Walter Kellogg Towers

I COMMUNICATION AMONG THE ANCIENTS     Signaling the Fall of Troy—Marine Signaling among the    Argonauts—Couriers of the Greeks, Romans, and    Aztecs—Sound-signaling—Stentorophonic Tube—The Shouting    Sentinels—The Clepsydra—Signal Columns—Indian Fire and Smoke    Signals. It was very early in the history of the world that man began to feel the urgent need of... more...