Ouroboros. The ouroboros or uroborus is an ancient symbol depicting a serpent or dragon eating its own tail. Originating in ancient Egyptian iconography, the ouroboros entered western tradition via Greek magical tradition and was adopted as a symbol in Gnosticism and Hermeticism and most notably in alchemy. The term derives from Ancient Greek:, from, tail +, food, from, I eat. The first known appearance of the ouroboros motif is in the Enigmatic Book of the Netherworld, an ancient Egyptian funerary text in KV62, the tomb of Tutankhamun, in the 14th century BC. The text concerns the actions of the god Ra and his union with Osiris in the underworld. The ouroboros is depicted twice on the figure: holding their tails in their mouths, one encircling the head and upper chest, the other surrounding the feet of a large figure, which may represent the unified Ra-Osiris. Both serpents are manifestations of the deity Mehen, who in other funerary texts protects Ra in his underworld journey. The whole divine figure represents the beginning and the end of time. The ouroboros appears elsewhere in Egyptian sources, where, like many Egyptian serpent deities, it represents the formless disorder that surrounds the orderly world and is involved in that world's periodic renewal. The symbol persisted in Egypt into Roman times, when it frequently appeared on magical talismans, sometimes in combination with other magical emblems. The 4th-century AD Latin commentator Servius was aware of the Egyptian use of the symbol, noting that the image of a snake biting its tail represents the cyclical nature of the year. The famous ouroboros drawing from the early alchemical text, The Chrysopoeia of Cleopatra, probably originally dating to third century Alexandria but first known in a tenth century copy, encloses the words hen to pan, the all is one. Its black and white halves may perhaps represent a Gnostic duality of existence, analogous to the Taoist yin and yang symbol. The chrysopoeia ouroboros of Cleopatra the Alchemist is one of the oldest images of the ouroboros to be linked with the legendary opus of the alchemists, the philosopher's stone. An aim of alchemists and adepts, described as individual self-perfection through physical transmutation and spiritual transcendence, was familiar to the alchemist and physician Sir Thomas Browne. It focused on the eternal unity of all things as well as the cycle of birth and death. In his A Letter to a Friend, a medical treatise full of case-histories and witty speculations upon the human condition, he wrote that the first day should make the last, that the Tail of the Snake should return into its Mouth precisely at that time, and they should wind up upon the day of their Nativity, is indeed a remarkable Coincidence. In Gnosticism, a serpent biting its tail symbolized eternity and the soul of the world. The Gnostic Pistis Sophia describes the ouroboros as a twelve-part dragon surrounding the world with its tail in its mouth. A 15th-century alchemical manuscript, The Aurora Consurgens, features the ouroboros, where it is used amongst symbols of the sun, moon, and mercury. In Norse mythology, the ouroboros appears as the serpent Jormungandr, one of the three children of Loki and Angrboda, which grew so large that it could encircle the world and grasp its tail in its teeth. In the legends of Ragnar Lodbrok, such as Ragnarssona pattr, the Geatish king Herraud gives a small lindworm as a gift to his daughter pora Town-Hart after which it grows into a large serpent which encircles the girl's bower and bites itself in the tail. The serpent is slain by Ragnar Lodbrok who marries pora. Ragnar later has a son with another woman named Kraka and this son is born with the image of a white snake in one eye. This snake encircled the iris and bit itself in the tail, and the son was named Sigurd Snake-in-the-Eye. It is a common belief among indigenous people of the tropical lowlands of South America that waters at the edge of the world-disc are encircled by a snake, often an anaconda, biting its own tail. In the Aitareya Brahmana, a Vedic text of the early 1st millennium BCE, the nature of the Vedic rituals is compared to a snake biting its own tail. Ouroboros symbolism has been used to describe the Kundalini.