Harcourt, Augustus

Augustus George Vernon Harcourt and William Esson... 

The first non systematic introduction of thermodynamics in Chemical Kinetics is due to the second couple of scientists previously cited Augustus George Vernon Harcourt (1834-1919) and William Esson (1839-1916). Harcourt was an important chemist, member of the Royal society and president of Chemical society, Esson a mathematician and Savilian professor of Geometry. They worked at University of Oxford in a period particularly fruitful for Sciences in Britain. It is the peak of positivism and at the time different sciences, included chemistry, got clearly distinct university courses. Their activity covered a period of fifty years and represented the main passage from natural philosophy speculations to modern scientific reasoning. Influenced by Van t Hoff they will definitively abandon ambiguous terms like Affinity and Chemical Forces. 

Wilhelmy s work remained largely unnoticed until Ostwald drew attention to it over 30 years later. In the meantime, three pairs of workers had performed important work on reaction kinetics and chemical equilibria. They were the Frenchmen Berthelot and Leon Pean de Saint-Gilles (1832-1863), the Norwegians Cato Maximilian Guldberg (1836-1902) and Peter Waage (1833-1900), and the Englishmen Augustus Vernon Harcourt (1834-1919) and William Esson (1839-1916). 

Noteworthy is the work of Augustus Harcourt and William Esson in England between 1865 and 1867. The chemist Harcourt made detailed experiments on the reactions between hydrogen peroxide and hydrogen iodide as well as between potassium permanganate and oxalic acid, paying particular attention to the influence of the reactant concentrations on the rate. The mathematician Esson analyzed his results in terms of differential equations which are similar to the ones used today. Esson was also the first to treat the kinetics of consecutive reactions, a topic we discuss in the next chapter. 

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