Blood Chit

George Washington created the Blood Chit. It was used by his spies to identify themselves when returning to the continental Army. This one was used by American troops in Vietnam if separated from other crew members. You show this a local farmer. You hope he is not a Vietcong when he sees the American flag. It says: I am a citizen of the United States of America. I do not speak Your Language. Misfortune forces me to seek your assistance in obtaining food, shelter, and protection. Please take me to someone who will provide for my safety and see that I am returned to my people. My government will reward you.

This seems a bit formal for the farmer who probably can’t read or write.

I carried this Blood Chit in my wallet for a year.

Loosely interpreted as a written notice where blood may be spilled.

These are still used today.