(Louis Philippe Joseph d'Orléans, duc de Chartres, later duc d'Orléeans

Leçons de mathématiques données à S. A. Monseigneur le duc de Chartres par Mr Dumesnilurry, ingénieur et professeur de mathématiques le 15 May 1759



Manuscript, 4to (8 3/4 x 10 1/2 in.; 236 x 190 mm), title-page, 2 leaves for table of contents, 281 leaves written on both recto and verso containing lessons given to the Duc de Chartres at the age of twelve by the engineer and professor of mathematics Mr. Dumesnilurry (or Du Mesnil-Urry),  the lessons range in scope from addition and other simple operations to geometry, more complex algebra (extraction of  square and cubed roots) , trigonometry, logarithms, rules of accounting. Full red morocco, French filleted panels with fleur-de-lys cornerpieces, the spine smooth, lettered gilt and  ornamented with gilt fleur-de-lys, fleurons, stars and other small tools, supralibros of the Duke de Chartres, later the Duke d'Orléans and the future Philippe Egalité. 

A fascinating testimony to the passion for education shared by the Duke de Chartres with his father, who chose for him the best pedagogues of the day such as Etienne Lauréault de Foncemagne and Carmontelle.   A progressive in his moral views as well as in his political views, he accepted his mistress Mme de Genlis to assert herself in quality of "governess" for the education of his children (among them the future King Louis Philippe).

During the Revolution, he accepted the appellation Citoyen Égalité (Citizen Equality) conferred on him by the Commune. He was elected the twentieth and last deputy for Paris to the National Convention where he voted in favor of the death sentence for his cousin Louis XVI.  Many citizens viewed  this as an attempt by Philippe to overthrow the crown and seize power himself and his Orléans branch. .

His compliance with republican rules did not save him from suspicion.  When the news of the desertion of his son tthe future Louis Philippe and General Charles Dumouriez  reached Paris, all the Orléans remaining in France, including Philippe Égalité, were arrested on 5 April 1793. First imprisoned in Paris, he was later transferred to the Marseille fort then brought back to Paris in October, during the Reign of Terror. As a member of the royal family  Louis Philippe was shortlisted for a trial, and effectively tried and guillotined in the space of one day on 6 November 1793.

In a perfect state of preservation, this manuscript has survived the vicissitudes of the Revolution, the Empire, and the Restoration of the Bourbons. It was conserved by King Louis Philippe in his library at the Palais-Royal and bears his cachet on the upper corner of page one.