Chinese fire signals

During the Han Dynasty (206 B.C. – 220 A.D.), the Chinese used fire signals and smoke to transmit messages along the Great Wall and other strategic points. Different patterns of fire and smoke conveyed various types of information, similar to coded transmissions in amateur radio. This method highlighted the importance of visual signals in long-distance communication. Fire signals’ reliance on visibility and timing parallels the use of visual and timed codes in amateur radio, where clear, efficient communication is essential for successful message relay, especially in remote or challenging environments.