Page:Biographies of Scientific Men.djvu/24

2 The doctrines of Aristotle, and Byzantine, Egyptian, Arabian, and European writers concerning the "four elements"—earth, water, fire, and air—and other non-scientific theories were swept away by the master-mind of the great Frenchman. Even Priestley, Cavendish, Scheele, Macquer, and other distinguished men could not entirely divest themselves of the phlogistic theory; in fact, Black "was the only chemist of his age who completely and openly avowed his conversion to the new Lavoisierian doctrine of combustion."

In 1764 Lavoisier (having been called to the bar as an avocat) gained the prize awarded by the Government of Louis XV. for the best method of lighting the streets of Paris and other large towns, and elaborate experiments on the subject are to be found in the memoirs of the Académie des Sciences—"the greatest scientific body on earth"—as the illustrious Academy has been called by a distinguished American writer; and in 1768 Lavoisier was elected one of its members. Between that date and 1774 he published many papers on chemical, mathematical, and geological subjects—all of which are remarkable for showing the extraordinary ardour and devotion to science of this truly great philosopher. The accuracy of his work and reasoning powers will be found by referring to two of his papers in the memoirs of the Academy for 1770, in which he refutes the idea, held by many, that water could be converted into earth; and it is remarkable that