31 dic 151 anni a. C. - Polybius Develops Alphabetical Smoke System
Descrizione:
In the year 150 BC, Greek historian Polybius develops alphabetical smoke signals sent out by holding pairs of torches. Smoke signals were used to transmit news, signal danger or gather people. It was commonly used in Ancient China and by North American Indigenous Tribes.Aggiunto al nastro di tempo:
Data:
31 dic 151 anni a. C.
Adesso
~ 2178 years ago