In 1754 he was a member of the chambre royale which sat during an exile of the parlement; in 1755 and 1756 he accompanied Gournay, then intendant of commerce, in his tours of inspection in the provinces, and in 1760, while travelling in the east of France and Switzerland, visited Voltaire, who became one of his chief friends and supporters.
The principal navigation company on the upper Danube is the Societe Imperiale et Royale Autrichienne of Vienna, which started operations in 1830.
At Mittau was realized his cherished plan of marrying Madame Royale, daughter of Louis XVI., to the duc d'Angouleme, elder son of the comte d'Artois.
The royal party included, beside the king and queen, their daughter Marie Therese Charlotte (Madame Royale), the king's sister Madame Elisabeth, the valet Clery and others.
Upon the disgrace of Vauban, whose Dime royale had much in common with Boisguilbert's plan, Boisguilbert violently attacked the controller in a pamphlet, Supplement au detail de la France.
