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Jan Baptista van Helmont summary

Jan Baptista van Helmont , (born Jan. 12, 1580, Brussels, Belg.—died Dec. 30, 1644, Vilvoorde, Spanish Netherlands), Belgian chemist, physiologist, and physician. Though he tended to mysticism, he was a careful observer and exact experimenter. The first to recognize gases other than air, he coined the word gas and discovered that the “wild spirits” (carbon dioxide) produced by burning charcoal and by fermenting grape juice were the same. For applying chemical principles to digestion and nutrition, he has been called the “father of biochemistry.” His collected works were published in 1648.

• van Helmont, Jan - Biology Encyclopedia

van Helmont, Jan

Flemish physician and chemist 1579–1644

Jan van Helmont was an early pioneer in the study of gases, and performed numerous chemical experiments, including an analysis of smoke, distinguishing it from ordinary air by the particles it contained. However, van Helmont is best known for a single experiment demonstrating that the weight a plant gains during growth is not due to absorption of an equal amount of soil, but instead is due (at least in part) to water.

Van Helmont undertook his famous experiment in plant growth, in part, to learn more about water. In this experiment, he carefully weighed a young willow shoot, and then planted it in a large container whose soil he had also carefully dried and weighed. He watered the willow as needed for five years, and then reweighed both the willow and the soil. The willow had grown from 2.2 kilograms (5 pounds) to 77 kilograms (169 pounds), while the dry weight of the soil had lost only 57 grams (2 ounces). In this way, van Helmont demonstrated that plants do not simply take up soil as they grow, and concluded that water was the sole source of this increased weight. However, van Helmont did not suspect that gases in the air might contribute to plant growth, a fact demonstrated by Nicolas de Saussure more than one hundred years later.

SEE ALSO Soil ; Water

Richard Robinson

Bibliography

Isley, D. "Helmont." In One Hundred and One Botanists. Ames, IA: Iowa State University Press, 1994.

Pagel, W. "J. B. Van Helmont." In Dictionary of Scientific Biography, Vol. 6. New York: Scribner's, 1972.

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• Published: 03 June 1944

J. B. Van Helmont (1579–1644)

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JEAN BAPTISTS VAN HELMONT, the great Flemish natural philosopher, died three hundred years ago, at the age of sixty-five, bringing to a close a life embittered by religious persecution, but rich in inward contentment derived from sincere piety and a magnificent record of discoveries and ingenious conceptions in science and medicine. He devised one of the early thermometers. He proposed a reform of tune measurement by the use of the pendulum and devoted much work to the investigation of its laws. He endeavoured to express vital phenomena in chemical terms and thereby became one of the founders of biochemistry. He demonstrated that acid is associated with digestion in the stomach and alkali in the duodenum. He was one of the initiators of modern pathology, which he sought to base on a study of the external agents in relation to local changes in the organs in disease. This led him to a refutation of the "Folly of Catarrh"—the title he gave to one of his treatises—for it was then believed that many diseases were due to a flow of mucus from the brain straight through the base of the skull to all parts of the body, notably to the lungs and joints, causing consumption, rheumatism, pneumonia, gout. He even made practical contributions to clinical medicine, for he examined the specific gravity of urine and demonstrated the presence of carbon dioxide and ferrous oxide in the waters of Spa by means of evaporation.

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" Acetosum Esurinum ." De morb. tartar., cap. 16.

" De simpl. medicam temp .", I, 39; ed. Kuelm. 11 , 453.

Partington, J. R., " Jean Baptista Van Helmont ", Annals of Science , 1 , 359 1936

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Partington, loc. cit. , p. 368.

Pagel, W., " The Religious and Philosophical Aspects of Van Helmont's Science and Medicine ", Supp. Bull. Hist. Med. , No. 2 (Baltimore, 1944).

Partington, loc. cit. , p. 373, lists fifteen kinds of gas described by Van Helmont and rightly emphasizes the qualitative differences which Van Helmont ascribed to them.

Pagel, W., " Van Helmont De Tempore and the History of the Biological Concept of Time ". Isis , 33 , 621 (1942).

Metzger, H., "L'Historien des Sciences doit-il se faire le contemporain des savants dont il parle?" Archeion , 15 , 34 (1933).

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PAGEL, W. J. B. Van Helmont (1579–1644). Nature 153 , 675–676 (1944). https://doi.org/10.1038/153675a0

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Jan Baptist van Helmont – The Founder of Pneumatic Chemistry

Jan Baptist van Helmont (1580-1644)

On January 12 , 1580 , Flemish chemist , physiologist , and physician Jan Baptist van Helmont was born. Can Helmont worked during the years just after Paracelsus and is sometimes considered to be “the founder of pneumatic chemistry “. Van Helmont is remembered today largely for his ideas on spontaneous generation and his introduction of the word “ gas ” (from the Greek word chaos) into the vocabulary of scientists .

“I praise my bountiful God, who hath called me into the Art of the fire, out of the dregs of other professions. For truly Chymistry… prepares the understanding to pierce the secrets of nature, and causeth a further searching out in nature, than all other Sciences being put together: and it pierceth even unto the utmost of real truth.” – Jan Baptist van Helmont [13]

Jan Baptist van Helmont – Early Years

Jan Baptist van Helmont was born in Brussels , Spanish Netherlands (present-day Belgium), as a member of the nobler families. His father, Christiaen van Helmont, was a public prosecutor . His inheritance (his father died in 1580) and the income from his wife’s fiefs made him financially independent throughout his life.  Helmont  studied philosophy, theology, natural history and medicine in a Jesuit seminary in Leuven and received his doctorate in 1599. At the age of 17 he was already a teacher. In the early 17th century , Helmont traveled through Europe , especially England , France , Italy , and Switzerland . In 1605 he returned first to Amsterdam and practiced medicine during a plague epidemic. In 1606 he settled as a doctor and natural scientist on his estate Vilvoorde near Brussels. There he carried out chemical and physiological experiments in his private laboratory. Instead of accepting the Jesuits’ offer to enter into ecclesiastical service, he married Margarite van Ranst in 1609 and thus received the title Lord. He also rejected a call from Emperor Rudolf II . Van Helmont dealt with the works of Galenus, Hippocrates , Avicenna and Paracelsus .[ 9 , 10 ] He was a follower of Paracelsus and regarded him as his model, whereas he rejected galenic medicine and, on the basis of his own research, arrived at results that contradicted the traditional concept of humoral pathology.

The Pot Experiment

The sources on Jan Baptist van Helmont differ. Often,  the scientist is credited with the idea of the pot experiment to test if plants obtained their  mass from the soil . The subject of Helmont’s experiment was the transplantation of a willow shoot weighing five pounds. Since the time of ancient Greek natural philosophy , it was assumed that all matter consisted of four elements : earth, water, fire and air. With the willow shoot, van Helmont wanted to prove that only air and water were elementary matter. He took the shoot from nature, removed the earth from its roots and weighed it. He then planted it in a pot full of weighed earth. The tree was then regularly watered with water, otherwise nothing was added. Five years after planting the willow, he pulled it out of the soil of the pot and weighed both a second time. From the earth only 2 ounces had been lost in this time, the tree however was 169 pounds and 3 ounces heavy. From this Van Helmont drew the reasonable conclusion: “ 164 pounds of wood, bark and roots originated from water alone “. Only later did research by other scholars show that plants also need air (especially the carbon dioxide it contains), light and – in much smaller quantities – substances from the soil to grow. However, many historians assume that Helmont’s experiment was mostly inspired by the work of  Nicolas of Cusa and his book ‘ De Staticus Experimentis ‘ in which a similar thought experiment is described [ 5 ].

Pneumatic Chemistry and Iatrochemistry

Jan Baptist van Helmont became the founder of iatrochemistry with Christian-mythic traits, which he opposed to iatromechanics . He described all life processes as chemical processes, which he called “fermentation” and attributed to “gaseous ferments”. In 1644 he was the first to synthesise sulphuric copper oxide ammonia (Cuprum sulphuricum ammoniatum, Kupriammonium sulphate). Van Helmont was responsible for the discovery of coal gases in the early days of modern chemistry. He discovered a “wild spirit” which emanated from heated wood and coal, and in his book “ Origins of Medicine ” (1609) called it “gas” (derived from chaos, spirit, gauze, blowing, …).

House Arrest and Ban on Publication

Jan Baptist van Helmont closely followed the controversy between the Marburg professor Rudolf Goclenius the Younger and the Belgian Jesuit Jean Roberti. In 1617 the latter had rejected the healing method of magnetic wound healing with the “sympathetic powder” published by Goclenius in 1608. A manuscript by van Helmont with extensive support of the point of view of the Protestant professor was published against his will by Roberti. His ideas brought him into conflict with the Roman Catholic Church. In 1625 the Spanish Inquisition (responsible for the Spanish Netherlands) condemned 27 statements as heresy, presumptuous arrogance, proximity to Lutheran and Calvinist doctrine. The University of Leuven rejected his teachings because they were inspired by Paracelsus. From 1633 to 1636 he was under house arrest. The persecutions by the church did not end until 1642, when he received the imprimatur for a treatise on fever. Therefore he could not publish between 1624 and 1642, until shortly before his death. Full rehabilitation did not take place until 1646 after his death.

Hero and Fool

During his lifetime, Jan Baptiste van Helmont was known as both, “ hero and fool” because his “ combination of mysticism , magic , alchemy , and new science irritated even his contemporaries”. Robert Boyle was one of Helmont’s admirers, but even Boyle could not really understand how van  Helmont one the one hand made numerous important discoveries and on the other hand “could also produce such unscientific nonsense ” [ 6 ]. Historians note that Helmont’s works are difficult to understand because often, his scientific writing is mixed with nonscientific discourses on such things as religious metaphysics and cosmology . For instance, Helmont apparently believed in spontaneous generation , that the philosophers’ stone could be used to turn other  metals into gold and that applying salve to the weapon that caused a wound would promote healing of the wound . Unfortunately, Helmont later got arrested and convicted of heresy under the Spanish Inquisition for his publication on the matter.

References and Further Reading:

• [1]  Jan Baptist von Helmont at Famous Scientists
• [2]  Misconceptions about Helmont’s Willow Experiment in A Case Study of Academic Misconduct, Peer Review Failures and Journal Coverups of Published Errors by David R. Hershey
• [3]  Johann Baptista van Helmont at Chemistry Explained
• [4] Jan Baptist van Helmont at Wikidata
• [5]  Nikolaus of Cusa and the Learned Ignorance , SciHi Blog, August 11, 2013.
• [6]  Robert Boyle – The Sceptical Chemist , SciHi Blog, December 31, 2015.
• [7] Catholic Encyclopedia:   Jan Baptista van Helmont
• [8]  Ortus Medicinae   ( Origin of Medicine , 1648)
• [9]  Paracelsus – a Typical Renaissance Scientist? , SciHi Blog
• [10]  Avicenna – The Most Significant Polymath of the Islamic Golden Age , SciHi Blog
• [11] David Hershey, Misconceptions about Helmont’s Willow Experiment . Plant Science Bulletin, The Botanical Society of America:The Society for ALL Plant Biologists, Fall 2003 vol 49, 3, pp. 78-84.
• [12] Timeline of Flemish Scientists , via DBpedia and Wikidata
• [13] Jan Baptist van Helmont at LibQuotes
• [14]  Lecture 5 Energy and Matter , BIOLogics by Dr. C @youtube

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Van Helmont, Jan Baptiste

Born : Before 12 January 1579, Brussels

Died : 30 December 1644, Brussels

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The Flemish physician Jan Baptiste van Helmont is one of the most important followers of Paracelsus. Van Helmont had a major influence on the iatrochemical movement in early modern Europe. His most important book Ortus medicinae was published posthumously and sets out his medical, philosophical, and religious worldviews. He is famous for inventing the concept and word gas .

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Bolívar, Simón: Carta de Jamaica

Mainardi, giovanni, primary literature.

Van Helmont Archives, Archiepiscopal Archives Mechelen.

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Helmont, Jan Baptiste van. 1658. Letter from van Helmont to Pierre Gassendi. 1658. In P. Gassendi, Opera omnia , 6 vols. Lyon: Laurentius Annison and Joannes Baptista Devenet. vol VI, 19–24.

Helmont, Jan Baptiste van. 1853–54. Eisagoge in artem medicam, a Paracelso restitutam. In Corneille Broeckx, Le Premier Ouvrage de J. B. van Helmont. Reprint of the 1607 ed. Annales de l’Académie Archéologique Belgique 10:327–392; and 11:119–191.

Helmont, Jan Baptiste van. 1621. Disputatio de magnetica vulnerum naturali et legitima curatione, contra R.P. Joannem Roberti . Paris: Victor Leroy.

Helmont, Jan Baptiste van. 1624. Supplementum de Spadanis fontibus . Liège: Strael.

Helmont, Jan Baptiste van. 1642. Febrium doctrina inaudita . Antwerp: Joan. Cnobbari.

Helmont, Jan Baptiste van. 1644. Opuscula medica inaudita. I. De lithiasi; II. De febribus; III. De humoribus Galeni; IV. De peste . Cologne: Jodocus Kalcoven.

Helmont, Jan Baptiste van. 1648. Ortus medicinae . Amsterdam: Elsevier.

Helmont, Jan Baptiste van. 1659. Dageraed, oft nieuwe opkomst der Geneeskonst . Amsterdam: Jan Jacob Schipper.

Helmont, Jan Baptiste van. 1662. Oriatrike or, Physick Refined . Trans. J. Chandler. London: Lodowick Loyd.

Mersenne, Marin. 1932–1946. Letters between van Helmont and Marin Mersenne. In Correspondence du P. Marin Mersenne , ed. P. Tannery and C. de Waard. Vols. I–III. Paris: PUF.

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Clericuzio, Antonio. 1993. From van Helmont to Boyle: A study of the transmission of Helmontian chemical and medical theories in seventeenth-century England. The British Journal of the History of Science 26: 303–334.

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Fransen, Sietske. 2013. Daniel Foote als Übersetzer im Kontext von Vater und Sohn van Helmont. Morgen-Glantz 23: 169–184.

Giglioni, Guido. 2000. Immaginazione e malattia: Saggio su Jan Baptiste van Helmont . Milano: FrancoAngeli.

Halleux, Robert. 1983. Helmontiana. Academiae Analecta , Klasse der Wetenschappen 45-III, 33–63.

Halleux, Robert. 1988. Theory and experiment in the early writings of Johan Baptist van Helmont. In Theory and experiment , ed. Diderik Batens and Jean Paul van Bendegem, 93–101. Dordrecht: Reidel. https://doi.org/10.1007/978-94-009-2875-6_6 .

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Harline, Craig. 2003. Miracles at the Jesus oak: Histories of the supernatural in reformation Europe . New York: Doubleday.

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Newman, William Royall, and Lawrence M. Principe. 2002. Alchemy tried in the fire: Starkey, Boyle, and the fate of Helmontian Chymistry . Chicago: University of Chicago Press.

Pagel, Walter. 1982. Joan Baptista van Helmont: Reformer of science and medicine . Cambridge/New York: Cambridge University Press.

Van de Velde, A.J.J. 1943. Geboorte en overlijden van J. B. van Helmont. Jaarboek – Koninklijke Vlaamse Academie voor Wetenschappen, Letteren en schone kunsten , 131–136.

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Jan Baptista van Helmont

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(1579–1644) Flemish chemist and physician

Van Helmont, who came from a noble Brussels family, was educated at the Catholic University of Louvain in medicine, mysticism, and chemistry, but declined a degree from them. Rejecting all offers of employment he devoted himself to private research at his home. In 1621 he was involved in a controversy with the Church over the belief that it was possible to heal a wound caused by a weapon by treating the weapon rather than the wound. Van Helmont did not reject this common belief but insisted that it was a natural phenomenon containing no supernatural elements. He was arrested, eventually allowed to remain under house arrest, and forbidden to publish without the prior consent of the Church. He wrote extensively and after his death his collected papers were published by his son as the Ortus medicinae (1648; Origin of Medicine).

Van Helmont rejected the works of the ancients, although he did believe in the philosopher's stone. He carried out careful observations and measurements, which led him to discover the elementary nature of water. He regarded water as the chief constituent of matter. He pointed out that fish were nourished by water and that substantial bodies could be reduced to water by dissolving them in acid. To demonstrate his theory he performed a famous experiment in which he grew a willow tree over a period of five years in a measured quantity of earth. The tree increased its weight by 164 pounds despite the fact that only water was added to it. The soil had decreased by only a few ounces.

Van Helmont also introduced the term ‘gas’ into the language, deriving it from the Greek for chaos. When a substance is burned it is reduced to its formative agent and its gas and van Helmont believed that when 62 pounds of wood is burned to an ash weighing 1 pound, 61 pounds have escaped as water or gas. Different substances give off different gases when consumed and van Helmont identified four gases, which he named gas carbonum, two kinds of gas sylvester, and gas pingue. These we would now call carbon dioxide, carbon monoxide, nitrous oxide, and methane.

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Video clip – Van Helmont’s experiments on plant growth

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This video clip from BBC Four Botany: A Blooming History demonstrates Van Helmont’s classic experiment to investigate how plants grow.

In 1634 Jean Baptist Van Helmont was arrested for the crime of studying plants and other phenomena. He considered the question “how do plants grow?”. The contempory theory was that plants grew by eating soil. He devised an investigation to test the idea. He weighed a willow tree and weighed dry soil. He planted the tree, watered it and then left it for 5 years. He then re-weighed the tree, which had increased in mass by over 12 stones. He dried the soil and weighed it, showing that the soil was almost the same mass. He concluded that the tree grew by drinking water. The importance of the use of scientific evidence to support ideas is discussed, even though the conclusion he made was wrong.

An good introduction to the puzzle of how plants grow. If asked, many younger pupils will believe that plants grow by taking material from the soil. The idea can be tested using rapid cycling brassicas or other fast growing species. It is also an opportunity to discuss the importance of measuring dry mass when doing experiments with living material. This can be used to develop the idea of controlling variables in experiments. The clip also raises issues about the use of scientific evidence to support conclusions. It can be used to emphasise that firm conclusions can only be drawn when clear evidence is found. Students can also discuss the gaps in Van Helmont’s knowledge, which they can fill now with current evidence.

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Fantastically Wrong: Why People Once Thought Mice Grew Out of Wheat and Sweaty Shirts

In the 17th century, physician and chemist Jean Baptiste van Helmont, apparently sick of there not being enough mice in this world, devised a home recipe for their manufacture. It was quite simple, really, far simpler than getting a girl mouse and boy mouse together with a tiny bottle of wine: “If a soiled shirt is placed in the opening of a vessel containing grains of wheat,” he wrote, “the reaction of the leaven in the shirt with fumes from the wheat will, after approximately 21 days, transform the wheat into mice.”

This, of course, may be due to mice both enjoying wheat and being capable of climbing into jars. But Helmont had another recipe for scorpions. Just get yourself a brick, carve an indentation in it, and fill it with basil. Cover that brick with another, and place in the sun. In only a few days, “fumes from the basil, acting as a leavening agent, will have transformed the vegetable matter into veritable scorpions.” Such does basil in a brick oven rise like bread … with a stinger and claws.

Helmont’s recipes were the product of some 2,000 years of fallacious thinking known as spontaneous generation. Our forebears, you see, couldn’t for the life of them figure out how maggots could just up and appear in a corpse, or how oysters just seemed to materialize in the sea. They had to have been spontaneously generating, no sex required.

The East had its own similar theories, according to Andre Brack in his book The Molecular Origins of Life . The Babylonians thought worms spontaneously erupted from canal mud, and the ancient Chinese reckoned that aphids emerged from bamboo. For the Indians, flies came from dirt and sweat.

In the West, the theory goes back to Aristotle, who put forth the first thorough writings on spontaneous generation. Some critters are lucky enough to have sex, he argued (though not in those words—I’m editorializing here), but others emerge from “putrefying earth or vegetable matter, as is the case with a number of insects.”

No, oysters are not an aphrodisiac . And they

At work here, Aristotle says, is the “vital heat” present in air . Because this air is in water and water is in earth, therefore vital heat is in everything, “so that in a sense all things are full of soul.” So in the sea, oysters spontaneously generate from the lively mud, “the earthy matter hardening round them and solidifying in the same manner as bones and horns (for these cannot be melted by fire), and the matter (or body) which contains the life being included within it.”

Aristotle’s spontaneous generation was widely accepted in Europe and the Arab world for the next two millennia. In Antony and Cleopatra , for instance, the accomplished drunkard Lepidus notes that “your Serpent of Egypt, is bred now of your mud by the operation of your Sun: so is your Crocodile.” (Though as Frederick Turner writes in Shakespeare's Twenty-First Century Economics , such drunken ramblings may have been the great writer expressing sarcastic doubt toward spontaneous generation. Regardless, the theory was alive and well.) Later on, the greatest minds of the Renaissance and Enlightenment, including Isaac Newton and René Descartes, subscribed to the theory.

Then comes along the Italian physician and naturalist Francesco Redi, who had the sneaking suspicion that maggots come from flies instead of spontaneously generating. In a series of experiments in 1668, Redi left meat to rot in closed and open flasks, and then buried still more. Of course, maggots appeared in the open flasks, but not in the closed ones or on the buried meat. Not content to stop there, he added another flask of meat but covered this one in a fine Naples veil, which allowed air flow while still keeping flies out. Maggots did indeed appear—squirming along the veil, longing to reach the meat.

Still, though, the theory of spontaneous generation would not die. And even as tiny worlds finally came into view in the 17th century with the introduction of the microscope, spontaneous generation simply adapted to the invention. In the mid-1700s, naturalist Georges-Louis Leclerc, Comte de Buffon (he seems like the type who would have gotten uppity if I didn’t use his full name, so there it is) put forth perhaps the most fanciful imagining of spontaneous generation yet.

A body, he said, is molecules organized like a mold. But after death these molecules are liberated from the body through putrefaction, then “captured by the power of some other mold.” The organic molecules are still full of life and are always active, and “rework the putrefied substance, appropriating coarser particles, reuniting them, and fashioning a multitude of small organized bodies.” Thus we get organisms like earthworms and mushrooms, he claimed.

I will posit that Louis Pasteur wore bow ties because, like me, he was inherently distrustful of regular ties, which are essentially potential nooses you wear out of the house each day, just begging to be slammed in a taxi door.

Such did spontaneous generation evolve from oysters magically emerging from mud to focus on the tiny building blocks of living things. That is, until Louis Pasteur, that master of microbes, stepped in to put it down for good. Speaking at the Sorbonne Scientific Soirée of 1864 he went after proponents of spontaneous generation . Hard .

He was responding in particular to the experiments of naturalist Félix-Archimède Pouchet, director of the Rouen Museum of Natural History, who spurned germ theory —which was all the rage at the time—in favor of spontaneous generation. Pouchet had boiled water in a flask, killing off the microbes, and added hay he'd sterilized by heating to the point of carbonization, then immediately sealed the vessel to prevent contamination. Still, his water grew muck, ostensibly demonstrating “beyond the shadow of a doubt, the existence of microscopic creatures that entered the world without germs, and thus without parents resembling themselves,” in the sardonic words of Pasteur.

Pasteur argued that airborne microbes had fallen into Pouchet’s mixture in the time it took to seal the flask after boiling it. In his own experiment, Pasteur filled two long-necked flasks with meat broth. The first he brought to a boil as-is to kill off any existing microbes. Then he heated the neck of the second and bent it so that theoretically no airborne microbes could fall in, then brought that flask to a boil as well. As he predicted, the first exploded with growth after only a few days. The second remained “completely unaltered, not just for two days, or three, or four, or even a month, a year, three years, or four!”

Just because you couldn’t see life, it turns out, doesn’t mean that it isn’t there. Speaking to the soirée’s learned scientists, Pasteur triumphantly claimed that “the doctrine of spontaneous generation will never recover from the mortal blow inflicted by this experiment.”

Indeed it didn’t. And nor did Pouchet’s reputation, really (a Britannica entry that calls your ideas “ mere curiosities ” isn’t exactly what you’d call a glowing endorsement). The germ theory he so fervently attacked has helped science save the lives of countless people, thanks in no small part to his rival’s pasteurization techniques. Let’s appreciate Pouchet, though, for his biggest contribution to science: pissing off Pasteur. We all have our purpose, I suppose.

Reference: Brack, A. (1998) The Molecular Origins of Life. Cambridge University Press

Famous Scientists

Jan Baptist von Helmont

Jan Baptist von Helmont was one of the early brilliant minds in the modern period of Flemish chemistry, physiology, and medicine. Sometimes, he is considered as the “founder of pneumatic chemistry” and today he is remembered by modern generations in the field of medicine for his thoughts on spontaneous generation, how he introduced the word “gas” to the scientific vocabulary, and his famous 5-year tree experiment.

Early Years and Background

Born on the 12th day of January in 1580, Brussels, Belgium, Jan Baptist von Helmont was a member of one of the noble families. He was the youngest of the five children of Christiaen van Helmont, a public prosecutor, and Maria van Stassaert. He obtained his education at the Catholic University of Louvain and gained his philosophy degree in 1594. There, he also explored the many different fields of science. However, he found no satisfaction in them and in the end he focused his works on medicine. He obtained his medical degree in 1609 after ten years of travels and studies.

Helmont interrupted his studies with some travelling through England, France, Italy, and Switzerland where he gained practical medical skills. In 1605, he practiced medicine in Antwerp during the time of the great plague. Four years later he obtained his doctoral degree for his courses in medicine. Having finished his education completely, he then married Margaret van Ranst, who also came from a noble family and the couple lived in Vilvoorde, an area near Brussels. They had at least five children, and because of the inheritance his wife had, he was able to comfortably retire early. Helmont occupied himself with various chemical experiments and “exploring the kingdom of plants, animals and minerals through careful examination”, until his time of death.

Helmont is sometimes referred to as the founder of pneumatic chemistry. This is because he was the very first to understand and acknowledge that there are certain gases which are different from atmospheric air. He claimed the word “gas” to be his own invention, and he perceived how what he called as “gas sylvestre” which is produced from burning charcoal is also the same gas present in fermented food. This same air was what he claimed to be the cause of caves having irrespirable air.

What makes this man of science interesting is that he was one of the disciples of Paracelsus, an alchemist and a mystic, these two fields which are usually contradictory to what “science” really is. Most probably because of this, Helmont believed that air and water are the two most primitive elements. He explicitly denied fire to be an element, and stated that earth also is not an element since it can be reduced to water.

5-year plant experiment

From these thoughts and beliefs, Helmont conceived the 5-year plant experiment.

He planted a willow tree in 200 pounds of dry soil and he gave the tree nothing but water for five years—the soil remaining basically the same throughout the time of the experiment. Over the course of 5 years, the willow tree reached its maturity taking in what it was given, and in the end it totaled 169 pounds.

Because of this finding, Jan Baptist von Helmont argued that the growth, change in weight, accumulation of bark, and roots had been formed based on the supply of water alone.

Bodily Processes

Helmont believed in the old idea that bodily processes have fermentative characteristics, but compared to any experimenters who came before him, applied it in more elaborate and conclusive means. He perceived how digestion, nutrition, as well as internal movement related to these procedures are caused by ferments which help convert the “dead food” into what the body can use to support its living flesh.

Also concerning digestion, he suggested that food consumed is digested by the heat from the body. However, if this was the case, according to him, how are the cold-blooded animals able to digest their food with something as heat? This was where the fermentative properties came in. He believed that there are chemical agents inside the body which bring about the fermentation and convert food in the stomach into usable energy.

This idea of Helmont is very much similar to today’s modern concept of the role of enzymes in the body.

Being a disciple of Paracelsus, his scientific thoughts also had their own indications of still having mystic and alchemical ideas behind them. He introduced complicated supernatural systems in the body. These included the “archei” which was said to preside over the direct affairs of one’s body and the archeus which controls the different “subsidiary archei”. He considered that diseases were caused by certain affections observed in the different “archeus” which he called “exorbitatio”.

Helmont believed that remedies act by bringing back the balance that the body needs.

Combining these ideas and his knowledge in medicine, he made unique yet effective deductions. One example was how acidity caused by digestive juices can be remedied by alkalis. Because of this thought, he was one of the forerunners of the iatrochemical school (provides chemical solutions to diseases and medical ailments).

He contributed to the field of medicine by applying the different chemical methods he knew for the preparation of certain drugs.

Religious Views

Above what he called the archeus, Helmont also believed in the presence of a person’s sensitive soul. According to him this is the shell or husk of one’s immortal mind and before “the Fall,” a person’s archeus obeyed the immortal mind.

Apart from the archeus, Helmont also believed in certain governing agencies which resembled the archeus, one of which is “blas” or motion. He particularly believed that there is blashumanun or blas of the humans, and blasmeteoron or blas of meteors. Meteors do, after all, have their own gas and even have motion, which is why his belief about “blas” appeared to be something that is not based on just whim alone.

Helmont was a fervent observer of nature, and with his education as well as other beliefs, his contributions transcended his time and wrote his name in history.

Helmont published several works: De magnetica vulnerum curation (About the Magnetic Healing of Wounds, 1621), Supplementum de Spadanis fontibus (Additional Information on Spa Waters, 1624), Febrium doctrina inaudita (A New Theory of Fevers, 1642) and Opuscula medica inaudita (New Medical Tracts, 1644).

Jan Baptist von Helmont died on 30 December 1644, aged 64. His son, Francis Mercury van Helmont (1614-1699), become a famous physician himself and a pivotal figure in the dissemination of his father’s ideas.

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Jean Baptiste van Helmont was the founder of the iatrochemical school which looked to chemical explanations of vital phenomena. He was a man of great intellectual curiosity and studied philosophy at Louvain. Disappointed with the content of the course he turned to law and after further disappointment decided to study medicine.

Van Helmont’s teaching revolved around two terms, Blas and Gas. He was much influenced by the doctrines of Paracelsus …

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Wexler P, editor. Toxicology in the Middle Ages and Renaissance. London (UK): Elsevier/Academic Press; 2017 Mar.

This chapter is an author manuscript version first made accessible on the NCBI Bookshelf website July 23, 2018.

Toxicology in the Middle Ages and Renaissance.

Jan baptist van helmont and the medical-alchemical perspectives of poison.

Georgiana D. Hedesan .

This chapter discusses Jan Baptist Van Helmont’s (1579-1644) views on poison in light of his medical alchemy. First, it argues that his approach was fundamentally influenced by the theories of ‘universal poison’ and ‘potent poison’ developed by Theophrastus von Hohenheim, called Paracelsus (1493-1541). Paracelsus’s ideas supported Van Helmont’s own views that medical alchemy was the only key to curing all diseases and poisons. At the same time, Van Helmont sought to set these concepts more clearly in a Christian framework, and also used them to launch a scathing attack on Galenic medicine and practices. Moreover, Van Helmont used poison theory to advance his belief in the existence of a universal solvent Alkahest that could extract medical essences out of any being. The Alkahest could then be used to construct an all-powerful universal medicine that proved God’s special providence to mankind.

In his masterpiece Ortus medicinae (1648), the Flemish polymath Jan Baptist Van Helmont (1579-1641) recounted his meeting with a mysterious Irish alchemist named Butler. Butler was in the possession of a ‘little stone’, lapillus , a wondrous alchemical medicine that could cure any disease by touching it with the tip of one’s tongue. Van Helmont was himself given this cure, which, he says, healed him of a slow poison given by an enemy, who confessed his guilt on his deathbed ( Van Helmont, 1652 , p. 469). As he pondered the lapillus and its contents later on, Van Helmont compared its action with that of viper venom, which also acted instantly and in very small quantity (Ibid, p. 474). Thus he envisaged snake poison and Butler’s lapillus as polar opposites. But Van Helmont was not content with alchemy’s action being just as powerful as that of poison, and was eager to affirm its superiority: alchemical medicine could overcome any type of disease or poison. This chapter analyzes how Van Helmont used the notion of poison and poison theories to legitimize the pursuit of medical alchemy. In doing so, he developed his ideas in light of those of Theophrastus von Hohenheim, called Paracelsus (1493-1541), the maverick Swiss physician who initiated a highly influential, if controversial, movement of medical alchemy.

Van Helmont’s Paracelsian Legacy on Poisons

Van Helmont was an heir of Paracelsus’s thought and movement, even if in his later years he went to lengths to distinguish himself from the Swiss physician. While in his early writings, Van Helmont had praised Paracelsus as the restorer of true medicine, by the time most of the Ortus medicinae was written (between 1637-1644), Van Helmont was keen to affirm himself as a uniquely original philosopher who alone had come into the possession of the true ‘Christian philosophy’. Indeed, his wish was to create a new synthesis between Christian thought and natural philosophy, which would rely on the Bible and alchemy as the main pillars of its ideas (Hedesan, 2016a).

Van Helmont was a keen reader of Paracelsus, and had inherited his framework in regards to poison. As I have shown elsewhere, the Swiss physician had developed highly complex theories of poison (Hedesan, 2016b). Perhaps the most important was his theory of universal poison, which argued that all things contained poison within them – as Paracelsus put it, nothing was free from poison. This view was later refined by a ‘potent poison’ theory, according to which some beings have more poisonous power within them than others. Both of these theories had a strong alchemical undertone, since they argued that only alchemy was able to remove the poison within things and hence provide powerful medicine for the sick.

By comparison to Paracelsus, Van Helmont did not develop extensive poison theories. However, as will be seen, he was influenced by the universal poison and potent poison theories of Paracelsus. This took idiosyncratic forms as he tried to reconcile then with his own specific worldview and speculation. Moreover, his perspective on poisons was deeply tied in with his sharp criticism of Galenic medicine and his supreme faith in the power of medical alchemy.

• Universal Poison in a Christian Perspective

In his writings, Paracelsus had strongly advocated a Christian approach to philosophy and medicine, but his theory of universal poison seemed to stand at odds with it. How was it possible that a benevolent Christian God would permit the existence of poison in all things? Paracelsus attempted to answer this by formulating a complex theory of how things were good in their essence, but ambivalent in relation to other things (Hedesan, 2016b, p. [3]). This was an ingenious theory, but did not completely solve the problem. Nor could he explain precisely why some things were more poisonous than others.

As a Christian medical alchemist and Paracelsian follower, Van Helmont faced a similar conundrum. The theory of universal poison was powerful and appealing because it legitimized medical alchemy, confirming the fact that it alone was able to separate the good from the evil in things. Van Helmont could not give up on it, but in order to advance it, he had to answer the same question that plagued Paracelsus.

In Ortus medicinae , Van Helmont did his best to clarify this. In a typical move, he expressed his theory in terms of a biographical quest. He had long observed that ‘if we investigate in depth, there is hardly anything in nature that does not have poison secretly mixed in itself’ ( Van Helmont, 1652 , p. 373). Even roses and violets hide poison within, as all things contain impurity, residue or crudity. We can recognize in this an enunciation of Paracelsus’s universal poison theory.

As a good Christian, Van Helmont finds himself wondering what the situation was before the Fall of Man itself. He considered that these poisons could not harm Adam before the Fall, because he was immortal by the Tree of Life; Van Helmont also pondered that perhaps, the snake notwithstanding, Paradise was free of them. Poisons could only be found in the ordinary world outside of Paradise.

This account raised several issues - Why were there so many poisons in the (non-paradisiacal) world in the first place? And how could he reconcile the universal poison view with the fact that the Bible clearly said that everything was made good in itself? Van Helmont confesses he had grappled with these questions for a long time.

Luckily, he maintains, alchemy came to the rescue and shed a ray of light. In the laboratory, Van Helmont discovered that poisons can be changed by ‘our small labor’ (parvo nostri studio) into effective medicine. Even more, importantly, the more horrid the poison was, the more powerful the remedy. This latter view concurred with Paracelsus’s ‘potent poison’ theory.

Thus, poisons were not ultimately evil, but good in their essence. Van Helmont goes further: he postulates that God was not responsible for death, disease or evil; man had created these because of his Sin. Van Helmont envisaged the Fall as having dramatically damaged the constitution of Adam. It is not that poisons were harmful, but that the human body had become imperfect and could be poisoned. Thus the Fall did not alter the ontological goodness of things, but many poisons, due to their natural strength, were subsequently able cause damage to the inferior bodies of human beings.

Van Helmont concluded that goodness lay just below the poisonous husk ( siliqua ), a fact which was confirmed, he says, by a chance happening. Working on wolfsbane ( aconitum ) one day, he touched the alchemical solution he had prepared with the tip of the tongue. He soon felt his head heavy and eventually fell into a strange state of stupor, where he felt he understood everything very acutely and that this clarity was located on top of the stomach. This gave him the conviction not only in the goodness of apparently evil things, but also that there was great power in poisons, if only their venomous side were removed.

In fact, he thought that the Bible confirmed this, since Ecclesiasticus 38:4 stated that God had created medicine out of the earth. 1 Van Helmont also pondered that the goodness of God must always be stronger than illness and disease. This is already seen, he notes, in the swift and effective action of a famous antidote against snakebite called Orvietan ( Van Helmont, 1652 , p. 471; on Orvietan, see Catellani and Console, 2005 ). Yet it was much more prominent in the lapillus of Butler, which cured all diseases by touching it with the tip of the tongue or by applying dermally. Van Helmont had no doubt that alchemy held the key to true medicine, and contrasted the alchemical processes with the Galenic approach to poisons.

Van Helmont’s Criticism of Galenic Purgatives

In Van Helmont’s time, the majority of physicians followed the Galenic framework, which at this time incorporated medieval Islamic and Latin developments. 2 Galenic medicine was based on the doctrine of the four humors (blood, yellow bile, black bile, and phlegm), which regulated the body. Disease arose when these bodily fluids were imbalanced, and the ‘balancing’ act was done by tempering or purging the offending humor. Common treatments included taking medicines extracted out of plants (usually referred to as ‘simples’) or bloodletting.

In Ortus medicinae , Van Helmont launches a withering attack on the Galenic pharmacopoeia. First, he notes that many plants have a faculty that is stronger than that of the human, thus becoming poisonous to the body. Consequently, most Galenic physicians either reject them altogether, or seek to correct them by inappropriate means ( Van Helmont, 1652 , p. 459). As he points out, correction by boiling does not just remove the poison but also the remedy. For instance, scammony 3 boiled or treated with acids loses its strength (Ibid, p. 374).

Such boiled ‘medicines’ are ineffective, but at least they are harmless; yet other Galenic corrections are downright dangerous for human health. Van Helmont gives the example of the physicians’ erroneous treatment of Spanish-Italian general Carlo Spinelli, who was given a solution of white hellebore corrected with anise seed. This provoked a half-hour vomiting bout that ended in convulsion and ultimately death (Ibid, p. 374).

Van Helmont considered that the problem with Galenic physicians was that their attitude toward hard purgatives, particularly laxatives, was inconsistent and hypocritical. While Galen had thought of laxatives to be poisonous, and most Galenic physicians would admit that they are dangerous, they continue prescribing them in ‘corrected’ form. When things do go wrong, they blame the dose, the correction, the solution, the apothecary or even his wife for it (Ibid, p. 755).

The attraction of Galenic physicians to purgatives was borne out of a fundamental error: they falsely believed that excrements induced by purgatives were bad humors. Van Helmont denied that the excrements resulting from laxatives were humors at all, but putrefied matter caused by poisoning. Again, Van Helmont’s evidence lies in personal testimony, told, in Helmontian style, with rueful humor. 4 When he was young, he recounts, he had touched the glove and hand of a lady infected with scabies, and got the scabies too. At the time, Galenic physicians did not recognize the disease as being contagious, but instead attributed it to a distemper caused by the overheating of the liver. Young Van Helmont, eighteen at the time and a student of medicine, called in two leading physicians of Brussels to obtain their recommendation, ‘half-glad’ to get experience in medical treatment. The physicians diagnosed him with an excess of inflamed bile and of salty phlegm, which caused damaged blood production in the liver. First, they prescribed bloodletting to cool the liver. A concoction was then offered to eliminate the yellow bile and phlegm from the body. Since that also did not work, Van Helmont took laxative pills of fumaria , which made him evacuate many stools. Naively, he felt pleased by this as he thought his corrupted humor was thus being eliminated. He took another round of laxatives after two days, and then another after three. Having eliminated so many stools as to ‘easily fill two buckets’, Van Helmont felt seriously weak: ‘I who previously were healthy, vivacious, full of strength, light in jumping and running, I was now emaciated, my knees were trembling, my cheeks collapsed, and my voice was hoarse’ ( Van Helmont, 1652 , p. 756). Nor did his scabies go away with the laxative. At that point, the youth started wondering where all those humors were coming from. Surely, he calculated, there was not enough room in the bowels, in the head or in his chest to contain so much humor. Eventually, upon reflection, Van Helmont concluded that the so-called humors were not originally present in his body, but were formed by the action of the laxative. This conviction acquired, the young man grew increasingly critical of traditional medicine. As for laxatives, he concluded that ‘it is indubitable that laxatives contain hidden poison, which has made thousands of widows and orphans’ (Ibid, p. 757).

Eventually, Van Helmont claimed that laxative action was simply a manifestation of their poison. The mechanism whereby poisons act within the body is the following: once ingested and received in the stomach, they ferment, dissolve anything found there, and then putrefy them. This would still be fine if the laxatives were to dissolve excrements, but they actually destroy the vital juices of the body. Thus, they corrupt the purified blood out of the vena cava , contaminate it with their poison and dissolve it by means of a fetid cadaverous ferment (Ibid, p. 420). This leads to a disturbance of the body that persists long after the laxative was taken, and often in spite of any astringent medicine. Hence, he concludes, laxatives ‘are poisons to us, not to the excrements’ (Ibid, p. 383).

Van Helmont is also critical of the common belief in his period that laxatives could ‘clean’ the body and supposedly preserve it from disease. He gives the anecdotal example of a Privy Counsellor of Brabant, who took aloe pills to maintain his health intact. These pills were corrected to the point they were useless, and had no effect. When the Counsellor complained of the lack of success to his physician, the latter gave him stronger pills of an undisclosed type. These had such a harsh effect that the Counsellor died miserably, leaving behind eleven children (Ibid, p. 756). Van Helmont blamed the faith in laxatives squarely on Galenic practices, and on the false belief in humors.

• The Alchemical Solution

As already mentioned, Van Helmont believed, along with Paracelsus and other Paracelsians, that the essence of all things was pure and good. This belief was articulated in Van Helmont’s theory of the primum ens (‘first being’), which was drawn from pseudo-Lullian and Paracelsian precedents. In Van Helmont’s view, if an entity could be returned to its primum ens , it could re-acquire its original goodness, or medical quality. This was particularly important in the case of poisons, which had a stronger virtue than others.

Van Helmont expressed the alchemical process of obtaining the medical essence as an ‘inversion’. A poison should be ‘inverted in its core’ ( in sui radice introverti ): colocynth, for instance, could ‘invert’ its laxative quality, which can then be used to cure chronic disease ( Van Helmont, 1652 , p. 374).

This, Van Helmont adds, was familiar to Paracelsus, who knew how accomplish the inversion for a medicine called antimonial tincture of lily. Yet, the Flemish physician maintains, Paracelsus did not know that this could be done for all poisonous plants and animals by using the ‘greater circulated salt’ solvent. Indeed, all things lose their poison and acquire medical power if they are reduced to their primum ens (Ibid, p. 374).

The ‘greater circulated salt’, the same or similar as the universal solvent Alkahest, emerges as the primary substance capable of bringing about the medical inversion of poisons. 5 Van Helmont eloquently praises this alchemical key as that ‘which returns all things into the primum ens , preserving their native endowments, erasing the original blemishes of bodies; once their inhuman ferocity is removed, they become capable of giving birth to great and inexplicable powers’ (Ibid, p. 387). Ultimately, the Alkahest can lead to the creation of the supreme universal medicine, Butler’s lapillus , which demonstrates the special providence of God toward mankind.

Thus, alchemy provides the key to remove poison from all things. However, not all essences are equally useful for the human body. Van Helmont supports the use of poisonous plants in medicine, but is ambivalent about animal poison. He believes, along with most medical alchemists of his time, that metals and minerals ordinarily deemed poisonous, like antimony and mercury, could be exploited for great health benefits. Yet he absolutely condemns the internal employment of arsenic in any form. Finally, he extols the virtues of poisonous ‘sulphurs’ of metals and minerals, which can be transformed into medicines that are particularly comforting to the body. Van Helmont lists many potentially deadly diseases healed by means of sulphurs (Ibid, p. 460).

• Conclusions

Van Helmont’s interest in poisons was deeply linked with his belief in the power of medical alchemy. For the Flemish physician, alchemy was the apex of all knowledge, and was most effective in providing cures to diseases previously – and erroneously – thought to be incurable.

Undoubtedly, Van Helmont’s understanding of alchemy derived from Paracelsus and Paracelsianism. This was particularly evident for poisons. Similar to Paracelsus, Van Helmont thought that poisons acted as a link between natural philosophy and medical-alchemical practice. They were tied with a grand vision of good and evil in the world and with an attempt at explaining the presence of evil in Christian terms. They were also meant to justify peculiar, and controversial alchemical practices.

We have seen that Van Helmont fundamentally subscribed to Paracelsus’s universal poison theory, and the associated potent poison theory. Like Paracelsus, he believed that things had a ‘poisonous’ and a ‘medicinal’ side. He also believed the alchemy could separate these two aspects so that only the medicinal side remained. Finally, he also agreed that some substances have more power than others, and these hid great medicine within.

If the two men disagreed on anything, it was on the details of the philosophy behind the theory. Paracelsus sought universal theories that integrated man with nature. Van Helmont preferred to focus his attention on man exclusively, whom he found responsible for everything from death to disease and poison. Van Helmont’s philosophy was essentially a human philosophy, targeted and justified by medicine.

• Catellani P, Console R. Orvietan, A Popular and Controversial Panacea. Pharmaceutical Historian. 2005; 35 :11–19. [ PubMed : 15977377 ]
• Chisholm, Hugh, ed.: Scammony .  Encyclopædia Britannica , ed. 11, Cambridge, 1911, Cambridge University Press.
• Hedesan GD (a): An Alchemical Quest for Universal Knowledge: The ‘Christian Philosophy of Jan Baptist Van Helmont (1579-1644), London, 2016, Routledge.
• Hedesan GD (b): Alchemy, Potency, Imagination: Paracelsus’s Theories of Poison. In Cunningham A and Grell, OP: Poisons in European History, London, 2016, Routledge, pp. [1-17] (accepted, in press).
• Porto P. ‘ Summus atque felicissimus salium’ : The Medical Relevance of the Liquor Alkahest. Bulletin of the History of Medicine. 2002; 76 :1–29. [ PubMed : 11875242 ]
• Siraisi, Nancy G: Medieval and Early Renaissance Medicine: An Introduction to Knowledge and Practice, Chicago, 1990, University of Chicago Press.
• Van Helmont JB: Ortus medicinae, id est, initia physicae inaudita, ed. 2, Amsterdam, 1652, Elzevir.

All translations from Latin are my own.

The whole passage runs: ‘The Lord hath created medicines out of the earth; and he that is wise will not abhor them.’ Ecclesiasticus (Jesus Sirach) is considered a Deuterocanonical book in the Catholic faith and apocryphal in the Protestant one. In the period, Ecclesiasticus was popular with medical alchemists, as they believed it justified their doctrines.

On medieval medicine and early Renaissance medicine, see Siraisi (1990).

Scammony ( Convolvulus scammonia ) is a perennial plant native to the countries of the eastern part of the Mediterranean basin; it grows in bushy wasteland from Syria up to Crimea, its range extending westward to the Greek islands. The juice of scammony has a powerful purgative effect. See Chisholm (1911).

The story is first told in the treatise ‘De febribus’, p. 756 (published first in 1642), and later in ‘Scabies et ulcera Scholarum’, pp. 255-256.

On the Alkahest, see also Porto (2002), Hedesan (2016a, pp. 177-182).

Creative Commons-Attribution-NonCommercial-NoDerivs (CC-BY-NC-ND). This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Monographs, or book chapters, which are outputs of Wellcome Trust funding have been made freely available as part of the Wellcome Trust's open access policy

• Cite this Page Hedesan GD. Jan Baptist Van Helmont and the Medical-Alchemical Perspectives of Poison. In: Wexler P, editor. Toxicology in the Middle Ages and Renaissance. London (UK): Elsevier/Academic Press; 2017 Mar.
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