[Americana] Lafayette, Marquis de Autograph Letter, signedLa grange, (France), 26 Sept(ember), 1829. One sheet folded to make four pages, 10 x 7 3/4 in. (254 x 197 mm). Autograph letter in French, signed by the Marquis de Lafayette, introducing a business associate, a Mr. Muschietti of Piedmont, to French-American linguist Peter Stephen du Ponceau in Philadelphia, and requesting that Ponceau help Muschietti make business connections in the city; in a postscript, Lafayette makes reference to his friend, the New York politician, Colden D. Cadwallader; addressed by Lafayette on integral leaf, docketed in another hand to same; remnants of red wax seal on integral leaf. Creasing from contemporary folds, scattered small separations along same; two open tears on first leaf, not affecting text; scattered foxing to each leaf.Peter Stephen Du Ponceau (1760-1844) was a noted French-American linguist and lawyer. He came to America in 1777 as an aide-de-camp to Prussian military officer Baron von Steuben, and served as a captain in the American army until 1779, when illness forced him to resign. Afterward he settled in Philadelphia, and served as secretary to Secretary of Foreign Affairs, Robert Livingston. Following the war he became a prominent lawyer, specializing in international law, was a noted intellectual and linguist, and helped translate many Native American languages. He was an active member of Philadelphia's cultural organizations, and served as president of the American Philosophical Society, the Athenaeum of Philadelphia, and the Historical Society of Pennsylvania. He was a founding member of the French Benevolent Society of Philadelphia and the Philadelphia Bar Association. Lafayette and Ponceau corresponded often, with Lafayette keeping Ponceau updated on politics in France.ProvenanceDeaccessioned by the Valentine Museum to benefit collections care, preservation, and future acquisitions