Ancient Discoveries S06E04 - Ancient Secret Agents

The systems by which ancient intelligence services transmitted messages over thousands of miles is investigated. Methods by which ancient spies sent secret messages are reviewed such as invisible ink made of human sperm and how they wrote on the inside of a raw egg. Discover how the ninja used explosives, not just darts and poisons. How a Roman James Bond used a suit made of cork to support him in full armor across a river is also explored.