35 Facts About Stephen Hales

Stephen Hales was an English clergyman who made major contributions to a range of scientific fields including botany, pneumatic chemistry and physiology.

Stephen Hales was the first person to measure blood pressure.

Stephen Hales invented several devices, including a ventilator, a pneumatic trough and a surgical forceps for the removal of bladder stones.

Stephen Hales was the sixth son of Thomas Hales, heir to Baronetcy of Beakesbourne and Brymore, and his wife, Mary, and was one of twelve or possibly thirteen children.

Stephen 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.

Stephen Hales continued his theological and other studies in Cambridge, where he became friends with William Stukeley who was studying medicine.

Stephen Hales attended chemistry lectures by Giovanni Francisco Vigani while at Cambridge.

Stephen Hales remained in Teddington for the rest of his life, except for occasional visits to his other parishes.

Pope, however was a close friend of Stephen Hales and considered him the model of the man who loves his God.

In 1718 Stephen 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.

Stephen Hales spent his summers there and became a friend of Gilbert White, the naturalist, whose family lived nearby.

Stephen Hales 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.

Stephen Hales received the Copley Medal in 1739 and became a public figure as a result of his campaigns against the gin trade and his involvement in the Georgia Trust.

Stephen Hales was made a Doctor of Divinity by Oxford University in 1733.

At the age of seventy Stephen 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.

Stephen Hales estimated the surface area of the leaves of the plant and the length and surface area of the roots.

Stephen Hales measured 'the force of the sap' or root pressure.

Stephen Hales commented that "plants very probably draw through their leaves some part of their nourishment from the air".

In Vegetable Staticks Stephen 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.

Stephen Hales began his work on animal physiology with William Stuckeley while in Cambridge, although much of it was published only after Vegetable Staticks appeared.

Stephen Hales described the effects of hemorrhage and hemorrhagic shock by progressive exsanguination of animals and accompanying measurement of blood pressure.

Stephen Hales described a diverse range of work in Haemastaticks including his attempts to find substances that could be used to dissolve bladder stones or calculi.

Stephen Hales was one of several people in the early 18th century who developed forms of ventilators to improve air quality.

Stephen Hales' ventilators were large bellows, usually worked by hand, although larger versions were powered by windmills.

Stephen Hales' ventilators were used in preserving foods and drying grain.

Stephen Hales 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.

In 1723 Bray became ill and appointed trustees, including Stephen Hales, to administer a bequest from Abel Tassin, Sieur d'Allone for 'The Conversion of Negroes Slaves in the West Indies'.

Subsequently, Stephen Hales was appointed a trustee for Bray's legacy for establishing parochial libraries in the American colonies.

In 1732 King George II granted a Charter for the foundation of the colony of Georgia and Stephen Hales was one of the twenty one members of the Board of Trustees.

Stephen Hales was one of the co-founders of the Society for the Encouragement of Arts, Manufactures and Commerce conceived by William Shipley.

Stephen Hales was active in the movement to promote the Gin Act 1736.

Stephen Hales 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'.

Stephen Hales was not opposed to all alcoholic beverages but felt strongly that spirits, and gin in particular, were as he termed it 'The Bane of the Nation'.

Stephen Hales bled a sheep to death and then led a gun-barrel from the neck vessels into the still-beating heart.

Besides this, Stephen Hales was the first, in 1727, to determine arterial blood pressure, when he measured the rise in a column of blood in a glass tube bound into an artery.