Almost anything that make a noise has been used for signaling. Cyrus,an ancient Persian ruler,established lines of signal towers. At each one, people with powerful vocies shouted a message to the next tower,and in this way, news and information was passed on through the kingdom. A kind of drum talk is still used a drum that can produce a high or low tone. Because the local dialect alternates in tones,the sender is able to simulate speech with the drums.