This is another one of those divination methods which probably actually started with a bunch of Neanderthals in a cave, but the best I can tell you is it’s verifiably somewhere between three and five thousand years old. Author Eva Shaw said it was originally practiced by the ancient Babylonians, who used specifically cedar branches or cedar shavings as fuel for the smoke, and that they are said to have divined this way only on certain sacred days in the Babylonian calendar. The ancient Druids had a variation on this called dendromancy, for which they used both mistletoe and foliage cut from sacred oaks.

Author Charles Godfrey Leland stated that the ancient Etruscans had a variety of capnomancy in which sesame seeds and black poppy seeds were cast on hot coals and omens were drawn therefrom. If the seeds popped, then it was believed next year’s crop would be a good one. This form of capnomancy is actually something called causinomancy, which is the art of divining by observing how special objects either placed or thrown on the fire, burn. Causinomancy comes from the Greek word ‘kaustos’ which means ‘burned.’ As a general rule of thumb, if the special object cast into the fire burns rapidly, that is considered a favorable omen, and if it burns slowly, or it doesn’t burn at all, that is considered an unfavorable omen. If you throw a burnable item as directly as you can onto a fire or hot coals, but it somehow manages to bounce off something and lands smoldering on the periphery of the burning area, that implies a rejection of your efforts or desires, and it will not come to pass.