A 1781 handwritten letter by George Washington lamenting the Continental Army's failure to capture Benedict Arnold has sold for $100,000.
The lot was among the highlights of Heritage Auctions' November 4-5 manuscript sale in New York.
Arnold is one of the most notorious traitors in American history. In 1780 he relinquished control of West Point fort to the British and switched sides.
For the rest of the war he proved a thorn in Washington's side, regularly conducting raids against American forces in Virginia.
The letter is addressed to major general Alexander McDougall and relates Washington's annoyance that Arnold was saved by superior British sea power during the Battle of Cape Henry in March, 1781.
Washington writes: "The Expedition against Arnold has failed-after the favourable moment (occasioned by the disability of part of the British Ships in Gardner's bay) was suffered to pass away, I never was sanguine in it-but the object being great, the risk was warrantable.
"The attempt of the Chevalier Des Touches at the time he sailed was bold & enterprising-for this, and political reasons; and because I know it will be grateful to the French Genl. & Admiral, I take the liberty of hinting to you the propriety (if it is not already done) of Congress paying them a compliment on the occasion.
"It may have a happy effect which is the only apology I can offer for the freedom of suggesting it."
The sale also included a handwritten copy of Abraham Lincoln's second inauguration speech that sold for $2.2m.
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