884634 Jean le Rond d\'Alembert at the salon of Mme du Deffant and Mlle de Lespinasse, from \'Vies des Savants Illustres\', by Louis Figuier (engraving) by French School, (19th century); Bibliotheque Nationale, Paris, France; (add.info.: Jean-Baptiste le Rond d\'Alembert (1717-83) was a French mathematician, mechanician, physicist, philosopher, and music theorist. Until 1759 he was also co-editor with Denis Diderot of the Encyclop矇die. Marie Anne de Vichy-Chamrond, marquise du Deffand (1697-80) was a French hostess and patron of the arts. Jeanne Julie ?l矇onore de Lespinasse (1732-76) owned a prominent salon in France. Julie moved into Madame du Deffand\'s apartments in Convent of St. Joseph in 1754, location of the glittering salon that attracted famous diplomats, great ladies, philosophers and politicians. ); 穢 Archives Charmet.