Ceneromancy (also known as cineromancy, spodomancy, tephramancy , tephromancy, libanomancy, xylomancy) is an ancient and globally widespread divination practice. The ancient Greek playwright Aeschylus (525 BC–456 BC) noted that ashes falling from a fireplace could be divined for portents. A word, phrase, name, or question would be written in the ashes with a finger or stick. The individual would wait for a breeze to disturb the ashes, which would form new letters or omens and provide an answer. Not everyone could practice the art. The gift of prophecy was believed to run in some Greek families, and only they were allowed to seek divination from the ashes left by fires on sacrificial altars. In Ancient Thebes, the altar dedicated to Apollo was known as "Apollo of the Ashes" not only because the altar itself was composed of the ashes of human sacrificial victims but because ashes blowing off the altar could be divined for their portents. The Etruscans of the Italian peninsula, whose civilization existed from 1200 BC to 550 BC, also practiced ceneromancy in a fashion similar to the Greeks. Romani (Gypsy) folklore says ashes can be cast onto the floor. Smooth, uniform ashes are a good omen, while a pile (or piles) of ashes indicate bad fortune. During the Qin (221 BC–206 BC) and Han (206 BCE–220 CE) dynasties in China, a form of ceneromancy was used in which the bones of sacrificial animals were raked out of fires and the marks in the ashes and cracks in the bones interpreted for their portents. Several Native American tribes believed that they could divine the future of a newborn or a friend who had left on a journey by looking in the marks and lines left in the ashes of a fire the next morning. From the 16th century to mid 19th century, unmarried English people would draw lines in smooth ashes. The ashes were an indication of a future spouse if two unmarried people sat on the same line. In Kent, this custom was used on Valentine's Day to divine who one should court. Peruvians in the late 19th century would spread ashes on the floor the night after a funeral. The next morning, footprints and other marks in the ashes would indicate what kind of animal the dead person's soul had migrated into and the direction in which that animal might be found. Among the Loma people of western Africa, ceneromancy is still (as of the late 20th century) used to divine the sex of a child before birth. Chinese people in Taiwan still use the ends of sedan chair poles to mark incense ash on altars, and then interpret the marks for divine communication.
The Greco-Etruscan form of the practice seems to be the most common in Europe, historically. But the rites of the practice varied widely even into the early Renaissance. In The Works of Rabelais, Book III (published in 1693), Sir Thomas Urquhart claimed that the ashes and soot must be allowed to rise naturally from the fire. The ashes were interpreted as they rose. Ashes which dispersed quickly were a positive sign, but ashes which hung in the air were not. Another tradition indicates that spodomancy may also be practiced by writing a question or message on a piece of paper and then burning it. The burned ashes and soot of the burned message were then examined for omens and interpretation. In Slavonia, only women were permitted to practice ceneromancy. A woman would scratch in the ashes. An even number of scratches meant a positive outcome, while an odd number meant bad luck. In Poland, too, only women could practice the art. Ashes would be spread around the bed of a sick person, and the signs which appeared in the ashes were interpreted to indicate whether the person would become healthy again or not. The practice of ceneromancy continues to evolve even today. For example, modern Wiccans argue that the fire used by the ceneromancer must be a sacred one.
Some ceneromantic rituals require the use of a certain writing surface. Most of the rituals outlined above indicate the use of the hearth, floor, or exterior ground as the place to spread ashes. But some examples of ceneromancy call for the use of other types of surfaces. Consider the use of bone: Divination techniques closely related to ceneromancy include osteomancy (divination using bones, particularly that practice which heats them to produce cracks which are portentious), plastromancy (divination using turtle plastrons), scapulimancy (divination using the shoulder blade; the Scottish term is slinneanachd), and sternomancy (divination using the sternum). However, in these practices, fire is used to cause cracks to appear in the bone. Ash may or may not be used to fill in these cracks, making them more visible. This is not ceneromancy, however, as the cracks (not the ash itself) are being read. In Mongolia, however, a divinatory ritual exists in which scapulimancy and ceneromancy are combined: A smooth layer of ashes is spread on the shoulder blade of a cow, sheep, or ox, and a lama is divinely inspired to make calculations in the ash which indicate answers to questions or the future. Bone is not the only alternative surface used. Some ancient Greek rituals of ceneromancy required that the ashes be spread on a plank of wood rather than the floor.
In the Celtic pagan tradition, ceneromancy did not necessarily require the reading of ashes themselves. The filidh were a class of poet-judge-seers who functioned as keepers of mythology and knowledge, historians, lawyers, arbitrators, linguistic experts, and more. One branch of the filidh was expert solely in divination and dreams, and it was commonly believed that simply sleeping next to the ashes of an animal burned in a sacrificial fire could lead to knowledge about the future.
Historical and modern writers consider ceneromancy one of the least-familiar methods of divination. Nonetheless, it was common enough in Spain in the late 16th century so that Archbishop of Seville and Grand Inquisitor Alonso Manrique de Lara had to openly ban the practice. It also seems to have been widely practiced in northwestern Germany around the same time.
en.wikipedia.org/wiki/Spodomancy
occult-world.com/cineromancy-divinations/ 
