Most people don’t picture a spy holding a basket of laundry. But during the American Revolution, Anna Strong helped run George Washington’s Culper Spy Ring—and she did it from her backyard.

Anna’s weapon of choice? A clothesline.

She lived in Setauket, Long Island, near the British-controlled coastline. Her job was to send coded signals to fellow patriots about secret message drops. Instead of notes or whispers, she used laundry hung in plain sight.

• A black petticoat signaled a message was ready.

• The number of white handkerchiefs told the recipient which cove to retrieve it from.

• It was a low-tech, low-risk system...because no one suspected a woman doing chores could be helping win a war.

Anna's ingenuity helped keep communications flowing between Washington’s spies, without ever touching pen or parchment. It was one of the most effective and invisible systems of the entire spy ring.