Goetia

The circle and triangle, used in the evocation of the 72 spirits of the Goetia. The magickian would stand within the circle and the spirit was believed to appear within the triangle. Some believe that the central circle of the triangle was actually a magick mirror, similar to a crystal ball as used for scrying.

In occultism and demonology, Goetia (from the Greek 'goeteia' meaning witchcraft) is the art of invoking demons or other spirits and obliging them to do the conjurer's will, without falling under their power.

The Ars Goetia, first part of The Lesser Key of Solomon, is a good example of treatise on this subject, but it was already known and explained in earlier times, in the Key of Solomon and other mediaeval grimoires.

The book, "The Goetia - The Lesser Key of Solomon the King (Clavicula Salomonis Regis)" was translated by Samuel Liddell MacGregor Mathers, with an introduction by Aleister Crowley. It includes the Bornless Ritual, the seals of the spirits, their physical descriptions and actions. There are drawings done by Crowley for some of them.

Many of the so-called demons have their roots in earlier pagan Gods from the Sumerian and Mesopotamian pantheons, among others. There is also evidence that the texts were highly influenced by Islamic Alchemy, although the main structure is firmly rooted in Qabalah.