(b. Hamilton, Scotland, 15 April 1710;
d. Kirknewton, near Edinburgh, 5 February 1790), chemistry, physiology, natural history, psychology. For the original article on Cullen see DSB, vol. 3.
Cullen was one of the leading chemists of eighteenth-century Europe. Although he taught many talented students, the nineteenth and early twentieth centuries remembered him primarily for the supporting role that he played in the isolation of fixed air (carbon dioxide) by his protégé Joseph Black. Such an approach was part of a larger historiography that framed most eighteenth-century chemists, Cullen and Black included, as opening acts for the new chemical nomenclature that was proposed in France at the end of the century. Although histories written in this tradition have shed much light on select topics such as heat and gas, they usually bracket most of the theories and practices that do not resemble those used by modern chemists. Recent work on Cullen and his times, however, has revealed that chemistry was an exciting enterprise that was practiced both in the laboratory and in a wide variety of local settings such as mineral wells, farmer’s fields, infirmaries, and factories. When viewed from this perspective, Cullen turns out to be an extremely original and influential thinker.
Early Career . Cullen was first educated at home and then at Hamilton Grammar School. He briefly attended the University of Glasgow in 1729, but in the same year moved on to a short-lived apprenticeship with John Paisley, a highly regarded Glaswegian surgeon-apothecary. By the end of the year he had traveled to London where he was appointed surgeon on a ship that eventually sailed to Jamaica. He returned to Scotland three years later and set up a practice outside Hamilton. During the mid-1730s he attended several courses in the University of Edinburgh Medical School, but he remained a surgeon until he acquired an MD from the University of Glasgow in 1740. The next year he married Anna Johnstone, and he continued to practice as a physician until he was appointed professor of medicine at Glasgow in 1750.
From that point forward he championed the cause of chemistry, and in 1755 he was appointed to Edinburgh’s chair in the subject. He quickly became one of the most popular lecturers. In 1766 he moved to the chair in the theory of medicine and in 1773 he settled into the chair of the practice of medicine and remained there for the rest of his career. Although he held different posts in the medical school, it was chemistry that underpinned his empirically minded approach to health and disease. His reputation and publications on these topics led to his being appointed to the Royal College of Physicians in Edinburgh (1756) and the Royal Society of London (1777). He was a longstanding member of Edinburgh’s Philosophical Society and remained active as a fellow when it became the Royal Society of Edinburgh (1783). By the time of his death in 1790 he was one of the foremost chemists in Britain and, arguably, Europe.
Like many of his mid-eighteenth-century contemporaries, Cullen classified all observable matter into five principles: salts (acids and alkalines), inflammables, waters, earths, and metals (he added an “aer” principle in the 1760s). The compounds formed by these principles were held together by forces of attraction called affinities. Although he sometimes mentioned particles or corpuscles, Cullen refrained from linking microscopic manifestations of matter to Newtonian forces. In this sense he was part of a large wave of mid-century British chemists who rejected iatromechanism, that is, the belief that illness could be reduced to laws of motion or mechanical physics. Such theories had been promoted earlier in the century, but had failed to be therapeutically useful. Instead he used heat, water, and “menstrua” (acids and alkalis) as solvents to break down material conglomerates to various combinations of the five principles. Drawing from gravimetric practices forged in metallurgy, he used weight and ratios to determine the material composition of minerals, drugs, and bodily substances. As early as the 1750s he had developed different types of diagrammatic schemes that allowed him to represent visually the compounds formed by the combination or separation of different chemical species. It was these practices that Joseph Black, one of Cullen’s protégés, would go on to refine when he performed experiments that confirmed the existence of fixed air (carbon dioxide).
Cullen was a keen promoter of in situ and in vitro experimentation, and his main concern was to define and categorize all of the matter comprehended under each principle into a reasonable classification of genera and species. He often called such arrangements “doctrines,” and they were collectively known as a “system.” Such an approach was inherently nominalistic and allowed him to continually reclassify genera and species based upon new experiments. Although he experimented on many topics, he remained interested in formulating his own “doctrine of salts” throughout his career. Because saline experimentation was the leading decompositional method used during the eighteenth century, he worked diligently to understand the composition of a wide variety of acids and alkalis. His research on this topic utilized the affinity tables first developed by Étienne-François Geoffroy in France during the 1710s. Drawing from a superior knowledge of books, monographs, and journals published across Europe, he fused his observations on affinity with the ideas offered by leading continental chemists such as Geoffroy, Hermann Boerhaave, and Georg Ernst Stahl. In addition to giving his own classification of salts, he also expanded Geoffroy’s tables by adding fifteen new columns. By the late 1750s he was distributing printed copies of the table in his chemistry lectures. It was enthusiastically received by his students, including Black, Donald Monro, George Fordyce, and Benjamin Rush.
The Usefulness of Chemistry . Throughout his career Cullen worked diligently to show that chemistry was relevant to the larger improvement of Scotland’s national economy. He gave lectures on georgics during the 1760s, and these inspired several leading agriculturalists, Lord Kames and John Anderson, for example, to use chemistry to study soil fertility. His research into Scottish potash production was also appreciated by industrialists involved in the linen, ceramic, and sulfuric acid industries. Yet even though these and other efforts put extra money in his pocket and strengthened his ties with government officials, his main experimental interests were guided by a practical concern for how chemical principles could be used to ameliorate disease. He held that substances contained “active principles” that had both positive and negative effects upon the human body. In particular he was influenced by a school of thought called neo-humoralism, which held that these principles could be used to regulate the hard and soft tissues of the body, thereby creating a balance of health. His overriding concern for identifying and systematizing the therapeutic effects of these principles led him to oversee original physiological experiments that guided the addition and removal of pharmaceutical cures contained not only in his own publications but also in the various editions of the widely read Edinburgh Pharmacopoeia (which he edited from 1773 to 1775). Indeed, his efforts to link in vitro experiments conducted in Edinburgh’s Medical School with observations made in the city’s Royal Infirmary made him one of Britain’s leaders in clinical medicine.
Because drugs were made from mineral, plant, and animal substances, Edinburgh’s primary site for systematic instruction in natural history was the Medical School. Cullen was an early convert to the utility of Carl Linnaeus’s binomial nomenclature and used it not only to create medical systems but also to order his botanical and mineralogical specimens. For minerals, however, Cullen replaced Linnaeus’s external characters (mainly color and shape) with those based on the principles of chemistry. His thoughts on this matter were influenced by the chemical mineralogies developed in continental Europe, especially in the work of Johann Pott and Axel Cronstedt. Throughout his career he actively followed international publications on this subject, especially works published by chemists connected to mining academies situated on or near the Baltic Sea. His expertise on mineralogy was respectfully acknowledged by Scotland’s landed aristocracy, for whom he sometimes assayed ores and soils. This mineralogical legacy was institutionalized when the Reverend Dr. John Walker, one of Cullen’s many protégés, was appointed as the Medical School’s professor of natural history in 1779—one of the first chairs of the subject to be established in Europe. Both Walker and Black followed in their mentor’s footsteps and taught their students how to use chemical characters to classify minerals and geological strata. Under Cullen’s guidance they also became mineralogical advisors to some of Scotland’s most powerful patrons, including Lord Bute, Lord Kames, and Lord Hopetoun.
Cullen’s therapeutic approach was based upon a vitalistic physiology that treated the nervous system as the cause of chemical and mechanical processes. Although he recognized that the mind could influence the body and vice versa, he held that thought and matter were categorically different substances. Cullen’s nervous system included not only the brain, spinal cord, and nerves but also different types of muscle fibers (especially those of the heart and stomach). As all of these “nervous fibers” regulated the hardness or softness of body tissue, they played a key role in maintaining health. In fact, Cullen coined the term neurosis to label most forms of sickness that could not be attributed to a fever or a localized disease. For such disorders he promoted both chemical and “hygenic” cures. To induce chemical cures he prescribed drugs with active principles that were known to stimulate or relax nervous fibers. He was particularly fond of the stimulatory (tonic) power of fixed air, and he regularly advised his patients to drink mineral water from spas that contained it. Hygenic cures regulated peace of mind via environmental factors. To relax nervous fibers he advised leisurely strolls in the country and spending time at spa resorts. He also prescribed novels to excite the nerves of those suffering from depression or a debilitating sickness—the most famous recipient of this cure being the philosopher Dugald Stewart.
Pedagogy and Publications . Cullen was extremely devoted to being a good lecturer. In many ways the world was his classroom. He was one of Britain’s first medical professors to lecture in the vernacular (as opposed to using Latin), and he not only gave lectures in university halls but also took his students on excursions around the Firth of Forth and the Pentland Hills (where they collected pharmaceutical simples). No matter where he might be, he was always ready to conduct an experiment—the louder and brighter, the better. From the start his students were impressed with the pedagogical efficacy of his chemically based medical systems and the enthusiasm that he had for the subject. They diligently took notes that were transcribed and bound as manuscripts that were then treated just like medical textbooks, many of which are now housed at the University of Edinburgh and the Wellcome Library in London. Once students had taken his introductory classes Cullen then supervised final dissertations on subjects that were relevant to his own industrial and medical interests. Thus, during the 1750s and 1760s Cullen’s chemical and physiological ideas were spread via manuscript notebooks, dissertations, and the high praise sung by his former students in Edinburgh, London, and Philadelphia.
Cullen’s ideas also spread throughout Europe and its colonies via his correspondence and publications. By the end of his career he was receiving hundreds of letters per year requesting advice on everything from mining to depression. Many of his responses were more essays than letters, and they often were circulated among aristocratic households and European academic societies. Cullen’s first publication was an article on the fall in temperature caused by evaporation, which appeared in the Essays and Observations, Physical and Literary(1756). It was soon combined with Black’s essay on magnesia alba and converted into a pamphlet that went through at least two editions. Because Cullen made much of his money from fees paid by students who attended his lectures, he was initially reluctant to put his ideas into print. However, his lectures were so popular that a pirated version of his materia medica course appeared. This episode, and the legal wrangling that went along with it, baptized him into the world of medico-scientific print and no doubt motivated him to publish his other lectures before he lost money on more pirated editions. He went on to write Synopsis nosologiae methodicae (1769), Institutes of Medicine (1772), and his four-volume magnum opus First Lines of the Practice of Physic (1777–1784). His books went through multiple revisions and printings, and they were translated into several European languages (including Latin, German, French, and Dutch). His work was also included in medical anthologies well into the nineteenth century. Cullen’s chemical ideas were also spread via chemistry books and articles written or translated by devoted students such as William Hunter, William Withering, Thomas Trotter, Charles Blagden, and John Brown.
SUPPLEMENTARY BIBLIOGRAPHY
The largest collection of Cullen’s personal notes and letters, along with bound copies of student notes taken in his lectures, are housed in the libraries of the University of Edinburgh, the Royal Medical Society of Edinburgh, the Royal College of Surgeons of Edinburgh, the University of Glasgow, and the Wellcome Trust, London.
WORKS BY CULLEN
“Of the Cold Produced by Evaporating Fluids, and Some Other Means of Producing Cold.” In Essays and Observations, Physical and Literary, Read before a Society in Edinburgh and Published by Them. Vol. 2, pp. 145–156. Edinburgh, 1756.
Synopsis nosologiae methodicae. Edinburgh, 1769.
Lectures on the materia medica. London: Printed for T. Loundes, 1772.
Institutes of Medicine. Edinburgh: Printed for Charles Elliot and T. Cadell, 1772.
First Lines of the Practice of Physici. Edinburgh: Printed for W. Creech, 1777–1784.
“A Cullen Manuscript of 1753.” Edited by Leonard Dobbin. Annals of Science 1 (1936): 138–156. Cullen’s classification of salts.
OTHER SOURCES
Bowman, Inci Altug. William Cullen (1710–90) and the Primacy of the Nervous System. PhD diss., Indiana University, Bloomington, 1975.
Bynum, William F., and Roy Porter, eds. Brunonianism in Britain and Europe. London: Wellcome Institute for the History of Medicine, 1988.
———, and Vivian Nutton, eds. Theories of Fever from Antiquity to the Enlightenment. London: Wellcome Institute for the History of Medicine, 1981.
Christie, John R. R. “Historiography of Chemistry in the Eighteenth Century: Hermann Boerhaave and William Cullen.” Ambix 41 (1994): 4–19.
Clow, Archibald, and Nan L. Clow. The Chemical Revolution: A Contribution to Social Technology. London: Batchworth Press, 1952.
Cowen, David L. Pharmacopoeias and Related Literature in Britain and America, 1618–1847. Aldershot, U.K.: Ashgate, 2001.
Craig, William Stuart. History of the Royal College of Physicians of Edinburgh. Oxford: Blackwell, 1976.
Doig, Andrew, et al., eds. William Cullen and the Eighteenth Century Medical World. Edinburgh: Edinburgh University Press, 1993.
Donovan, Arthur L. Philosophical Chemistry in the Scottish Enlightenment: The Doctrines and Discoveries of William Cullen and Joseph Black. Edinburgh: Edinburgh University Press, 1975.
———. “Pneumatic Chemistry and Newtonian Natural Philosophy in the Eighteenth Century: William Cullen and Joseph Black.” Isis 67 (1976): 217–228.
———. “William Cullen and the Research Tradition of Eighteenth-Century Scottish Chemistry.” In The Origins and Nature of the Scottish Enlightenment, edited by R. H. Campbell and Andrew S. Skinner, 98–114. Edinburgh: J. Donald, 1982.
Eddy, Matthew D. ‘The Doctrine of Salts and Rev John Walker’s Analysis of a Scottish Spa, 1749–1761.” Ambix 48 (2001): 137–160.
———. “Scottish Chemistry, Classification, and the Early Mineralogical Career of the ‘Ingenious’ Rev. Dr. John Walker (1746–1779).” British Journal for the History of Science 35 (2002): 411–438.
———. “Set in Stone: The Medical Language of Mineralogy in Scotland.” In Science and Beliefs: From Natural Philosophy to Natural Science, edited by David Knight and Matthew D. Eddy, 77–94. Aldershot, U.K., and Burlington, VT: Ashgate, 2005.
Golinski, Jan V. “Utility and Audience in Eighteenth-Century Chemistry: Case Studies of William Cullen and Joseph Priestley.” British Journal for the History of Science 21 (1988): 1–31.
Lawrence, Christopher. “Ornate Physicians and Learned Artisans: Edinburgh Medical Men 1726–1776.” In William Hunter and the Eighteenth-Century Medical World, edited by W. F. Bynum and Roy Porter, 153–176. Cambridge, U.K.: Cambridge University Press, 1985.
Monro, Donald. “An Account of a Pure Native Crystalised Natron, or Fossil Alkaline Salt....” Philosophical Transactions61 (1771): 567–573. Contains a chart listing Cullen’s saline affinities.
Morrell, Jack B. “The University of Edinburgh in the Late Eighteenth Century: Its Scientific Eminence and Academic Structure.” Isis 62 (1971): 158–171.
Risse, Guenter B. Hospital Life in Enlightenment Scotland: Care and Teaching at the Royal Infirmary of Edinburgh. Cambridge, U.K.: Cambridge University Press, 1986.
———. New Medical Challenges during the Scottish Enlightenment. Amsterdam: Rodopi, 2005.
Stott, Rosalie. “Health and Virtue; or, How to Keep Out of Harm’s Way: Lectures on Pathology and Therapeutics by William Cullen, c. 1770.” Medical History 31 (1987): 123–142.
Taylor, Georgette. “Unification Achieved: William Cullen’s Theory of Heat and Phlogiston as an Example of His Philosophical Chemistry.” British Journal for the History of Science 39 (2006): 477–501.
Thomson, John, W. Thomson, and David Craigie. An Account of the Life, Lectures, and Writings of William Cullen, M.D. 2 vols. Edinburgh, 1869. The best source on Cullen’s life.
Withers, Charles W. J. “William Cullen’s Agricultural Lectures and Writings and the Development of Agricultural Science in Eighteenth-Century Scotland.” Agricultural History Review 37 (1989): 144–156.
———, and Paul Wood, eds. Science and Medicine in the Scottish Enlightenment. East Linton, U.K.: Tuckwell Press, 2002.
Wright, John. “Materialism and the Life Soul in Eighteenth-Century Scottish Physiology.” In The Scottish Enlightenment: Essays in Reinterpretation, edited by Paul Wood, 177–197. Rochester, NY: University of Rochester Press, 2000.
Matthew D. Eddy
