Dictionary of National Biography, 1885-1900/Hales, Stephen
HALES, STEPHEN (1677–1761), physiologist and inventor, was born in September 1677 at Bekesbourne in Kent. His birthday is given variously as 7 Sept. and 17 Sept. He was baptised on 20 Sept. (Notes and Queries, 2nd ser. iv. 407). He was the fifth or sixth son of Thomas Hales, by Mary, daughter of Richard Wood of Abbots Langley, Hertfordshire. Thomas Hales, who was the eldest son of Sir Robert Hales, bart., died in his father's lifetime, and the baronetcy is now extinct. The family was a younger branch of the family of Hales of Woodchurch, to which Sir Edward Hales [q. v.] belonged. Stephen was entered as a pensioner at Corpus Christi College, Cambridge, on 19 June 1696, and was admitted a fellow 25 Feb. 1702–3 (M.A. 1703, B.D. 1711). In 1733 he was created D.D. by diploma of the university of Oxford.
During his residence as a fellow he became intimate with William Stukeley the antiquary, his junior by ten years, with whom he ‘perambulated’ Cambridgeshire in search of Ray's plants. He is said to have constructed an instrument for showing the movement of the heavenly bodies, a similar contrivance to that afterwards known as an orrery. He also worked at chemistry in ‘the elaboratory at Trinity College,’ no doubt that of Vigani, built by Bentley.
He was appointed perpetual curate, otherwise minister, of Teddington, Middlesex, in 1708–9. His earliest signature in the parish register occurs on 2 Jan. 1708–9. He vacated his fellowship by his acceptance of the living of Porlock in Somersetshire, which he afterwards exchanged for that of Farringdon in Hampshire. He made his home at Teddington; but it appears from a letter preserved in the Royal Society Library that he occasionally resided at Farringdon.
He became a fellow of the Royal Society on 20 Nov. 1718, and received the Copley medal of that society in 1739. He became one of the eight foreign members of the French Academy in 1753. He was proctor for the clergy of the diocese of Winchester, and one of the trustees for the colony of Georgia. In the latter capacity he preached in St. Bride's Church, London, on 21 March 1734. The sermon, a dull one on Gal. vi. 2, was afterwards published. The plant Halesia remains as a memento of this connection, having been named in his honour by the naturalist John Ellis, governor of the colony. He was active in the foundation of the Society for the Encouragement of Arts and Manufactures and Commerce, now known as the Society of Arts, and became one of its vice-presidents in 1755. Frederick, prince of Wales, the father of George III, is said to have been fond of surprising him in his laboratory at Teddington. When the prince died, there was, according to Horace Walpole, some talk of making Hales, ‘the old philosopher,’ tutor to the young prince. He was not, however, appointed to this post, and Masters (History of Corpus Christi, 1755) is probably wrong in stating that Hales had ‘some share in the instruction of her [the Princess of Wales's] illustrious offspring.’ In 1751 he was appointed clerk of the closet to the princess-dowager, and chaplain to the prince her son. She seems to have retained a regard for him, for this ‘mother of the best of kings,’ as she styles herself, put up the monument to Hales in Westminster Abbey. He declined a canonry of Windsor offered to him by the king. He was an active parish priest, as the registers of Teddington show. He made his female parishioners do public penance for irregular behaviour. He enlarged the churchyard (1734) ‘by prevailing with the lord of the manor.’ He helped his parishioners to put up (1748) a lantern on the church tower, so that the bells might better be heard. In 1754 the timber tower on which the lantern stood was pulled down, and a brick one put up in its place. Under this tower, which now serves as a porch, his bones rest. In 1753 he arranged for the building of a new aisle, and not only subscribed 200l., but personally superintended the building. In 1754 he helped the parish to a decent water supply, and characteristically records, in the parish register, that the outflow was such as to fill a two-quart vessel in ‘3 swings of a pendulum, beating seconds, which pendulum was 39 + 2/10 inches long from the suspending nail to the middle of the plumbet or bob.’ He had Peg Woffington for a parishioner and Pope for a neighbour. Spence records a remark of Pope: ‘I shall be very glad to see Dr. Hales, and always love to see him; he is so worthy and good a man.’ He is mentioned in the ‘Moral Essays,’ epistle ii. (to Martha Blount, l. 198). He was one of the witnesses to Pope's will (Courthope, Pope).
Horace Walpole calls Hales ‘a poor, good, primitive creature.’ His contemporaries speak of his ‘native innocence and simplicity of manners.’ Peter Collinson, the naturalist, writes of ‘his constant serenity and cheerfulness of mind;’ and it is recorded of him that ‘he could look even upon wicked men, and those who did him unkind offices, without any emotion of particular indignation; not from want of discernment or sensibility; but he used to consider them only like those experiments which, upon trial, he found could never be applied to any useful purpose, and which he therefore calmly and dispassionately laid aside.’ He continued some at least of his parish duties up to within a few months of his death. His signature, in a tremulous hand, occurs in the Teddington register on 4 Nov. 1760. He died on 4 Jan. 1761, ‘after a very slight illness,’ his thoughts being still busy with his scientific work. He married (1719?) Mary, daughter of Dr. Richard Newce of Much Hadham, Hertfordshire, and rector of Hailsham in Sussex. She died without issue in 1721, and was buried at Teddington on 10 Oct.
Hales's work falls into two main classes, (1) physiological and chemical, (2) inventions and suggestions on matters connected with health, agriculture, &c.
He was equally distinguished as a botanical and as an animal physiologist. His most important book, ‘Statical Essays,’ deals with both subjects. This book, founded chiefly on papers read before the Royal Society, was well received at the time, and was translated into French, German, Dutch, and Italian. It consists of two volumes, of which the first, dealing with plant-physiology, was published under the separate title of ‘Vegetable Staticks,’ in 1727.
The study of the anatomy of plants made, as Sachs points out, small advance during the eighteenth century, but there was a revival of plant-physiology, to which Hales's work was the most original and important contribution. Much of his work was devoted to the study of the loss of water which plants suffer by evaporation, and to the means by which the roots make good this loss. In these subjects many of his experiments remain of fundamental importance. With regard to the passage of water up the stems of trees it is worth notice that he made a suggestion which has quite recently, under different auspices, met with a good deal of approval, namely, that the ‘force is not from the roots only, but must proceed from some power in the stem and branches’ (Veg. Staticks, p. 110). It is especially characteristic of his work that he sought a quantitative knowledge of all the functions which he investigated. Thus he calculated the available amount of water in a given area of soil, and compared it with the loss of water due to the evaporation from the plants growing on that area. He also estimated the rain and dew fall from the same point of view; the variation in root force at different times of day; the force exerted by peas as they imbibe water and expand; the rate of growth of shoots and leaves by using the method still in use, of marking them at equal intervals.
With regard to the nutrition of plants in general he was far in advance of his age in two particulars: (1) He wrote well and clearly against the theory of the circulation of sap, then and long afterwards in vogue, a theory which rendered any advance in knowledge impossible; (2) finding that gas could be obtained from plants by dry distillation, he was led to believe that gas might be condensed or in some way changed into the substances found in plants. In thus recognising the fact that the air may be a source of food to plants, he was a forerunner of Ingen-Housz and De Saussure, the actual founders of the central principle of vegetable nutrition; but his views were not clearly enough elaborated or supported by experiment, and they failed to make much impression. He connected the assimilative function of leaves with the action of light, but, misled by the Newtonian theory as to the nature of light, he supposed that light, the substance, was itself a food.
The latter half of ‘Vegetable Staticks’ contains a mass of experiments on the gases which he distilled from various substances. He began the work in connection with his theory of the gaseous nutrition of plants, and seems to have been led on by its intrinsic interest. It led him to speculate on combustion and on the respiration of animals, and if his work had no direct chemical outcome, it prepared the way for the work of Priestley and others by teaching them how to manipulate gases by collecting them over water. His papers on sea-water and on the water of chalybeate springs also contain interesting chemical speculations.
Hales's contributions to animal physiology have been well summarised by Dr. Michael Foster: ‘He not only exactly measured the amount of blood pressure under varying circumstances, the capacity of the heart, the diameter of the blood-vessels and the like, and from his several data made his calculations and drew his conclusions, but also by an ingenious method he measured the rate of flow of blood in the capillaries in the abdominal muscles and lungs of a frog. He knew how to keep blood fluid with saline solutions, got a clear insight into the nature of secretion, studied the form of muscles at rest and in contraction, and speculated that what we now call a nervous impulse, but which was then spoken of as the animal spirits, might possibly be an electric change. And though he accepted the current view that the heat of the body was produced by the friction of the blood in the capillaries, he was not wholly content with this, but speaks of the mutually vibrating action of fluids and solids in a way that makes us feel that, had the chemistry of the time been as advanced as were the physics, many weary years of error and ignorance might have been saved.’ In first opening the way to a correct appreciation of blood pressure, Hales's work may rank second in importance to Harvey's in founding the modern science of physiology. In his work on animals and plants alike the value of what he did depends not merely on facts and principles established, but on his setting an example of the scientific method and his making widely appreciated a sound conception of the living organism as a self-regulating machine.
Hales's best known invention was that of artificial ventilators. The method of injecting air with bellows he applied to the ventilation of prisons, ships, granaries, &c. By means of a correspondence with Du Hamel, the well-known naturalist, he succeeded in getting his invention fitted to the French prisons in which English prisoners were confined. On this occasion ‘the venerable patriarch of Teddington was heard merrily to say “he hoped nobody would inform against him for corresponding with the enemy.”’ By a curious coincidence a method of ventilating similar to Hales's was brought out at the same time (1741) by Martin Triewald, captain of mechanics to the king of Sweden. The diminution in the annual mortality at the Savoy prison after Hales's ventilator had been put up seems to have been very great. Newgate also benefited in the same way.
In a letter to Mark Hildesley, bishop of Sodor and Man (Butler, Life of Hildesley, 1799), Hales writes, in 1758, of having for the last thirty years borne public testimony against drams ‘in eleven different books or newspapers,’ and adds that this circumstance ‘has been of greater satisfaction to me than if I were assured that the means which I have proposed to avoid noxious air should occasion the prolonging the health and lives of an hundred millions of persons.’ It would seem from this that he believed his efforts against spirit-drinking to have had a beneficial effect. His writings on this subject were certainly popular. His anonymous pamphlet, ‘A Friendly Admonition to the Drinkers of Brandy,’ &c., 1734, went through several editions, a sixth being published by the Society for the Promotion of Christian Knowledge in 1807. In another pamphlet, ‘Distilled Spirituous Liquors the Bane of the Nation,’ 1736, he shows the general evil arising from spirit-drinking, and seeks to rouse the interest of the landed classes by showing that dram-drinkers lose their appetites and lower the demand for provisions. The injury to the landed interest thus caused by the distillers of London he estimates at 600,000l. annually.
Hales made experiments or suggestions on the distillation of fresh from salt water; on the preservation of water and of meat in sea-voyages; on the possibility of bottling chalybeate waters; on a method of cleansing harbours; on a ‘sea-gage’ to measure unfathomable depths, the idea of which he took from the mercurial gauge with which he measured the pressure exerted by peas swelling in water; on a plan for preserving persons in hot climates from the evil effects of heavy dews; on the use of furze in fencing river banks; on winnowing corn; on earthquakes; on a method of preventing the spread of fires; on a thermometer for high temperatures; on natural purging waters, &c.
His portrait by Francis Cotes, R.A., was engraved by Hopwood, and published in R. J. Thornton's ‘Elementary Botanical Plates,’ 1810; more recently as a woodcut in the ‘Gardener's Chronicle,’ 1877, p. 17. He was also painted by Hudson, and a 12mo portrait was engraved in mezzotint by McArdell, probably from this portrait. His monument in Westminster Abbey has a bas-relief in profile by Wilton.Hales's principal works are: 1. ‘Vegetable Staticks; or an Account of some Statical Experiments on the Sap in Vegetables … also a Specimen of an Attempt to Analyse the Air …’ London, 8vo, 1727. 2. ‘Statical Essays,’ containing: vol. i. ‘Vegetable Staticks;’ vol. ii. ‘Hæmastaticks: or an Account of some Hydraulick and Hydrostatical Experiments made on the Blood and Blood-Vessels of Animals: with an Account of some Experiments on Stones in the Kidney and Bladder; … to which is added an Appendix containing Observations and Experiments relating to several Subjects in the first Volume,’ 8vo, London, 1733. 3. ‘A Friendly Admonition to the Drinkers of Brandy and other Distilled Spirit’ (anon.), London, 8vo, 1734. 4. ‘Distilled Spirituous Liquors the Bane of the Nation; being some considerations humbly offered to the Hon. the House of Commons, &c., &c. To which is added an Appendix containing the late presentments of the Grand Juries,’ &c., January 1735–6, London, 8vo, 1736. 5. ‘Philosophical Experiments: containing useful and necessary Instructions for such as undertake long Voyages at Sea; showing how Sea-water may be made fresh and wholesome, and how Fresh Water may be preserved sweet; how Biscuit, Corn, &c., may be secured from the Weevel, Maggots, and other Insects; and Flesh preserved in Hot Climates by salting Animals whole; to which is added an account of several Experiments and Observations on Chalybeate or Steel-waters, with some Attempts to convey them to distant places, preserving their virtue to a greater degree than has hitherto been done; likewise a proposal for Cleansing away Mud, &c., out of Rivers, Harbours, and Reservoirs,’ London, 8vo, 1739. 6. ‘An Account of some Experiments and Observations on Mrs. Stephens's Medicines for Dissolving the Stone …’ 8vo, London, 1740. 7. ‘A Description of Ventilators [and] a Treatise on Ventilators,’ 2 vols. 8vo, London, 1743 and 1758. 8. ‘An Account of some Experiments and Observations on Tar-Water …,’ London, 8vo, 1745. 9. ‘An Account of a Useful Discovery to Distill double the usual quantity of Sea-water, by Blowing Showers of Air up through the Distilling Liquor … and an Account of the Benefit of Ventilators …’ 8vo, London, 1756.
[Masters's Hist. of Corpus Christi College, 1753, and Lamb's edition, 1831; Annual Register, 1761, 1764; numerous passages in Gent. Mag. and Annual Register; Lysons's Environs, 1795; W. Butler's Life of Hildesley, 1799; Teddington Parish Register and Teddington Parish Magazine; Notes and Queries, passim. Two letters are preserved in the Library of the Royal Society; one letter is published in W. Butler's Life of Hildesley. The author of this work speaks of an unfortunate loss of Hales's papers. Lysons, in his Environs of London, speaks of many papers of Hales being in his possession, but these do not seem to have been published.]