Alchemy has been marginalised by historians, jotted as a footnote beside a small cartoon of Merlin – and William Newman is not happy. In Atoms and Alchemy he puts forward his case that it was the practitioners of ‘chymistry’ from the Middle Ages onwards who discovered the key components of what was to become Robert Boyle’s mechanical theory – and the beginnings of chemistry – in the 17th century. In particular, Newman highlights the work of Daniel Sennert, a German academic who in 1618 declared that since the transmutation of metals had been seen in nature, “the same can also be done by art”. This was at a time when all matter was believed to be made of the four Aristotelian elements: fire, earth, water and air.

Benefiting from the discovery of mineral acids, Sennert reduced metal alloys to their “pristine state” (the separation of the constituents) to arrive at a “corpuscular” theory. One pivotal experiment was to dissolve silver in nitric acid, filter the solution through paper and retrieve the silver by adding oil of tartar and then heating the curdled silver carbonate to once again form the metal. The same experiment was appropriated holus-bolus by Boyle 30 years later. But where Sennert used experiments to disprove the Aristotelian theory, Boyle used the same experiments to prove the existence of atoms, and hence Newman’s claim that the foundations for Boyle’s matter theory were laid by Sennert. He also got close to what we know as chemistry today by suggesting the oil of tartar is attracted to the acid more than the acid is attracted to the silver, using the concepts of diakrisis (separating) and synkrisis (joining) to explain his results.

Newman’s book is engrossing and he writes with a warm scholarly flair. It is easy to imagine yourself in the gallery of an ancient courtroom as the author postulates to the jury using logic and laws that have since, of course, been made largely redundant by the scientific revolution. But Newman’s case isn’t against Boyle; it’s against some of the historians of science. It made me wonder how many great thinkers have gone by the wayside throughout the ages, and then made me thankful for a writer such as Newman, whose passion for the subject is something to share.