Smoke Signals
Native Americans used a type of communication called smoke signals. In this form of communication, puffs or columns of smoke were sent into the air in many different ways, signaling different things. The smoke signals were not exactly a full language, but were mostly used as brief signals of communication. Some of the recognized signals are remembered today. One puff of smoke sent into the air was believed to signal attention. Two puffs meant all's well or everything is okay. Three puffs signals either danger, call for help, or simply just trouble. The smoke is made by putting green branches or grass into the fire. Blankets are used to control the smoke puffs. Important events were also marked by smoke signals like war, death, or marriage. There were light and heavy signals, each meaning separate things. One meant good, the other meant bad. These smoke signals, the old form of Native American communication, are still used today by the military!
http://www.inquiry.net/OUTDOOR/native/sign/smoke-signal.htm
http://www.artipot.com/articles/206162/how-indians-used-smoke-as-communication.htm
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