Smoke signals were used by Native American tribes as a way of sending simple messages over long distances. They weren’t the only people to do so: the system was used in Ancient China and Ancient Greece, and by the Australian Aboriginals; it’s even used today in the Vatican to indicate, by the colour of the smoke, whether or not the Cardinals have been successful in electing a new Pope.
Smoke signals were used between the members of tribes and were pre-arranged to have set meanings. If there were enemies about, the code might have to be less straightforward so that it would remain private. But at its simplest the most usual code was: one puff meaning ‘Attention’, two puffs meaning ‘All is well’, and three puffs meaning that the sender of the signal was in danger of some kind – this last now being a standard distress signal for Boy Scouts, etc. Anything more complex was usually specific to the occasion.
A fire was built – usually on top of a conical mound – using damp grass and animal dung so that it produced smoke. The position of the fire itself might have a meaning – at the top of the mound it would indicate danger, while half way down the mound it was a reassuring communication. The signal itself was made by smothering the smoke under a blanket or animal hide, then releasing it in concentrated bursts. Further information could be conveyed by secondary fires. If a battle had been won, this might be conveyed by the main fire, then smaller fires might release puffs of smoke that indicated the numbers of scalps or horses taken in that battle.
Native American tribesmen could be very inventive in the way they fashioned the smoke in the signal. For example the Karankawa tribe of South Texas had twenty different kinds of signal which included spirals, zigzags and diverging lines as well as the standard columns. The colour of the smoke could be controlled by changing from drier material which produced white smoke to damper material and even oil which produced dark smoke.
If signals needed to be sent over a long distance, a chain of fires would be lit and each station would signal to the next in a relay. Smoke signals were used in the day, and fires by night – using a clearer line of sight, perhaps.
When out hunting, or in situations where there was no time to build a fire, Native Americans used mirrors made of mica or glass to send flashes of light and convey information according to a prearranged code, exactly like with smoke signals. They also sometimes stood on high ground where they were clearly visible and used the gestures and postures of their bodies to create shapes that had meaning. This is obviously akin to semaphore.
There were more extreme methods of communication, too. Certain Native Americans had the habit of setting the prairie on fire to tell the local tribes that they’d arrived and wished to parley. It was hardly the most diplomatic approach, but perfect if the intention was to be confrontational.