Stephen Hales
Template:Short description Template:Other people Template:Use dmy dates Template:Infobox scientist
Stephen Hales (17 September 1677Template:Snd4 January 1761<ref>Template:Cite ODNB</ref>) was an English clergyman who made major contributions to a range of scientific fields including botany, pneumatic chemistry and physiology. He was the first person to measure blood pressure. He also invented several devices, including a ventilator, a pneumatic trough and a surgical forceps for the removal of bladder stones. In addition to these achievements, he was a philanthropist and wrote a popular tract on alcoholic intemperance.
Life
Stephen Hales was born in Bekesbourne, Kent, England. He was the sixth son of Thomas Hales, heir to Baronetcy of Beakesbourne and Brymore, and his wife, Mary (née Wood), and was one of twelve or possibly thirteen children.<ref name="Clark-Kennedy">Clark-Kennedy, A. E. Stephen Hales, D.D., F.R.S.: An eighteenth century biography. Cambridge University Press, 1929.</ref><ref name="Schofield">Template:Cite book</ref> Thomas Hales (died 1692) predeceased his father, Sir Robert Hales; therefore Sir Robert's grandson, Sir Thomas Hales, 2nd Baronet (Stephen Hales' brother) succeeded to the baronetcy in December 1693.<ref name="Schofield" />
Hales was educated in Kensington and then at Orpington before attending Corpus Christi College, Cambridge (or St Benedict's as it was then known) in 1696.<ref name="EB1911">Template:Cite EB1911</ref> Although he was an ordinand studying divinity, Hales would have received his degree in the Classics, mathematics, natural sciences and philosophy while in Cambridge. Hales was admitted as a Fellow of Corpus Christi in 1703, the same year as he obtained the degree of Master of Arts, and was ordained as Deacon at Bugden, Cambridgeshire. He continued his theological and other studies in Cambridge, where he became friends with William Stukeley who was studying medicine. He attended chemistry lectures by Giovanni Francisco Vigani while at Cambridge.<ref name="Dawson">Dawson, P. M. (1904). "The Biography of Stephen Hales, D.D., F.R.S." The Johns Hopkins Hospital Bulletin. 15 (159): 1–19.</ref> His interest in biology, botany and physiology is presumed to date from that time.<ref name="Schofield" />
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In 1709 he was ordained Priest at Fulham and on 10 August 1709 he was appointed Perpetual curate of the parish of Teddington, Middlesex and left Cambridge, although he retained his Fellowship until 1718. He became a Bachelor of Divinity in 1711.<ref>Template:Cite journal</ref> Hales remained in Teddington for the rest of his life, except for occasional visits to his other parishes. He was an assiduous minister – in addition to parish duties he enlarged and repaired the church and commissioned a new water supply for the village – and well regarded although there is some evidence that his experimental work on animal physiology was viewed with misgivings.<ref name="Clark-Kennedy" /> Thomas Twining included a verse in his poem The Boat on Hales:
- Green Teddington's serene retreat
- For Philosophic studies meet,
- Where the good Pastor Stephen Hales
- Weighed moisture in a pair of scales,
- To lingering death put Mares and Dogs,
- And stripped the Skins from living Frogs,
- Nature, he loved, her Works intent
- To search or sometimes to torment.
In 1718, the poet Alexander Pope, a renowned dog lover, also criticized Hales's work. In conversation with his friend, Joseph Spence, Pope reportedly said of Hales: "He commits most of these barbarities with the thought of its being of use to man. But how do we know that we have a right to kill creatures that we are so little above as dogs, for our curiosity, or even for some use to us?".<ref>Spence, J. (1966). Observations, anecdotes, and characters of books and men collected from conversation, James M. Osborn (ed.). Vol. 1. Oxford University Press. p. 118.</ref> Pope, however was also a close friend of Hales<ref name="Harré2002">Template:Cite book</ref> and considered him the model of the man who loves his God.<ref name="Pope">In the Epistle to a Lady, 1. 198: Works of Pope (Twickenham edn.) iii (2)</ref>
In 1718 Hales was elected a fellow of the Royal Society and in the same year became rector of Porlock, Somerset, a post he held alongside the curacy of Teddington.
In 1720 he married Mary Newce, but she died the following year, probably in childbirth;<ref name = "Clark-Kennedy 1977">Template:Cite journal</ref> there were no children and he never remarried. In 1723 he was installed as rector of Farringdon, Hampshire (which he held alongside Teddington by employing a curate in Farringdon). Hales spent his summers there and became a friend of Gilbert White, the naturalist, whose family lived nearby.
Hales's fame as a scientist grew from 1718 onwards, and by the mid part of the 18th century he had achieved an international reputation.<ref name="Clark-Kennedy" /> He was one of the eight Foreign Members of the Royal Academy of Sciences, Paris and was elected a member of the Academy of Sciences of Bologna. He received the Copley Medal in 1739 and also became a public figure as a result of his campaigns against the gin trade and his involvement in the Georgia Trust.<ref name="Clark-Kennedy" /><ref name="Schofield" /> He was made a Doctor of Divinity by Oxford University in 1733.
In his later years he received frequent visits from Frederick, Prince of Wales and his wife, Princess Augusta of Saxe-Gotha, both of whom were interested in gardening and botany. He gave Princess Augusta advice on the development of Kew Gardens,<ref name="Schofield" /> and in 1751 he was appointed Clerk of the Closet to the Princess Dowager, following the death of Prince Frederick, a post he held until his death.
At the age of seventy Hales was chosen by the president and fellows of the Royal College of Physicians to preach the annual Crounian Sermon in the church of St Mary-le-Bow. He selected his favorite topic – "The Wisdom and Goodness of God in the formation of Man".<ref name="Clark-Kennedy" /> Hales died in his 84th year at Teddington on 4 January 1761 after a short illness.<ref name="Clark-Kennedy" /> At his own request he was buried under the tower of the church where he had worked for so many years. A monument to Hales was raised by Princess Augusta in the south transept of Westminster Abbey<ref>Hall, A. R. (1966). The Abbey Scientists. London: Roger & Robert Nicholson. p. 21.</ref> after his death.<ref>Stephen Hales. Westminster Abbey. Retrieved on 15 June 2013.</ref>
Work
Hales is best known for his Statical Essays. The first volume, Vegetable Staticks (1727), contains an account of experiments in plant physiology and chemistry; it was translated into French by Georges-Louis Leclerc, Comte de Buffon in 1735<ref>Online: Statique des végétaux.</ref> and into Italian by Maria Angela Ardinghelli in Naples in 1750-1752.<ref name=":0">Template:Cite journal</ref> The second volume, Haemastaticks (1733), describes experiments on animal physiology including the measurement of the "force of the blood", i.e. blood pressure.<ref>Template:Cite journal</ref> Translated and annotated by Ardinghelli in 1756.<ref name=":0" />
Plant physiology and the chemistry of air
In Vegetable Staticks, Hales studied transpiration – the loss of water from the leaves of plants. He estimated the surface area of the leaves of the plant and the length and surface area of the roots. This allowed Hales to compare the calculated influx of water into the plant with the amount of water leaving the plant by transpiration through the leaves. He also measured 'the force of the sap' or root pressure.<ref name="medicalphysiologyonline.org">Template:Cite journal</ref> Hales commented that "plants very probably draw through their leaves some part of their nourishment from the air". In Vegetable Staticks Hales prefigured the cohesion theory of water movement in plants, although his ideas were not understood at the time, so he did not influence the debate on water transport in plants in the 19th century.<ref name="Floto">Floto, F. (1999). "Stephen Hales and the cohesion theory". Trends Plant Sci. 4 (6): 209.</ref> He also speculated that plants might use light as a source of energy for growth (i.e. photosynthesis), based on Isaac Newton's suggestion that "gross bodies and light" might be interconvertible.<ref name="Newton's Alchemy and His Theory of Matter">Template:Cite journal quoting Opticks</ref>
In Vegetable Staticks Hales also described experiments that showed that "... air freely enters plants, not only with the principal fund of nourishment by the roots, but also thro' the surface of their trunks and leaves". While Hales' work on the chemistry of air appears primitive by modern standards, its importance was acknowledged by Antoine Lavoisier, the discoverer of oxygen.<ref name="medicalphysiologyonline.org"/> Hales' invention of the pneumatic trough to collect gases over water is also considered a major technical advance. Modified forms of the pneumatic trough were later used by William Brownrigg, Henry Cavendish and Joseph Priestley in their research.<ref name="medicalphysiologyonline.org"/>
Animal physiology
Hales began his work on animal physiology with William Stuckeley while in Cambridge,<ref name = "Clark-Kennedy 1977" /> although much of it was published only after Vegetable Staticks appeared. Hales and Stuckeley performed a wide range of studies including making casts of the trachea and bronchial trees of dogs using molten lead and measuring the water lost due to breathing.<ref>Template:Cite journal</ref> Most famously, Hales made measurements of blood pressure in several animal species by inserting fine tubes into arteries and measuring the height to which the column of blood rose.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> Hales also described the effects of hemorrhage and hemorrhagic shock by progressive exsanguination of animals and accompanying measurement of blood pressure.<ref name="Macklem">Template:Cite journal</ref> In a horse he observed that as death approached "the Mare fell into cold and clammy sweats". In addition, Hales took wax casts of the ventricle of the heart and estimated how much blood was pumped by the heart; correctly described the roles of the mitral valve and aortic valve during systole and diastole; explained the pulsations of arteries in terms of their elasticity<ref>Template:Cite web</ref> and attributed the resistance to blood flow to friction due to the passage of blood through small blood vessels.<ref name="Macklem" />
Hales also described a diverse range of work in Haemastaticks including his attempts to find substances that could be used to dissolve bladder stones or calculi. This aim was unsuccessful but as part of this work he developed a double lumen bladder catheter and devised special forceps to enable the removal of urinary stones.<ref>Template:Cite journal</ref>
Hales's work on the growth pattern of long bones, demonstrating epiphyseal growth; his demonstration of spinal reflexes in the frog and his suggestion that electricity played a role in allowing nerves to control muscle function are also noteworthy.<ref>Template:Cite journal</ref>
Inventions and other work
Bad air was thought to be a cause of ill-health and death in the 18th century. Death and disease were common in overcrowded ships and prisons. Hales was one of several people in the early 18th century (other notable inventors being John Theophilus Desaguliers, Mårten Triewald and Samuel Sutton) who developed forms of ventilators to improve air quality.<ref name="Clark-Kennedy" /> Hales' ventilators were large bellows, usually worked by hand, although larger versions were powered by windmills.<ref name="Schofield" /> They were widely installed in ships, prisons and mines and were successful in reducing disease,<ref name="Clark-Kennedy" /> and aerating the lower decks of Royal Navy vessels to combat dry rot in the hulls.<ref>Template:Cite book</ref> Hales' ventilators were also used in preserving foods and drying grain.
Hales also experimented with ways of distilling fresh water from sea water; preserving water and meat on sea-voyages; measuring depths at sea; measuring high temperatures; and wrote on a range of subjects including earthquakes; methods of preventing the spread of fires; and comparative mortality rates in relationship to rural and urban parishes.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref>
Philanthropy
After the death of his wife, Hales became increasingly involved in philanthropic causes. In 1722 he became a corresponding member of the Society for Promoting Christian Knowledge, founded by Thomas Bray. In 1723 Bray became ill and appointed trustees, including Hales, to administer a bequest from Abel Tassin, Sieur d’Allone for 'The Conversion of Negroes Slaves in the West Indies'.<ref name="Clark-Kennedy" /><ref>Template:Cite journal</ref> Subsequently, Hales was also appointed a trustee for Bray's legacy for establishing parochial libraries in the American colonies. These charities became incorporated into a scheme led by James Oglethorpe to establish a charitable colony for the poor, 'honest industrious debtors' and persecuted (Protestant) foreigners. Hales may well have felt a personal commitment to this scheme since his brothers had been imprisoned for debt following the failure of the South Sea Company and one, William, died of Gaol Fever in Newgate Prison.<ref name="Schofield" />
In 1732 King George II granted a Charter for the foundation of the colony of Georgia and Hales was one of the twenty one members of the Board of Trustees.<ref name="Clark-Kennedy" /> The colony of Georgia was notable for its prohibition of slavery and rum.
As a result of his involvement with the Board of Trustees of Georgia, Hales learnt of the problems resulting from overcrowding of ships and this spurred him to invent a ship ventilator and undertake experiments to distil fresh water from sea water and to use salt to preserve meat on board ship.
Hales was one of the co-founders of the Society for the Encouragement of Arts, Manufactures and Commerce (later the Royal Society of Arts) conceived by William Shipley. Hales was also active in the movement to promote the Gin Act 1736. He wrote a number of anonymous tracts against the consumption of gin and distilled spirits, most notably 'A Friendly Admonition to the Drinker of Brandy and other Distilled Spirituous Liquors'. and also lobbied Parliament. Hales was not opposed to all alcoholic beverages<ref name="Schofield" /> but felt strongly that spirits, and gin in particular, were as he termed it 'The Bane of the Nation'.<ref name="Clark-Kennedy" />
Testimony
From the Nobel Prize in Medicine acceptance speech given by Werner Forssmann in 1956:
The genus of trees Halesia was named after him by John Ellis in 1759.<ref name="Stearns1970">Template:Cite book</ref> The American Society of Plant Biologists awards the Stephen Hales Prize<ref name="Hall">Template:Cite journal</ref><ref>Awards and Funding – Awards – American Society of Plant Biologists. My.aspb.org. Retrieved on 15 June 2012.</ref> annually to a scientist for work in plant biology.
Publications
See also
References
Further reading
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- Hales, Stephen (1727). Vegetable Staticks. London: W. and J. Innys – from the Missouri Botanical Garden's library
- Hales, Stephen (1738). "Philosophical experiments: containing useful, and necessary instructions for such as undertake long voyages at sea. Shewing how sea-water may be made fresh and wholsome: and how fresh water may be preserv'd sweet. How biscuit, corn, &c. may be secured from the weevel, meggots, and other insects. And flesh preserv'd in hot climates, by salting animals whole. To which is added, an account of several experiments and observations on chalybeate or steel-waters ... which were read before the Royal-society, at several of their meetings", London: W. Innys and R. Manby
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- Stephen Hales at the Galileo Project — details on Hales's life and work
- For a calendar of manuscript correspondence and writing of Stephen Hales see: D.G.C. Allan and R.E. Schofield, Stephen Hales. Scientist and philanthropist (London: Scolar Press, 1980), p. 178, and for his published writing see ibid p. 191
- For Hales's work as parish priest of Teddington see: David G.C. Allan, Science, Philanthropy and Religion in 18th century Teddington: Stephen Hales DD, FRS, (1677–1761) (Twickenham: Borough of Twickenham Local History Society, 2004). This work contains reconstructions of the enlargement of St Mary's Church, Hale's copyhold parsonage house and a map of his drainage scheme (Map by Ken Howe).
- For a general assessment see: David G.C. Allan, Hales, Stephen (1677–1761) in Oxford Dictionary of National Biography.
- For the 2009 celebration of his life and work see The William Shipley Group for RSA History Newsletter no. 22 (Nov 2009)
- For Hales's association with the Society of Arts see David G.C. Allan, 'Founder of the Society of Arts' group article in Oxford Dictionary of National Biography (online supplement, 2008)
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External links
- Template:UK National Archives ID
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- Hales, Stephen (1727). Vegetable staticks – digital facsimile from the Linda Hall Library
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Template:Copley Medallists 1731–1750 Template:Authority control
- Pages with broken file links
- 1677 births
- 1761 deaths
- Doctors of Divinity
- English physiologists
- 18th-century British botanists
- 18th-century English chemists
- 18th-century English inventors
- Hales family
- People from Bekesbourne
- Fellows of the Royal Society
- Members of the French Academy of Sciences
- Recipients of the Copley Medal
- Enlightenment scientists
- Alumni of Corpus Christi College, Cambridge
- Fellows of Corpus Christi College, Cambridge
- Burials at St Mary with St Alban, Teddington