Johann Baptista van Helmont
1579 - 1644

Noble roots. Johann Baptista van Helmont was born in 1579 in Brussels, Belgium to a noble family.  Van Helmont studied arts at Louvain until 1594, but did not complete a degree.  He next attended the Jesuits' school at Louvain, but left there dissatisfied.  From there he studied the works of the mystics and finally turned to the study of medicine.  After reading and studying the works of Hippocrates, Galen, Avicenna, van Helmont expressed dismay at the lack of useful information they contained. ....all seemed certain and incontrovertible..... the years I had spent were altogether fruitless."1 Van Helmont obtained his MD in 1609 at Louvain.


On Marriage and Chemistry.  In 1609, van Helmont married Margaret van Ranst, also from nobility.  Of her, he wrote:

"God has given me a pious and noble wife.  I retired with her to Vilvorde and there for seven years I dedicated myself to pyrotechny and to the relief of the poor."1

 Another account says:

 "[Van Helmont was] wholly taken up in chemical operations night and day.... he was scarce known in his neighborhood.... nor scarce ever stirr'd out of doors."1

From Alhemist to chemist.  Van Helmont represents the transformation between alchemy and chemistry.  For example, he believed in magic and claimed to have used a small piece of the philosophers stone to convert mercury into gold.  On the other hand, Van Helmont was one of the earliest to use the balance in his chemical work and he believed in the indestructibility of matter.  A century later, the significance of accurate measurements was still not widely appreciated.  Van Helmont knew that metals could be dissolved with acids ('concealed in solution') and reproduced, such as by reaction with another metal.  He established that metals were not destroyed by acid.  Van Helmont referred to himself as a 'philosophus per ignem' (philosopher by fire).  He valued experimental work over philosophical reasoning.

On Aristotle and Water.  Van Helmont rejected the Aristotelian theory of four elements, however, he agreed that air and water were elements.  Air's role was to enhance fires and water, therefore, was the basis for all else.  His famous willow tree experiment 'proved' that water could be converted into other forms of matter.  Van Helmont planted a willow tree in a weighed amount of earth.  After watering it faithfully for five years, van Helmont found that while the tree had gained 164 pounds, the weight of soil was not diminished.  This proved to him that the tree represented water transformed into another substance.

Wild Spirit.  Van Helmont was the first to consider the production of gases during chemical reactions.  He coined the word 'gas' possibly from the word 'chaos.'2  He also noted that gases can explode glass containers and can be condensed into liquids.

"Suppose thou, that 62 pounds of Oaken coal, one pound of ashes is composed: Therefore the 61 remaining pounds are the "wild spirit" which, also being fired, cannot depart, the Vessel being shut.  I call this spirit, unknown hitherto, the new name of 'gas,' which can neither be retained in Vessels nor reduced to a visible form, unless the seed is first extinguished."3

"[If nitric acid is poured on sal ammoniac in a glass vessel which is closed by cement or by melting the glass,] the vessel is filled with plentiful exhalation (yet an invisible one) and however it may be feigned to be stronger than iron, yet it straightway dangerously leapeth asunder into broken pieces."1

[...gas is composed of invisible atoms which can come together by intense cold and condense into minute liquid drops.]1

Gases described by van Helmont.  Van Helmont's extensive study of gases has earned him the honor of being called 'the real father of pneumatic chemistry.'4  Some credit him with the discovery of carbon dioxide (which he called gas sylvestre).  In all, he investigated and categorized a long list of gases, including:

  gases evolved from spa water [now known to be CO2]
  gases produced by burning charcoal [CO2 and CO]
  gases that form in cellars where wine is fermenting [CO2]
  gas from eructions (belches) [CO2]
  the poisonous gas that collects in mines [CO2]
  poisonous red gas [NO2] that is formed when aqua fortis (HNO3) on silver
  gas evolved from aqua fortis (HNO3) and sal ammoniac (NH4Cl) in the cold [Cl2]
  sulfurous gas that 'flies off' from burning sulfur [SO2]
  gases from burning gunpowder which burst closed vessels [CO2, H2O and SO2]
  intestinal gas which is flammable [H2, CH4, H2S and impurities]
  gases evolved in putrefaction [H2, CH44, H2S, organic amines and many others]

Lived to age 65.  At age 60 van Helmont described a near-death experience in which he accidentally poisoned himself with gases from burning charcoal.  The symptoms given suggest he had CO poisoning.  Van Helmont died December 30, 1644.

Lasting accomplishments.

  use of the balance and belief in the conservation of matter

  first to recognize and characterize gases, coined the word 'gas.' (The word 'gas' was not used in England until the 19th century because Robert Boyle used the word 'air' in the context of various types of 'air.'

His 1648 book Ortus medicinae established van Helmont as an instrument of transition from alchemy to chemistry.  Robert Boyle was influenced by van Helmont's work.  This book collection of van Helmont's work, assembled and edited by his son four years after van Helmont's death.


1 A Short History of Chemistry, J. R. Partington, 3rd edition, (1957)

2. The Historical Background of Chemistry, H. M. Leicester, Dover, 1956.

3 Oriatricke, or Physick Refined, van Helmont, English language edition, 1662.

4 A Source Book in Chemistry 1400 - 1900, H. M. Leicester, H. S. Klickstein, Harvard University Press, 1968.


(This page last updated 25 September 2001)