Note 169 — Chapter VI · CHEMICAL EQUILIBRIUM. THE LAW OF MASS ACTION
Reading edition
Since in any chemical action, which has not reached a condition of equilibrium, the concentrations of the reacting substances change continuously, the relation between the velocity of the action and the concentrations, for any moment, is found by the application of the calculus to the experimental data. (Cf. Elements of Calculus, by Young and Linebarger (1900), 168, 181, 240; Mellor, Higher Mathematics for Students of Chemistry and Physics (1902), 197.)