After he defected to the British army, Benjamin Arnold’s first action as a General in the English forces, on January 4th, 1781, was to launch an attack on Richmond. A letter by Thomas Jefferson describing that battle, and how little it yielded to the British, will be a highlight at a New York auction of Revolutionary Americana from the Allyn Kellogg Ford Collection at Swann Galleries. It’s expected to sell for $30,000-$40,000 at the April 17th event.There’s also a letter in the sale from Arnold to Delaware Governor Caesar Rodney. The document predates Arnold’s defection. In it, as a major general in the Continental Army, he answers accusations of war profiteering and claims to have been slandered. “My character,” the soon-to-be traitor writes, “has been most cruelly and unjustly aspersed.” The letter’s estimated at $10,000-$20,000. As it happened, Arnold was acquitted. The following year, when his plan to hand over West Point to the British was discovered, he escaped capture and changed sides.