Famous mathematician, born at Turin of French parentage; had gained at the age of twenty a European reputation by his abstruse algebraical investigations; appointed director of Berlin Academy in 1766, he pursued his researches there for twenty-one years; in 1787 he removed to Paris, where be received a pension from the Court of 6000 francs, and remained till his death; universally respected, he was unscathed by the Revolution; appointed to several offices, he received the Grand Cross of the Legion of Honour from Napoleon, who made him a count (1736-1813).