Fire analysis in the eighteenth century: Herman Boerhaave and scepticism about the elements

In the eighteenth century, many chemists asserted that chemical operations could not decompose a substance into its natural, constituent elements or principles. One such chemist was Herman Boerhaave (1668-1738), who claimed, following the work of Robert Boyle and Joan Baptista van Helmont, that examples of these alleged analyses were, in fact, not reductions of a body into elements, but rather the rearrangement of its particles by the fire. Since we cannot observe the shape and arrangement of particles directly, he reasoned, any claim regarding the elemental status of a substance was purely speculative and inadmissible in his chemistry. As a result, Boerhaave devised a system of chemistry which, in effect, accepted no elemental substances and which focused on understanding how the chemist's 'instruments,' including fire and chemical menstrua, effected changes in matter. I conclude by showing how Boerhaave's conclusion had ramifications for later developments in chemistry, especially those of the French Stahlians and of Antione Lavoisier.