Aeromancy (from Greek ἀήρ aḗr, "air", and manteia, "divination") is divination conducted by interpreting atmospheric conditions. Alternate spellings include arologie, aeriology and aërology.
Aeromancy uses cloud formations, wind currents and cosmological events such as comets to attempt to divine the future. There are sub-types of this practice which are as follows:
- Austromancy (wind divination)
- Ceraunoscopy (observing thunder and lightning)
- Chaomancy (aerial vision)
- Meteormancy (meteors and shooting stars)
- Nephomancy (cloud divination)
The first recorded instance of the word aeromancy being used was found in Chambers, Cycl. Supp, 1753. It was defined as "That department of science which treats of the atmosphere", rather than a form of divination. However, variations on the word have been used throughout history with the earliest instance being in the Bible, though the practice is thought to have been used by the ancient Babylonian priests.
Damascius, the last of the Neoplatonists, records an account of nephomancy in the 5th century CE, during the reign of Leo I:
Wherefore one finds a woman in the days of Leo the Roman emperor who knew neither by sense of hearing nor by the ancient practices the art of divination by clouds. The woman came from Aigai in Cilicia, having come from the family of the Orestiadai who dwell on the mountain at Komana in Cappadocia. Her family went back to the Peloponnese. She took thought for a man entrusted with a military command who was sent with others to the war against the Vandals in Sicily. She prayed to foresee the future by dream and prayed facing the rising sun. Her father prescribed and commanded her in a dream to pray toward the west. When she prayed, a cloud from the upper air stood around the sun, and became enlarged and took the shape of a man. Another cloud sheared off and rendered itself of equal size and took the shape of a wild lion. It went into a great rage and, having made a great chasm, the lion swallowed the man. The human, cloud-made shape was like a Goth. A little more about the apparitions; Thereupon the emperor Leo slew Aspar himself, the hegemon of the Goths (in Constantinople) and his children. From that time Anthusa has continued until now without interruption to practice the custom of mantic prediction through clouds.
Aeromancy was mentioned in Deuteronomy 18 as being condemned by Moses. It is also condemned by Albertus Magnus in Speculum Astronomiae, who describes the practice as a derivative of necromancy. The practice was debunked by Luis de Valladolid in his 1889 work Historia de vita et doctrina Alberti Magni.