Spies
Information passing in the First World War was made possible by pigeon post. Doing the job of spying by delivering letters up to 90 miles away was best done by tying them up on pigeon backs and releasing them home. At a time when enemy forces discovered the trick and were shooting them down, users of the 'pigeon post,' as it was known, painted them black so they would be confused for crows. Initially, they would only travel home (one way) but later on, their food was stationed away from home so they learned to travel to and fro ...