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Hales, Stephen

1. Dates
Born: Beakesbourne, Kent, 17 Sept. 1677
Died: Teddington, Middlesex, 4 Jan. 1761
Dateinfo: Dates Certain
Lifespan: 84
2. Father
Occupation: Gentry
Thomas Hales was from an old and distinguished family. The grandfather, Sir Robert Hales, outlived his eldest son Thomas, who thus never held the status of baronet. Stephen Hales' mother died in 1687, when he was nine or ten, and his father five years later, in 1692.
It is clear that the family was wealthy.
3. Nationality
Birth: English
Career: English
Death: English
4. Education
Schooling: Cambridge, M.A., D.D.
Cambridge University, Bene't College (later renamed Corpus Christi), 1696-1703; B.A. 1700; M.A., 1703; B.D., 1711.
D.D. by diploma from Oxford, 1733.
5. Religion
Affiliation: Anglican
Hales was ordained in 1709 and soon thereafter took up pastoral duties that were his primary function all his life.
He was very active in the Society for the Promotion of Christian Knowledge from 1722. In 1724 he became a trustee of the D'Allone bequest, for the conversion and education of black slaves in the West Indies, and he was one of the Georgia Trustees, for the colonization of Georgia, which developed out of the D'Allone bequest.
Hales' father and grandfather had been strongly influenced by Puritanism, but Hales wholly conformed to the established church.
6. Scientific Disciplines
Primary: Botany, Physiology, Chemistry
Subordinate: Medicine
Hales is regarded as one of the founders, and perhaps the most important, of plant physiology. In Vegetables Staticks he measured the pressure of sap and the transpiration of moisture from the leaves.
He also took the most important step after Harvey and Malpighi in elucidating circulation. In Haemastatics (published in Statical Essays, 1731) he succeeded for the first time in measuring blood pressure.
His experiments (reported in Vegetables Staticks) with air, and the apparatus he devised for them stimulated the later discoveries of Black, Cavendish, Priestley, and Lavoisier.
He pursued medical issues all his life.
7. Means of Support
Primary: Church Life
Secondary: Academia, Patronage
Although the family was wealthy, there is no indication I saw that Hales received any inheritance. However, the family in effect installed him in Teddington.
He became a fellow of Bene't College in 1703 and continued to hold the fellowship after he left Cambridge until 1718, when he vacated it by accepting the living of Porlock, Somersetshire.
Perpetual curate of Teddington, Middlesex, 1709 until his death. I don't understand the meaning of the title, perpetual curate, though apparently it allowed him to retain his fellowship when the title of rector or vicar would not have. At any rate Teddington was a living worth about 87/4 per annum. The Bridgman family, who had the right of alternate presentation to Teddington, were cousins.
In 1723 he exchanged Porlock for Farringdon, Hampshire. He made his home in Teddington, but resided in Farringdon during the summers.
Appointed Clerk of the Close (i.e., Chaplain) to the Princess of Wales, 1751. This carried a salary of 200.
8. Patronage
Types: Court Official, Aristrocrat
Hales was a dedicated cleric, amply supported in his own opinion, who did not aspire to more and remained largely aloof from patronage.
He dedicated Vegetable Staticks to the Prince of Wales (later George II), and later Statical Essays to him as well.
William Cowper, the Lord Chancellor, presented him to the living of Porlock.
Although he did not seek the position with the Princess of Wales, he accepted it but refused to treat it as a sinecure. He had been close to the Prince (Frederick) before his death. After his own death the Princess erected a monument in Westminister Abbey to his memory.
The King offered him a canonry at Windsor, but he arranged to get the offer withdrawn.
9. Technological Involvement
Types: Instruments, Chemistry, Medical Practice, Pharmacology, Mechanical Devices, Agriculture, Hydraulics
Hales designed and constructed an instrument similar to an Orrery. He suggested a themometer for high temperatures, a mercurial gauge to measure the pressure of sap and a sea gauge to measure depths via pressure. He invented surgical forceps for removing stones from the urethra. Perhaps his best known and most important instrument was the pneumatic trough.
Suggestions on the preservation of sides of beef by injecting brine into the arterial system, and major improvement in the distilation of fresh water from salt water in sea-voyages. The latter involved careful calculations of the weight of coal versus the weight of water that would have otherwise to be carried along. The government put the method into use. (I categorize this under chemisty.) He also carried out extensive chemical analyses of various medicinal spring waters.
A method of preventing the spread of fires. (Without details I do not know how to categorize this.)
He was deeply involved in medicinal questions, especially with his ventilators (mechanical devices) to remove fetid air from prisons, hospitals, ships, (and grain elevators). The devices did dramatically reduce mortality, and Hales can be regarded as the one who effectively established the medicinal value of fresh air. Hales drew the inspiration for the ventilator directly from his own scientific work on the elasticity of air found in Vegetable Staticks. Haemastaticks contains medical recommendations on therapeutic bleeding and surgery, and Hales made further efforts to derive practical medicinal applications of his scientific work. His long campaign against strong liquors was as much medicinal as moral.
He worked over the years at developing a medicine that would dissolve stones. This led him into work on the medicinal value of various spring waters. It also led to his appointment to an official board to examine Mrs. Stephens' remedy, a famous nostrum at the time for the stone, which Hales came to support. Hales received the Copley Medal from the Royal Society for his work on medicine for the stone.
He designed a farm implement called the back-heaver.
His ventilator was used in drying and ventilating grain. He worked at improving the method of winnowing and cleaning grain. He also built a ventilated greenhouse for theDowager Princess of Wales; it markedly improved the plants growing in it. His Vegetable Staticks included instructions on growing hops and transplanting trees.
In Teddington, in 1754-5, Hale supervised the construction of a system of ditches that brought a new water supply to the village from a series of springs.
He was one of the founders of the Society for the Encouragement of Arts, Manufactures, and Commerce, and is one of the best examples of the application of science to use that I have found. Allan and Schofield are very good on this issue.
10. Scientific Societies
Memberships: Royal Society, Académie Royal des Sciences
Informal Connections: Intimate Friendship with W. Stukeley, after 1703. Friendship with A. Pope and H. Walpole. Correspondence with Mark Hildesley.
Royal Society, 1718. Council 1727 (and I think other times). Copley Medal, 1739.
He was one of the founders of the Society for the Encouragement of Arts, Manufactures, and Commerce (later renamed the Royal Society of Arts); Vice President, 1755.
Academy of Science at Paris, 1753.
  1. A.E. Clark-Kennedy, Stephen Hales, D.D., F.R.S. An Eighteenth Century Biography, (Cambridge, 1929).
  2. _____, "Stephen Hales, Physiologist and Botanist," Nature, 120 (1917), 228-31.
  3. Jocelyn Thorpe, "Stephen Hales," Notes and Records, 3 (1940), 53-63.
  4. Dictionary of National Biography (repr., London: Oxford University Press, 1949-50), 8, 916-20. D.G.C. Allan and Robert E. Schofield, Stephen Hales: Scientist and Philanthropist, (London, 1980). This is easily the best source on Hales.
  5. Michael Hoskin, "Forward," to Hales, Vegetable Staticks, (London, 1961). Andre Cournand, "Introduction," to Hales Statical Essays, (New York, 1964). Francis Darwin, "Stephen Hales, 1677-1761," in F.W. Oliver, ed. Makers of British Botany, (Cambridge, 1913), pp. 15-83.
Not Available and Not Consulted
  1. G.E. Burget, "Stephen Hales," Annals of Medical History, 7 (1925), 109-16.
  2. I.B. Cohen, "Stephen Hales," Scientific American, 234 (1976), 98- 107.
Compiled by:
Richard S. Westfall
Department of History and Philosophy of Science
Indiana University

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1995 Al Van Helden
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