Home » Classic Medicine » Chemistry


chemistry alchemy image from New Medical Terms

Alchemists hard at work

The field of chemistry is rooted in alchemy, a naive science and philosophy based on the belief that matter can be transformed from one form to another*. Gentleman-scientist Robert Boyle (1627-1691) formed part of the vanguard that disproved alchemy’s basic premises. Regarded as a co-founder of modern chemistry, his contributions to the field include proving the inversely proportional relationship between the absolute pressure and volume of a gas (Boyle’s law), introducing the scientific method to experimentation, conceptualizing atoms and molecules, and using colored indicators to confirm chemical reactions.

*The holy grail for most medieval alchemists was the conversion of base metals to gold. Alchemists also searched in vain for universal elixirs that would cure all ills and prolong life. 

Robert Boyle's text image from New Medical Terms

Robert Boyle’s text

The 18th century was a fertile period for chemistry and saw the discovery of carbon dioxide, cobalt, nickel, and tungsten. Antoine Lavoisier (1743-1794), the short-lived luminary of pre-Revolutionary France is known as a father of modern chemistry for articulating the law of mass conservation*, for devising a system of chemical nomenclature, and for recognizing basic elements, including oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc and sulfur. He lost his head to the guillotine in 1794.

*Whilst Lavoisier is usually credited with the law of mass conservation (in 1774), other workers–e.g., Mikhail Lomonosov (1711–1765), Joseph Black (1728–1799), Henry Cavendish (1731–1810), and Jean Rey(1583–1645) have been linked to the law. 

By the 19th century, one could throw a stick any place in Europe and hit a handful of chemists making important discoveries. John Dalton (1766-1844) confirmed Boyle’s early musings and formally proposed the modern atomic theory. Jöns Jacob Berzelius (1779-1848), a Swedish chemist and one of Dalton’s disciples, meticulously* measured the weights of over 40 elements and assigned the known elements one- or two-letter symbols–e.g., O for oxygen, Fe for iron, Cu for copper and so on.

Of the many others who made major contributions to the field in the 18th and 19th centuries, two names stand out:

chemistry modern engineering image from New Medical Terms

modern chemical engineering

Amedeo Avogadro (1776-1856), whose law states, under controlled conditions of temperature and pressure, equal volumes of gas contain an equal number of molecules and

Dmitri Mendeleev (1834-1907), who formulated the periodic law and created the current periodic table of elements, using it to correct the properties of some elements and predict the properties of eight later discovered elements.

*He was Swedish, of course he was meticulous 

The 19th and early 20th centuries saw a plethora of discoveries in chemistry that inform current medical thought and practice, including confirmation of Berzelius’s theory of chemical isomerism, which was linked a century later to the thalidomide tragedy; Wm Prout’s classification of biomolecules into the modern groups: proteins, lipids and carbohydrates, which was the founding event of the field of biochemistry; August Kekulé’s proposed structures of organic compounds (most are aromatic and all have at least one hexagonal benzene ring); and Mikhail Tsevet’s invention of chromatography.