Joseph Priestley, the main defender of phlogiston theory against Lavoisier’s new chemistry, was a religious and economic liberal who supported the French revolution, and eventually moved to America, after being targeted by conservative mobs in Britain. A few years after Priestley’s move, at the age of 50, Lavoisier was guillotined by a French revolutionary tribunal, along with dozens of other aristocrats who had been supported by a hated royal taxation authority. The judge himself was executed three months later, and Lavoisier was posthumously rehabilitated a year after that. In his exile, Priestley outlived Lavoisier by ten years, but phlogiston theory was already considered outdated and wrong.
The entire debate surrounding phlogiston had unfolded without basic concepts that we now take for granted, like conservation of energy, or the idea that heat is “energy on the move”. That all came decades later.
“Phlogiston Theory and Chemical Revolutions” argues that, while Lavoisier clarified the concept of a chemical element, phlogiston theory was ahead of its time as a physical theory of chemical interaction. The author’s idea is that phlogiston is now better understood as a property similar to energy (“the Gibbs chemical potential of a material with respect to its oxide”), rather than as a substance.
Joseph Priestley, the main defender of phlogiston theory against Lavoisier’s new chemistry, was a religious and economic liberal who supported the French revolution, and eventually moved to America, after being targeted by conservative mobs in Britain. A few years after Priestley’s move, at the age of 50, Lavoisier was guillotined by a French revolutionary tribunal, along with dozens of other aristocrats who had been supported by a hated royal taxation authority. The judge himself was executed three months later, and Lavoisier was posthumously rehabilitated a year after that. In his exile, Priestley outlived Lavoisier by ten years, but phlogiston theory was already considered outdated and wrong.
The entire debate surrounding phlogiston had unfolded without basic concepts that we now take for granted, like conservation of energy, or the idea that heat is “energy on the move”. That all came decades later.