[Denis Ballière (1729-1800)].

Born in Paris in 1729, Ballière got his graduation from the University of Sorbonne as bachelor of arts in 1746. His uncle Charles Delaisement practised as apothecary in Rouen and Ballière obtained there his mastership in 1756. Concomitantly, he composed the poetry and music of several opéras-comiques in the style of pastorales, which were performed with success in Rouen and Paris theaters. He was a fine writer and a real erudite. As well, his capacity in mathematics lead him to set up a theory applicated to both acoustic and music. In 1764 was published his Théorie de la musique in which he analysed the works of Descartes, Sauveur, Wallis, Tartini, Rameau, d'Alembert and Diderot. Rousseau greeted this work with consideration. When his uncle died in 1768, he fully engaged in the pharmaceutical profession. Since 1754, he had been a member of the Académie de Rouen, in which he was scientific secretary in 1769 and president in 1784, publishing different works among them its Essai sur les problèmes de situation - regarding the probability calculus - can be mentioned. In 1779, he translated into French John Ellis's book on Mangostan. He died in Rouen in 1800.