NEW YORK CITY — A dress sword that belonged to Benjamin Franklin will hit the block at Christie’s on September 20 as part of its important American furniture, silver, Outsider and folk art sale. The sword bears a French inscription translated to “Sword worn by Benjamin Franklin in the battles fought in America in the cause of Liberty. / He then gave it to his friend P.J.G. Cabanis.” Christie’s writes, “Both men of the Enlightenment, they shared a love of scientific study (Cabanis was a member of the prestigious Académie Française, and Franklin was a foreign associate) as well as a broader interest in humanism, morality and liberty.” Howard Dixon, Christie’s specialist in arms and armour said, “Franklin was very much the father figure that Cabanis looked up to.”  The sword comes to market from the Cabanis family and will be offered with an estimate of $200/300,000. For more information, www.christies.com or 212-636-2000.