Portrait of William Prout, by Henry Paget, in the University of Edinburgh Fine Art Collection.
School period
College/University
Gallery of William Prout
University of Edinburgh, Edinburgh, Scotland, United Kingdom
In 1808, on Jones’s recommendation, Prout entered Edinburgh University to study medicine and graduated with the Doctor of Medicine degree in 1811 with an unoriginal dissertation on fevers
Career
Gallery of William Prout
William Prout, an English chemist, physician, and natural theologian. He is remembered today mainly for what is called Prout's hypothesis.
Achievements
Membership
Royal Society
1819 - 1850
Royal Society, Carlton House Terrace, London, England, United Kingdom
Prout was elected a Fellow of the Royal Society in 1819.
Awards
Copley Medal
1827
“On the Ultimate Composition of Simple Alimentary Substances, with Some Preliminary Remarks on the Analysis of Organized Bodies in General” earned Prout the Copley Medal, the highest distinction of the Royal Society.
“On the Ultimate Composition of Simple Alimentary Substances, with Some Preliminary Remarks on the Analysis of Organized Bodies in General” earned Prout the Copley Medal, the highest distinction of the Royal Society.
University of Edinburgh, Edinburgh, Scotland, United Kingdom
In 1808, on Jones’s recommendation, Prout entered Edinburgh University to study medicine and graduated with the Doctor of Medicine degree in 1811 with an unoriginal dissertation on fevers
Connections
Acquaintance: Alexander John Gaspard Marcet
Alexander John Gaspard Marcet (1 August 1770 – 19 October 1822), was a Genevan-born physician.
An Inquiry Into the Nature and Treatment of Diabetes, Calculus, and Other Affections of the Urinary Organs: With Remarks On the Importance of ... and Bladder
On the Nature and Treatment of Stomach and Renal Diseases; Being an Inquiry Into the Connexion of Diabetes, Calculus, and Other Affections of the Kidney and Bladder With Indigestion
William Prout was a British chemist, physician, and natural theologian. He is remembered as a multifaceted physician, who conducted important research in the areas of physiology, meteorology, and chemistry. He studied the processes of digestion, respiration, and blood formation, the urinary system, urine, and urinary calculi, identified the presence of HCl in the gastric fluid.
Background
William Prout was born on January 15, 1785, in Horton, Gloucestershire, England. Prout was the eldest of three sons of John Prout, a tenant farmer whose fortunes had increased through the inheritance of land, and his wife Hannah Limbrick.
Education
Educated at local charity schools until the age of thirteen, Prout worked on his father’s farm until about 1802, when he attended the private classical academies of Rev. John Turner at Sherston, Wiltshire, and Rev. Thomas Jones at Bristol. In 1808, on Jones’s recommendation, he entered Edinburgh University to study medicine and graduated with the Doctor of Medicine degree in 1811 with an unoriginal dissertation on fevers.
Prout completed his medical training at St. Thomas’s and Guy’s hospitals in London, where he set up the practice after gaining the licentiate of the Royal College of Physicians on 22 December 1812. During 1814 Prout gave a successful course of public lectures on animal chemistry in his London home and met Alexander Marcet, who praised him in letters to Berzelius. There is some evidence that from 1816 until 1817 he edited Annals of Medicine and Surgery with his friend John Elliotson.
When his father died in 1820, Prout passed the Horton estate, which he inherited, to his surviving brother. Little is known of Prout’s personal life in London. He became a very successful, but not wealthy, physician who specialized in digestive and urinary complaints. His reputation in medicine and chemistry in Great Britain and on the Continent was considerable, both as an experimentalist and as a theorist. Unfortunately, deafness made him avoid scientific contacts after 1830. He subsequently made little effort to keep abreast of the rapid developments that took place in biochemistry and chemistry between 1830 and 1850; and although much of his biochemical research had foreshadowed that of Liebig and his school, Prout found himself eclipsed by their achievements during this period.
Prout was much influenced by Humphry Davy’s speculations on “undecompounded bodies” (1812) and by Dalton’s atomic theory as modified by Berzelius. He hoped to develop “mathematical” chemistry analogous, perhaps, to the scheme expressed tentatively by Thomas Thomson in his First Principles (1825). The inspiration to improve Gay-Lussac’s and Berzelius’ methods of organic analysis came largely from his attempt to find the mathematical laws that govern the formation of organic compounds from the elements carbon, hydrogen, oxygen, and nitrogen. In 1817, 1820, and 1827 Prout published accounts of elaborate and expensive analytical methods. His organic analyses were renowned for their accuracy, and he remained skeptical of Liebig’s simple and successful technique (1830).
Between 1815 and 1827 Prout published a series of important papers on urine and digestion that opened up the areas of purine and metabolic chemistry. He found a boa constrictor’s excrement to be 90 percent uric acid; he also extracted extremely pure urea from urine and attempted to synthesize it in 1818, ten years before Wohler’s accidental success. In 1821 Prout published a concise textbook on urine; but a similar work on digestion, partly printed in 1822, was withdrawn from publication.
In 1840, however, Prout published a long and successful practical textbook of urinary and digestive pathology. The brilliant demonstration in 1824 that the gastric juices of animals contain hydrochloric acid appeared incredible to many of Prout’s contemporaries. Yet in 1827 they readily adopted his classification of foodstuffs into water, saccharinous (carbohydrates), oleaginous (fats), and albuminous (proteins). Al-though Prout promised detailed analyses of the three organic aliments, only those of the saccharinous class were published by him.
In 1827 Prout coined the word “merorganized” to denote the isomerism and vitalization of organic substances by the presence of these incidental materials. For some years this concept was a serious alternative to the structural interpretation of isomerism. Much of this metabolic theory was speculative, as was the corpuscular theory upon which it was based. In unpublished lectures (1814) Prout supposed that hydrogen might be converted by electricity into other elements and the imponderable fluids: caloric, light, and magnetism. In 1815 he published an unsigned article in which he reconciled information on the combining weights of substances with their combining volumes when in real or imaginary gaseous states. After several dubious assumptions and adjustments, Prout calculated that the atomic weights of all elements were integral when the atomic weight of hydrogen was taken as unity. In a correction (1816) he added that hydrogen might be the primary matter from which all other “elements” were formed.
Prout quickly identified himself as the author of these papers; and the two hypotheses, of integral atomic weights and of the unity of matter, became known ambiguously and singularly as Prout’s hypothesis. It was a continuous source of inspiration to chemists and physicists until the work of F. W. Aston on isotopes in the 1920s. T. Thomson, J.B. Dumas, J.C. Marignac, and L. Meyer supported Prout, and Berzelius, E. Turner, J. S. Stas, Mendeleev, and T. W. Richards opposed him. But whatever the attitude of individual scientists toward the hypotheses or their modifications, they stimulated the improvement of analysis and enforced an interest in atomic weights and, therefore, in the atomic theory. They also gave impetus to the search for a system of classification of the elements, and, when the periodic law was achieved, they encouraged speculations about the evolution of the elements and structural theories of the atom. Few hypotheses have been so persistently fruitful.
Prout left it to others, notably T. Thomson, to work out the consequences of his suggestions; but in 1831 he added that there was no reason why the mate-rial unit of condensation might not be smaller than hydrogen (perhaps half or one-quarter of hydrogen). This offered a convenient explanation of such anomalous, nonintegral atomic weights as chlorine and copper, and it was used by Marignac and Dumas.
In his Bridgewater treatise, Prout revealed that his hypotheses were only part of an elaborate corpuscular philosophy in which spherical particles were imagined to revolve spontaneously, with mutually repulsive forces and velocities that were inversely proportional to their masses. In addition, there were attractive forces that were directly proportional to the masses of the rotating particles. Like Aepinus and Mossotti, Prout supposed that the force of gravitation was the difference between the attractive and repulsive forces. The model remained speculation because there was no way of determining angular velocities independently of atomic weights.
This polarity theory also involved Prout in conclusions similar to those drawn by Avogadro in 1811 - that at the same temperature and pressure, equal volumes of all gases contain equal numbers of molecules, and that all molecules of elementary gases contain at least two submolecules, or atoms. Like Avogadro, Prout deduced from this that the ratio of the weights of two equal volumes of different gases, at the same temperature and pressure, was equal to the ratio of their molecular weights. Prout was attacked for these views by the chemist William Charles Henry; but Prout’s support for Avogadro was without much influence, largely because he compromised with equivalent weights and because he was opposed to the use of chemical formulas.
Prout’s other significant contributions included unpublished thoughts on the unity of sensations (1810), on the distinction between taste and flavor (1812), on elaborate self-experiments regarding carbon dioxide output (1813, 1814), on a study of the chemical changes in an incubating egg (1822), on the neologism “convection” (1834), and on the design of the Royal Society’s standard barometer (183-1836).
An extremely religious man, Prout was invited to write one of the eight Bridgewater treatises, which had the general title On the Power, Wisdom, and Goodness of God, as Manifested in the Creation.
Views
As a vitalist, Prout maintained that organized bodies (which were composed of organic substances) contained “independent existing vital principles.” Under the influence of these teleological agents, the four aliments were transformed into blood and tissues. Prout termed the processes of digestion and blood formation “primary assimilation.” “Secondary assimilation” (Liebig's “metamorphosis of tissues”) included both the process of tissue formation from blood and the destruction and removal of unwanted parts from the animal system. The absorption and removal of water from processed aliments were the principal chemical features of chylification and sanguification, respectively. Organization of processed aliments could not occur, however, without the presence and admixture of minute amounts of water or of elements other than carbon, hydrogen, oxygen, and nitrogen.
Prout also believed smell was the sensation produced by substances when they were brought into contact, under particular circumstances, with the internal membrane of the nose. Its activation required the nose be moist, the substance be soluble in air, and thirdly, motion. Again, it was common experience that it was possible to suppress the sense of smell by simply holding the breath, without closing the nose. Sinuses, not being in the path of the air, did not participate in the production of this sense, as some had supposed.
Regarding the notion of flavor, Prout made use of the popular saying “a nutmeg has no taste.” No feeling of taste was generated when a portion of nutmeg or any other substance was introduced in the mouth, with the nostrils closed. This result suggested the sensation produced in the mouth by the nutmeg or any other substance, which ceased when the nostrils were closed, was really very different from taste, and hence should be given another name, which Prout believed should be flavor. Consequently, flavor should be defi as the sensation produced when substances under certain circumstances are introduced into the mouth with the nostrils opened. Flavor seemed to be a sense intermediate between taste and smell and hence it involved activation of all the factors required for the manifestation of these two senses. In the human species flavor sensing seemed to be located everywhere in the mouth.
Almost all substances containing a principle soluble both in water and air, especially the latter, produced less of flavor but the strongest sensation. Thus substances containing a volatile oil, e.g., spices, aromatics, etc., produced a strong fl, although they hardly had taste. Ammonia was an exception to this rule, it excited slightly more flavor than a common salt because of its high solubility in water.
Accepting the above arguments provided a simple explanation for the fact a person born without a tongue was able, nevertheless, to smell. Also, it explained why someone who had lost the sense of smell necessarily lost that of taste, etc. The sense of taste could, however, exist independently of smell, as Prout was acquainted with a person who had lost his smell, and consequently his flavor, but fully enjoyed the power of taste.
Quotations:
"I had come to the conclusion, that the principal alimentary matters might be reduced to the three great classes, namely the saccharine, the oily and the albuminous."
"If the views we have ventured to advance be correct, we may almost consider of the ancients to be realized in hydrogen, an opinion, by the by, not altogether new. If we actually consider the specific gravities of bodies in their gaseous state to represent the number of volumes condensed into one; or in other words, the number of the absolute weight of a single volume of the first matter which they contain, which is extremely probable, multiples in weight must always indicate multiples in volume, and vice versa; and the specific gravities, or absolute weights of all bodies in a gaseous state, must be multiples of the specific gravity or absolute weight of the first matter, because all bodies in the gaseous state which unite with one another unite with reference to their volume."
Membership
Prout was elected fellow of the Royal Society (1819) and of the Royal College of Physicians (1829). He was awarded the 1827 Copley medal of the Royal Society and elected Gulstonian lecturer at the Royal College of Physicians (1831). Among his many professional duties were a member of the Council of the Royal Society and of several of its committees and on those of the British Association for the Advancement of Science. He was also active in the Medico-Chirurgical Society of London.
Royal Society
,
United Kingdom
1819 - 1850
Personality
An accomplished organist who composed music for his family, Prout also possessed artistic talents.
Physical Characteristics:
Prout's later life was marred by deafness that affected him since childhood. This flaw led to his social and professional isolation. His health aggravated in the spring of 1850, apparently from lung problems. Before his death he requested no inspection of his body he made, so the cause was entered as “gangrene of the lungs.”
Interests
music, theater
Connections
On 22 September 1814, Prout married Agnes Adam (1793- 1863); a daughter was born in 1815, which only survived a few months. There were six further children: John William (1817-1881), Alexander Adam (1818-1854), Walter Robert (1820-1857), Thomas Jones (1823-1909), and two daughters, Elizabeth (1825-1918) and Agnes (1826-1878).