1799, repro. in GM, 1st ser., 69 (1799), 9
  • J. Hopwood, engraving (after T. Hudson), repro. in R. J. Thornton, Elementary botanical plates (1810)
  • J. Hopwood, engraving (after portrait by Coates), RS

Wealth at Death

copyhold dwelling house at Teddington ‘with outhouses, yard and garden’; £270 cash legacies: will, Clark-Kennedy, Stephen Hales, 240–42; index to Teddington Manor court rolls (entry for 1764)

Notes and Queries
G. E. Cokayne, , 6 vols. (1900–09)
Gentleman's Magazine